The present invention relates generally to the field of robotic medical procedure systems and, in particular, to apparatus and methods for robotically controlling the movement and operation of elongated medical devices.
Catheters and other elongated medical devices (EMDs) may be used for minimally invasive medical procedures for the diagnosis and treatment of diseases of various vascular systems, including neurovascular intervention (NVI) also known as neurointerventional surgery, percutaneous coronary intervention (PCI) and peripheral vascular intervention (PVI). These procedures typically involve navigating a guidewire through the vasculature, and via the guidewire advancing a catheter to deliver therapy. The catheterization procedure starts by gaining access into the appropriate vessel, such as an artery or vein, with an introducer sheath using standard percutaneous techniques. Through the introducer sheath, a sheath or guide catheter is then advanced over a diagnostic guidewire to a primary location such as an internal carotid artery for NVI, a coronary ostium for PCI, or a superficial femoral artery for PVI. A guidewire suitable for the vasculature is then navigated through the sheath or guide catheter to a target location in the vasculature. In certain situations, such as in tortuous anatomy, a support catheter or microcatheter is inserted over the guidewire to assist in navigating the guidewire. The physician or operator may use an imaging system (e.g., fluoroscope) to obtain a cine with a contrast injection and select a fixed frame for use as a roadmap to navigate the guidewire or catheter to the target location, for example, a lesion. Contrast-enhanced images are also obtained while the physician delivers the guidewire or catheter so that the physician can verify that the device is moving along the correct path to the target location. While observing the anatomy using fluoroscopy, the physician manipulates the proximal end of the guidewire or catheter to direct the distal tip into the appropriate vessels toward the lesion or target anatomical location and avoid advancing into side branches.
Robotic catheter-based procedure systems have been developed that may be used to aid a physician in performing catheterization procedures such as, for example, NVI, PCI and PVI. Examples of NVI procedures include coil embolization of aneurysms, liquid embolization of arteriovenous malformations and mechanical thrombectomy of large vessel occlusions in the setting of acute ischemic stroke. In an NVI procedure, the physician uses a robotic system to gain target lesion access by controlling the manipulation of a neurovascular guidewire and microcatheter to deliver the therapy to restore normal blood flow. Target access is enabled by the sheath or guide catheter but may also require an intermediate catheter for more distal territory or to provide adequate support for the microcatheter and guidewire. The distal tip of a guidewire is navigated into, or past, the lesion depending on the type of lesion and treatment. For treating aneurysms, the microcatheter is advanced into the lesion and the guidewire is removed and several embolization coils are deployed into the aneurysm through the microcatheter and used to block blood flow into the aneurysm. For treating arteriovenous malformations, a liquid embolic is injected into the malformation via a microcatheter. Mechanical thrombectomy to treat vessel occlusions can be achieved either through aspiration and/or use of a stent retriever. Depending on the location of the clot, aspiration is either done through an aspiration catheter, or through a microcatheter for smaller arteries. Once the aspiration catheter is at the lesion, negative pressure is applied to remove the clot through the catheter. Alternatively, the clot can be removed by deploying a stent retriever through the microcatheter. Once the clot has integrated into the stent retriever, the clot is retrieved by retracting the stent retriever and microcatheter (or intermediate catheter) into the guide catheter.
In PCI, the physician uses a robotic system to gain lesion access by manipulating a coronary guidewire to deliver the therapy and restore normal blood flow. The access is enabled by seating a guide catheter in a coronary ostium. The distal tip of the guidewire is navigated past the lesion and, for complex anatomies, a microcatheter may be used to provide adequate support for the guidewire. The blood flow is restored by delivering and deploying a stent or balloon at the lesion. The lesion may need preparation prior to stenting, by either delivering a balloon for pre-dilation of the lesion, or by performing atherectomy using, for example, a laser or rotational atherectomy catheter and a balloon over the guidewire. Diagnostic imaging and physiological measurements may be performed to determine appropriate therapy by using imaging catheters or fractional flow reserve (FFR) measurements.
In PVI, the physician uses a robotic system to deliver the therapy and restore blood flow with techniques similar to NVI. The distal tip of the guidewire is navigated past the lesion and a microcatheter may be used to provide adequate support for the guidewire for complex anatomies. The blood flow is restored by delivering and deploying a stent or balloon to the lesion. As with PCI, lesion preparation and diagnostic imaging may be used as well.
When support at the distal end of a catheter or guidewire is needed, for example, to navigate tortuous or calcified vasculature, to reach distal anatomical locations, or to cross hard lesions, an over-the-wire (OTW) catheter or coaxial system is used. An OTW catheter has a lumen for the guidewire that extends the full length of the catheter. This provides a relatively stable system because the guidewire is supported along the whole length. This system, however, has some disadvantages, including higher friction, and longer overall length compared to rapid-exchange catheters (see below). Typically to remove or exchange an OTW catheter while maintaining the position of the indwelling guidewire, the exposed length (outside of the patient) of guidewire must be longer than the OTW catheter. A 300 cm long guidewire is typically sufficient for this purpose and is often referred to as an exchange length guidewire. Due to the length of the guidewire, two operators are needed to remove or exchange an OTW catheter. This becomes even more challenging if a triple coaxial, known in the art as a tri-axial system, is used (quadruple coaxial catheters have also been known to be used). However, due to its stability, an OTW system is often used in NVI and PVI procedures. On the other hand, PCI procedures often use rapid exchange (or monorail) catheters. The guidewire lumen in a rapid exchange catheter runs only through a distal section of the catheter, called the monorail or rapid exchange (RX) section. With a RX system, the operator manipulates the interventional devices parallel to each other (as opposed to with an OTW system, in which the devices are manipulated in a serial configuration), and the exposed length of guidewire only needs to be slightly longer than the RX section of the catheter. A rapid exchange length guidewire is typically 180-200 cm long. Given the shorter length guidewire and monorail, RX catheters can be exchanged by a single operator. However, RX catheters are often inadequate when more distal support is needed.
An EMD drive system includes an on-device adapter removably fixed to a shaft of an EMD. The on-device adapter received in a cassette. The cassette is removably secured to a drive module. The drive module is operatively coupled to the on-device adapter to move the on-device adapter and EMD together.
In one embodiment an EMD drive system includes a collet removably fixed to an EMD. The EMD, fixed to the collet, is radially loaded into a robotic drive. An EMD support is removably applied to the EMD from a non-axial direction; and the robotic drive is operatively coupled to the collet to translate and/or rotate the collet and EMD
In one embodiment a robotic system includes a robotic drive including a base having a drive coupler. A cassette is removably secured to the base. A collet in the cassette is removably fixed to an EMD. The collet has a driven member being operatively coupled to the drive coupler; and the robotic drive includes a motor operatively coupled to the collet to move the collet
In one embodiment a robotic system includes a collet having a first portion having a first collet coupler connected thereto and a second portion having a second collet coupler connected thereto. An EMD is removably located within a pathway defined by the collet. A robotic drive including a base having a first motor and a second motor operatively continuously coupled to both the first collet coupler and the second collet coupler respectively to operatively pinch and unpinch the EMD in the pathway and to rotate the EMD.
In one embodiment a collet includes an inner member defining a pathway receiving an EMD and an outer member. A plurality of engagement members releasably engage the EMD as the inner member is moved relative to the outer member.
In one embodiment an EMD drive system includes a collet having a collet first member having a first engagement portion. The collet has a second member that is driven. A collet engagement member has a second engagement portion. The collet first member and the collet engagement member move between an engaged position and a disengaged position. The first engagement portion engages the second engagement portion as the collet first member and collet engagement member are moved to the engaged position. Rotation of the collet first member with respect to the collet second member in a first direction in the engaged position pinches an EMD within the collet and rotation of the collet first member with respect to the collect second member in a second direction opposite the first direction unpinches the EMD within the collet.
In another embodiment an EMD robotic drive system rotating and translating an EMD with reset instructions, includes a drive module controlled by a control system, the drive module including; a first actuator operatively rotating a first shaft and/or a second shaft; a second actuator operatively translating the first shaft along its longitudinal axis relative to the second shaft from a first position to a second position; a first tire assembly operatively attached to the first shaft; a second tire assembly operatively attached to a second shaft; a third actuator operatively moving the first tire assembly toward and away from the second tire assembly gripping and ungripping an EMD having a longitudinal axis from between the first tire assembly and the second tire assembly. The translation of the first shaft relative to the second shaft rotates the EMD about the longitudinal axis of the EMD, and rotation of the first shaft and/or second shaft translates the EMD along the longitudinal axis of the EMD. A control system provides reset instructions to the third actuator to ungrip the EMD; the second actuator to move the first tire assembly relative to the second tire assembly to a reset position; and the third actuator to grip the EMD.
In still another embodiment an EMD robotic drive system comprising a drive module including a first actuator operatively rotating a first shaft and/or a second shaft; a second actuator operatively translating the first shaft along its longitudinal axis relative to the second shaft from a first position to a second position; a first tire assembly removably attached to the first shaft; a second tire assembly removably attached to a second shaft. An EMD having a longitudinal axis is positioned at a first location between the first tire assembly and the second tire assembly. Rotation of the first shaft translates an EMD along its longitudinal axis between the first tire assembly and the second tire assembly; and rotation of the second shaft rotates the EMD about its longitudinal axis. A third actuator operatively moves the first tire assembly toward and away from the second tire assembly gripping and ungripping the EMD from between the first tire assembly and the second tire assembly. A holding clamp releasably clamps a portion of the EMD spaced from the first tire and the second tire along the longitudinal axis of the EMD.
In one embodiment an EMD robotic drive system includes a first actuator operatively rotating a first shaft and/or a second shaft. A second actuator operatively translates the first shaft along its longitudinal axis relative to the second shaft from a first position to a second position. A first tire assembly is operatively attached to the first shaft. A second tire assembly is operatively attached to a second shaft. A third actuator operatively moves the first tire assembly toward and away from the second tire assembly gripping and ungripping an EMD having a longitudinal axis from between the first tire assembly and the second tire assembly. Translation of the first shaft relative to the second shaft rotates the EMD about the longitudinal axis of the EMD, and rotation of the first shaft and/or second shaft translates the EMD along the longitudinal axis of the EMD. The first actuator moves with the first shaft as the first shaft is moved along its longitudinal axis away from a home position.
In one embodiment a method of robotically moving an EMD includes pinching a shaft of an EMD in an on-device adapter. Removably securing the on-device adapter into a cassette. Removably securing the cassette to a drive module; and robotically moving the on-device adapter and the EMD together in translation along a longitudinal axis of the EMD and/or rotation about the longitudinal axis of the EMD. In a further aspect the method includes unpinching the EMD in the on-device adapter with an actuator when the on-device adapter is secured in the cassette. In a further aspect the method includes unpinching the EMD is robotically controlled with an actuator.
Catheter-based procedure system 10 includes, among other elements, a bedside unit 20 and a control station 26. Bedside unit 20 includes a robotic drive 24 and a positioning system 22 that are located adjacent to a patient 12. Patient 12 is supported on a patient table 18. The positioning system 22 is used to position and support the robotic drive 24. The positioning system 22 may be, for example, a robotic arm, an articulated arm, a holder, etc. The positioning system 22 may be attached at one end to, for example, a rail on the patient table 18, a base, or a cart. The other end of the positioning system 22 is attached to the robotic drive 24. The positioning system 22 may be moved out of the way (along with the robotic drive 24) to allow for the patient 12 to be placed on the patient table 18. Once the patient 12 is positioned on the patient table 18, the positioning system 22 may be used to situate or position the robotic drive 24 relative to the patient 12 for the procedure. In an embodiment, patient table 18 is operably supported by a pedestal 17, which is secured to the floor and/or earth. Patient table 18 is able to move with multiple degrees of freedom, for example, roll, pitch, and yaw, relative to the pedestal 17. Bedside unit 20 may also include controls and displays 46 (shown in
Generally, the robotic drive 24 may be equipped with the appropriate percutaneous interventional devices and accessories 48 (shown in
Bedside unit 20 is in communication with control station 26, allowing signals generated by the user inputs of control station 26 to be transmitted wirelessly or via hardwire to bedside unit 20 to control various functions of bedside unit 20. As discussed below, control station 26 may include a control computing system 34 (shown in
Control station 26 generally includes one or more input modules 28 configured to receive user inputs to operate various components or systems of catheter-based procedure system 10. In the embodiment shown, control station 26 allows the user or operator 11 to control bedside unit 20 to perform a catheter-based medical procedure. For example, input modules 28 may be configured to cause bedside unit 20 to perform various tasks using percutaneous intervention devices (e.g., EMDs) interfaced with the robotic drive 24 (e.g., to advance, retract, or rotate a guidewire, advance, retract or rotate a catheter, inflate or deflate a balloon located on a catheter, position and/or deploy a stent, position and/or deploy a stent retriever, position and/or deploy a coil, inject contrast media into a catheter, inject liquid embolics into a catheter, inject medicine or saline into a catheter, aspirate on a catheter, or to perform any other function that may be performed as part of a catheter-based medical procedure). Robotic drive 24 includes various drive mechanisms to cause movement (e.g., axial and rotational movement) of the components of the bedside unit 20 including the percutaneous intervention devices.
In one embodiment, input modules 28 may include one or more touch screens, joysticks, scroll wheels, and/or buttons. In addition to input modules 28, the control station 26 may use additional user controls 44 (shown in
Control station 26 may include a display 30. In other embodiments, the control station 26 may include two or more displays 30. Display 30 may be configured to display information or patient specific data to the user or operator 11 located at control station 26. For example, display 30 may be configured to display image data (e.g., X-ray images, MRI images, CT images, ultrasound images, etc.), hemodynamic data (e.g., blood pressure, heart rate, etc.), patient record information (e.g., medical history, age, weight, etc.), lesion or treatment assessment data (e.g., IVUS, OCT, FFR, etc.). In addition, display 30 may be configured to display procedure specific information (e.g., procedural checklist, recommendations, duration of procedure, catheter or guidewire position, volume of medicine or contrast agent delivered, etc.). Further, display 30 may be configured to display information to provide the functionalities associated with control computing system 34 (shown in
Catheter-based procedure system 10 also includes an imaging system 14. Imaging system 14 may be any medical imaging system that may be used in conjunction with a catheter based medical procedure (e.g., non-digital X-ray, digital X-ray, CT, MRI, ultrasound, etc.). In an exemplary embodiment, imaging system 14 is a digital X-ray imaging device that is in communication with control station 26. In one embodiment, imaging system 14 may include a C-arm (shown in
Imaging system 14 may be configured to take X-ray images of the appropriate area of patient 12 during a procedure. For example, imaging system 14 may be configured to take one or more X-ray images of the head to diagnose a neurovascular condition. Imaging system 14 may also be configured to take one or more X-ray images (e.g., real time images) during a catheter-based medical procedure to assist the user or operator 11 of control station 26 to properly position a guidewire, guide catheter, microcatheter, stent retriever, coil, stent, balloon, etc. during the procedure. The image or images may be displayed on display 30. For example, images may be displayed on display 30 to allow the user or operator 11 to accurately move a guide catheter or guidewire into the proper position.
In order to clarify directions, a rectangular coordinate system is introduced with X, Y, and Z axes. The positive X axis is oriented in a longitudinal (axial) distal direction, that is, in the direction from the proximal end to the distal end, stated another way from the proximal to distal direction. The Y and Z axes are in a transverse plane to the X axis, with the positive Z axis oriented up, that is, in the direction opposite of gravity, and the Y axis is automatically determined by right-hand rule.
In various embodiments, control computing system 34 is configured to generate control signals based on the user's interaction with input modules 28 (e.g., of a control station 26 (shown in
Catheter-based procedure system 10 may be connected or configured to include any other systems and/or devices not explicitly shown. For example, catheter-based procedure system 10 may include image processing engines, data storage and archive systems, automatic balloon and/or stent inflation systems, medicine injection systems, medicine tracking and/or logging systems, user logs, encryption systems, systems to restrict access or use of catheter-based procedure system 10, etc.
As mentioned, control computing system 34 is in communication with bedside unit 20 which includes a robotic drive 24, a positioning system 22 and may include additional controls and displays 46, and may provide control signals to the bedside unit 20 to control the operation of the motors and drive mechanisms used to drive the percutaneous intervention devices (e.g., guidewire, catheter, etc.). The various drive mechanisms may be provided as part of a robotic drive 24.
Each device module 32a-d includes a drive module 68a-d and a cassette 66a-d mounted on and coupled to the drive module 68a-d. In the embodiment shown in
To prevent contaminating the patient with pathogens, healthcare staff use aseptic technique in a room housing the bedside unit 20 and the patient 12 or subject (shown in
Distal and Proximal: The terms distal and proximal define relative locations of two different features. With respect to a robotic drive the terms distal and proximal are defined by the position of the robotic drive in its intended use relative to a patient. When used to define a relative position, the distal feature is the feature of the robotic drive that is closer to the patient than a proximal feature when the robotic drive is in its intended in-use position. Within a patient, any vasculature landmark further away along the path from the access point is considered more distal than a landmark closer to the access point, where the access point is the point at which the EMD enters the patient. Similarly, the proximal feature is the feature that is farther from the patient than the distal feature when the robotic drive in its intended in-use position. When used to define direction, the distal direction refers to a path on which something is moving or is aimed to move or along which something is pointing or facing from a proximal feature toward a distal feature and/or patient when the robotic drive is in its intended in-use position. The proximal direction is the opposite direction of the distal direction. By way of examples referring to
Longitudinal axis: The term longitudinal axis of a member (for example, an EMD or other element in the catheter-based procedure system) is the line or axis along the length of the member that passes through the center of the transverse cross section of the member in the direction from a proximal portion of the member to a distal portion of the member. For example, the longitudinal axis of a guidewire is the central axis in the direction from a proximal portion of the guidewire toward a distal portion of the guidewire even though the guidewire may be non-linear in the relevant portion.
Axial Movement: The term axial movement of a member refers to translation of the member along the longitudinal axis of the member. When the distal end of an EMD is axially moved in a distal direction along its longitudinal axis into or further into the patient, the EMD is being advanced. When the distal end of an EMD is axially moved in a proximal direction along its longitudinal axis out of or further out of the patient, the EMD is being withdrawn.
Rotational Movement: The term rotational movement of a member refers to the change in angular orientation of the member about the local longitudinal axis of the member. Rotational movement of an EMD corresponds to clockwise or counterclockwise rotation of the EMD about its longitudinal axis due to an applied torque.
Axial and Lateral Insertion: The term axial insertion refers to inserting a first member into a second member along the longitudinal axis of the second member. An EMD that is axially loaded in a collet is axially inserted in the collet. An example of axial insertion could be referred to as back loading a catheter on the proximal end of a guidewire. The term lateral insertion refers to inserting a first member into a second member along a direction in a plane perpendicular to the longitudinal axis of the second member. This can also be referred to as radial loading or side loading. Stated another way, lateral insertion refers to inserting a first member into a second member along a direction that is parallel to the radius and perpendicular to the longitudinal axis of the second member.
Pinch/Unpinch: The term pinch refers to releasably fixing an EMD to a member such that the EMD and member move together when the member moves. The term unpinch refers to releasing the EMD from a member such that the EMD and member move independently when the member moves.
Clamp/Unclamp: The term clamp refers to releasably fixing an EMD to a member such that the EMD's movement is constrained with respect to the member. The member can be fixed with respect to a global coordinate system or with respect to a local coordinate system. The term unclamp refers to releasing the EMD from the member such that the EMD can move independently.
Grip/Ungrip: The term grip refers to the application of a force or torque to an EMD by a drive mechanism that causes motion of the EMD without slip in at least one degree of freedom. The term ungrip refers to the release of the application of the force or torque to the EMD by a drive mechanism such that the position of the EMD is no longer constrained. In one example an EMD is gripped between two tires rotates about its longitudinal axis when the tires move longitudinally relative to one another. The rotational movement of the EMD is different than the movement of the two tires. The position of an EMD that is gripped is constrained by the drive mechanism.
Buckling: The term buckling refers to the tendency of a flexible EMD when under axial compression to bend away from the longitudinal axis or intended path along which it is being advanced. In one embodiment axial compression occurs in response to resistance from being navigated in the vasculature. The distance an EMD may be driven along its longitudinal axis without support before the EMD buckles is referred to herein as the device buckling distance. The device buckling distance is a function of the device's stiffness, geometry (including but not limited to diameter), and force being applied to the EMD. Buckling may cause the EMD to form an arcuate portion different than the intended path. Kinking is a case of buckling in which deformation of the EMD is non-elastic resulting in a permanent set.
Homing: The term homing refers to moving a member to a defined position. An example of a defined position is a reference position. Another example of a defined position is an initial position. The term home refers to the defined position. It is normally used as a reference for subsequent linear or rotational positions.
Up/Down; Front/Rear; Inwardly/Outwardly: The terms top, up, and upper refer to the general direction away from the direction of gravity and the terms bottom, down, and lower refer to the general direction in the direction of gravity. The term front refers to the side of the robotic drive that faces a bedside user and away from the positioning system, such as the articulating arm. The term rear refers to the side of the robotic drive that is closest to the positioning system, such as the articulating arm. The term inwardly refers to the inner portion of a feature. The term outwardly refers to the outer portion of a feature.
Stage: The term stage refers to a member, feature, or device that is used to couple a device module to the robotic drive. For example, the stage may be used to couple the device module to a rail or linear member of the robotic drive.
Drive Module: The term drive module generally refers to the part (e.g., the capital part) of the robotic drive system that normally contains one or more motors with drive couplers that interface with the cassette.
Device Module: The term device module refers to the combination of a drive module and a cassette.
Cassette The term cassette generally refers to the part (non-capital, consumable or sterilizable unit) of the robotic drive system that normally is the sterile interface between a drive module and at least one EMD (directly) or through a device adapter (indirectly).
Collet: The term collet refers to a device that can releasably fix a portion of an EMD. The term fixed here means no intentional relative movement of the collet and EMD during operation. In one embodiment the collet includes at least two members that move rotationally relative to each other to releasably fix the EMD to at least one of the two members. In one embodiment the collet includes at least two members that move axially (along a longitudinal axis) relative to each other to releasably fix the EMD to at least one of the two members. In one embodiment the collet includes at least two members that move rotationally and axially relative to each other to releasably fix the EMD to at least one of the two members.
Fixed: The term fixed means no intentional relative movement of a first member with respect to a second member during operation.
On-Device Adapter: The term on-device adapter refers to a sterile apparatus capable of releasably pinching an EMD to provide a driving interface. The on-device adapter is also known as an end-effector or EMD capturing device. In one non-limiting embodiment the on-device adapter is a collet that is operatively controlled robotically to rotate the EMD about its longitudinal axis, to pinch and/or unpinch the EMD to the collet, and/or to translate the EMD along its longitudinal axis. In one embodiment the on-device adapter is a hub-drive mechanism such as a driven gear located on the hub of an EMD.
Tandem Drive: The term tandem drive refers to a drive unit or subsystem within the robotic drive containing two or more EMD drive modules, capable of manipulating one or more EMDs.
EMD: The term elongated medical device (EMD) refers to, but is not limited to, catheters (e.g., guide catheters, microcatheters, balloon/stent catheters), wire-based devices (e.g., guidewires, embolization coils, stent retrievers, etc.), and medical devices comprising any combination of these. In one example a wire-based EMD includes but is not limited to guidewires, microwires, a proximal pusher for embolization coils, stent retrievers, self-expanding stents, and flow divertors. Typically wire-based EMD's do not have a hub or handle at its proximal terminal end. In one embodiment the EMD is a catheter having a hub at a proximal end of the catheter and a flexible shaft extending from the hub toward the distal end of the catheter, wherein the shaft is more flexible than the hub. In one embodiment the catheter includes an intermediary portion that transitions between the hub and the shaft that has an intermediate flexibility that is less rigid than the hub and more rigid than the shaft. In one embodiment the intermediary portion is a strain relief.
Hub (Proximal) Driving: The term hub driving or proximal driving refers to holding on to and manipulating an EMD from a proximal position (e.g., a geared adapter on a catheter hub). In one embodiment, hub driving refers to imparting a force or torque to the hub of a catheter to translate and/or rotate the catheter. Hub driving may cause the EMD to buckle and thus hub driving often requires anti-buckling features. For devices that do not have hubs or other interfaces (e.g., a guidewire), device adapters may be added to the device to act as an interface for the device module. In one embodiment, an EMD does not include any mechanism to manipulate features within the catheter such as wires that extend from the handle to the distal end of the catheter to deflect the distal end of the catheter.
Shaft (Distal) Driving: The term shaft (distal) driving refers to holding on to and manipulating an EMD along its shaft. In one example the on-device adapter is normally placed just proximal of the hub or Y-connector the device is inserted into. If the location of the on-device adapter is at the proximity of an insertion point (to the body or another catheter or valve), shaft driving does not typically require anti-buckling features. (It may include anti-buckling features to improve drive capability.)
Sterilizable Unit: The term sterilizable unit refers to an apparatus that is capable of being sterilized (free from pathogenic microorganisms). This includes, but is not limited to, a cassette, consumable unit, drape, device adapter, and sterilizable drive modules/units (which may include electromechanical components). Sterilizable Units may come into contact with the patient, other sterile devices, or anything else placed within the sterile field of a medical procedure.
Sterile Interface: The term sterile interface refers to an interface or boundary between a sterile and non-sterile unit. For example, a cassette may be a sterile interface between the robotic drive and at least one EMD.
Reset The term reset means repositioning a drive mechanism from a first position to a second position to allow for continued rotational and/or axial movement of an EMD. During reset, the EMD is not actively being moved by the drive mechanism. In one embodiment the EMD is released by the drive mechanism prior to repositioning the drive mechanism. In one embodiment a clamp fixes the location of the EMD during repositioning of the drive mechanism.
Continuous Motion: The term continuous motion refers to motion that does not require a reset and is uninterrupted.
Discrete Motion: The term discrete motion refers to motion that requires a reset and is interrupted.
Consumable: The term consumable refers to a sterilizable unit that normally has a single use in a medical procedure. The unit could be a reusable consumable through a re-sterilization process for use in another medical procedure.
Device Support: The term device support refers to a member, feature, or device that prevents an EMD from buckling.
Double Gear: The term double-gear refers to two independently driven gears operatively connected to two different portions of a device. Each of the two gears may be identical or different design. The term gear may be a bevel gear, spiral bevel gear, spur gear, miter gear, worm gear, helical gear, rack and pinon, screw gear, internal gear such as a sun gear, involute spline shafts and bushing, or any other type of gears known in the art. In one example, double-gear also includes devices in which any drive connection is maintained by two different portions of a device, including but not limited to a belt, friction engagement or other couplers known in the art.
Referring to
In one embodiment the collet 112 includes at least two members that move relative to each other to releasably fix the shaft portion of the EMD to at least one of the two members. In one embodiment the two members operating together provide a mechanical advantage that increases the torque and/or force that may be transmitted from the collet body to the shaft of the EMD without the shaft of the EMD moving relative to the collet body. The pinch force on the EMD using a collet can be greater than the force required to actuate the pinch. When the shaft of the EMD is pinched it is fixed such that there is relative movement of the collet and EMD during acceptable operation parameters of an EMD procedure.
EMD 102 is fixed to the collet 112 and radially loaded into a robotic drive also referred to herein as a device module 32 such as an EMD drive. An EMD support 79 is removably applied to EMD 102 from a non-axial direction. Robotic drive 32 is operatively coupled to collet 112 to translate and/or rotate collet 112 and EMD 102. In one embodiment EMD 102 is removably and releasably loaded into the robotic drive 32.
In one embodiment collet 112 is in robotic drive 32 when EMD 102 is radially loaded into robotic drive 32. In one embodiment collet 112 is removably inserted into robotic drive 32 with EMD 102 fixed to collet 112.
In one embodiment EMD support 79 limits buckling and prevents kinking of EMD 102 along its length as EMD 102 is being translated and/or rotated.
In one embodiment a robotic system includes a robotic drive 32 or device module includes a drive module 68 or base having a drive coupler 130, and a cassette 66 removably secured to the drive module 68. Collet 112 in cassette 66 is removably fixed to EMD 102. Collet 112 has a driven member 136 operatively coupled to drive coupler 130. The robotic drive 32 includes a motor or actuator operatively coupled to collet 112 to move collet 112. In one embodiment cassette 66 is removably secured to base 68 by directly connecting cassette 66 to base 68. In one embodiment cassette is 66 is removably secured to base 68 indirectly in which an intermediate member is positioned between cassette 66 and base 68.
EMD 102 may be radial loaded or axially loaded into collet 112 prior to collet 112 being positioned within cassette 66 such that EMD 102 and collet 112 are loaded into cassette 66 together. EMD 102 may be radial loaded or axially loaded into collet 112 or when collet 112 is already positioned within cassette 66.
In one embodiment EMD 102 is removably received in collet 112 in a radial direction and collet 112 is removably received and positioned in cassette 66. As described herein collet 112 may have a slot extending from an outer periphery of a collet body extending to its internal pathway. A portion of EMD 102 such as a shaft portion may be inserted into the pathway through the slot in a radial direction. The shaft portion of EMD 102 is a portion of the EMD 102 intermediate a proximal end of EMD 102 and a distal end of EMD 102. Radial loading of the shaft portion of EMD 102 into the collet occurs while the proximal end of EMD 102 and the distal end of EMD 102 remain outside of the collet and pathway. Stated another way shaft portion of EMD 102 is loaded in a direction generally perpendicular to a longitudinal axis of collet 112.
In one embodiment EMD 102 is removably received in collet 112 in an axial direction and collet 112 is removably received in cassette 66. In this embodiment one of the distal end or proximal end of EMD 102 is inserted into a distal opening or proximal opening collet 112 and moved along the longitudinal axis of collet 112 until the distal end or proximal end of EMD exits the other of the distal end or proximal end of collet.
In one embodiment EMD 102 is removably received in collet 112 in a radial direction and collet 112 is non-removably positioned within cassette 66. In one embodiment EMD 102 is removably received in collet 112 in an axial direction and collet 112 is non-removably positioned within cassette 66. In one embodiment collet 112 includes a locating feature 408 that is located within cassette 66 with a locating feature 133 that allows for radial loading as well as rotation of the collet within the cassette 66. In one embodiment collet 112 also includes a distal end that that is located within a locating feature in cassette 66.
Referring to
In one embodiment robotic system includes a clamp releasably clamping a shaft portion of the EMD independent of the collet. In one embodiment the clamp includes at least one tire.
As discussed in more detail herein in one embodiment moving collet 112 rotates the collet and EMD. In one embodiment EMD 102 is selectively rotated in a clockwise and counterclockwise direction about a longitudinal axis of EMD 102.
As discussed in more detail herein in one embodiment moving collet 112 selectively pinches and unpinches the EMD within the collet. In one embodiment as discussed in detail herein moving collet 112 includes moving only one or more parts of collet 112 and not the entire collet to pinch and unpinch the EMD.
As discussed in more detail herein in one embodiment moving collet 112 selectively translates the collet and EMD in a first direction and opposite second direction along a longitudinal axis of the EMD.
As discussed in more detail herein in one embodiment moving collet 112 includes rotating the collet and EMD, translating the collet and EMD and selectively pinching and unpinching the EMD within the collet.
Referring to
EMD 102 may be pinched by on-device adapter and/or collet 112 by manually manipulating collet 112 and then the collet and EMD are robotically rotated and translated. In one embodiment EMD 102 is robotically pinched and unpinched by collet 112 as well as robotically rotated and translated by rotating and translating collet 112.
A number of robotic EMD drive systems are described herein. Additionally, a number of collet designs are also described herein. The specific collet designs described herein, and collet designs known in the art may be used in the various EMD drive systems described. Collets as described herein may also referred to in the art as a pin vise, chuck, bushing, or guidewire torquer.
Referring to
In one embodiment load sensor 120 is the sole support of the load-sensed component 118 in at least one direction of load measurement. In one embodiment cassette housing 104 and isolated component 106 are internally connected so they form one component. In one embodiment a flexible membrane 108 connects cassette housing 104 and isolated component 106, where flexible membrane 108 applies negligible forces in the X-direction (device direction) to the isolated component 106. In one embodiment, flexible membrane 108 is not a physical membrane and represents the cassette interaction.
Referring to
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In one embodiment a mechanical fastener or plurality of fasteners secure the first component 106a to the second component 106b of the isolated component 106. In one embodiment the first component 106a and second component 106b are secured together using magnets. In one embodiment the first component 106a and second component 106b of the isolated component 106 are secured with an adhesive. In one embodiment the first component 106a and second component 106b are releasably secured to one another without the use of tools. In one embodiment the first component 106a and second component 106b are non-releasably secured to one another.
Referring to
In one embodiment the on-device adapter 112 is spaced from and in non-contact with the cassette housing 104 when the on-device adapter 112 is coupled to the load-sensed component 118. In one embodiment the isolated component 106 is separate from the cassette housing 104 in all directions. In one embodiment the isolated component 106 is separate from and in a non-contact relationship with the cassette housing 104.
Referring to
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Cassette housing 104 includes a cradle 132 configured to receive EMD on-device adapter 112 with EMD 102. A cassette bevel gear 134 in cassette housing 104 can freely rotate with respect to cassette housing 104 about an axis aligned with a coupler axis 131 about which coupler 130 of drive module 68 rotates. In the assembled device module 32, cassette 66 is positioned on mounting surface of drive module 68 such that cassette bevel gear 134 receives coupler 130 along coupler axis 131 in such a way that it is free to engage and disengage along coupler axis 131 and integrally connected (not free) about coupler axis 131 such that rotation of coupler 130 corresponds equally to rotation of cassette bevel gear 134. In other words, if coupler 130 rotates clockwise at a given speed, then cassette bevel gear 134 rotates clockwise at the same given speed, and if coupler 130 rotates counterclockwise at a given speed, then cassette bevel gear 134 rotates counterclockwise at the same given speed.
Referring to
In one embodiment the on-device adapter 112 is moved in translation. Referring to
In one embodiment the on-device adapter is moved in rotation about the longitudinal axis of the on-device adaptor.
In one embodiment the on-device adapter 112 includes a collet. Collet can include a variety of collet designs included but not limited to the collets discussed herein. See
Referring to
On-device adapter 112 includes an engagement portion 136 engaged with and driven by a drive member 134 in the cassette 66 to rotate on-device adapter 112. In one embodiment 136 engagement portion is a gear. However other engagement portions that are driven by drive members are contemplated.
In one embodiment on-device 112 adapter includes a surface 408 that is supported by a bearing member in the cassette.
In one embodiment the on-device 112 adapter includes a thrust bearing surface 410 preventing translational movement relative to a portion of cassette 66. In one embodiment the thrust bearing surface 410 includes a first portion 412 preventing translational movement in the distal direction and a second portion 414 preventing translation movement in the proximal direction. In one embodiment first portion 412 and second portion 414 form a groove therebetween defining surface 408 that is supported by a bearing member 133 in cassette 66.
In one embodiment the on-device adapter 112 includes a luer connector 416. In one embodiment luer connector 416 is covered by ISO 80369-7 standard incorporated herein by reference. In one embodiment luer connector 416 is configured to allow the on-device 112 adapter to be flushed with a cleaning fluid. Luer connector has a passage therethrough connected with a passage in the on-device adapter 112. In one embodiment the passage is in the luer connector 416 is co-axial and in fluid communication with the passageway in the on-device adapter. In one embodiment the passage in the on-device adapter 112 is the passage that receives the shaft of the EMD 102. In one embodiment luer connector 41 is a generic connector and in one embodiment it is a connector that falls within ISO 80369-7. In one embodiment luer connector is a luer lock.
Referring to
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In one embodiment the EMD 102 is removably received in the collet 112 in a radial direction and the collet 112 is removably received and positioned in the cassette. In one embodiment the EMD 102 is removably received in the collet 112 in an axial direction and the collet is removably received in the cassette. In one embodiment the EMD is removably received in the collet 112 in a radial direction and the collet 112 is non-removably positioned within cassette. In one embodiment the EMD 102 is removably received in the collet 112 in an axial direction and the collet 112 is non-removably positioned within the cassette.
Referring to
In one embodiment the EMD is a guidewire. In one embodiment the EMD is a catheter having a hub at a proximal end of the catheter and a flexible shaft extending from the hub toward the distal end of the catheter, wherein the shaft is more flexible than the hub. In one embodiment the catheter includes an intermediary portion between the hub and the shaft that has an intermediate flexibility that is less rigid than the hub and more rigid than the shaft.
Referring to
Catheter hub 514 includes a hub body 524 and in one embodiment includes a pair of wings 526 extending radially outward from hub body 524. Referring to
In one embodiment, hub 514 includes a first port to provide access to the inner lumen 534 of the catheter shaft 516 either directly or through hub shaft lumen 534. In one embodiment hub 514 includes an additional port in fluid communication with a lumen of the catheter that may for example be used for inflation of a balloon.
Shaft 516 includes a lumen 534 in fluid communication with a hub lumen 536. Connector 528 includes a lumen in fluid communication with hub lumen 536 and/or shaft lumen 534. Another EMD such as a guidewire may enter an opening in connector 528 and extend therethrough into lumen 536 of the hub and lumen 534 of the shaft. In one embodiment strain relief portion surrounds a proximal portion of shaft lumen 534. Connector 528 also allows for a fluid to be introduced therethrough into the hub lumen 536 and shaft lumen 534 to either flush out the catheter and/or provide fluid to and through the distal end of the catheter shaft 516.
To describe how catheter 512 interacts with another distal catheter, catheter 512 and its features will be referred to as the first catheter and first feature and a distal catheter and its features will be referred to as a second catheter or second feature. First shaft 516 has a given outer diameter to allow first shaft 516 to enter into a second lumen of a second catheter (not shown) and into the vasculature of a patient for diagnostic or therapeutic purposes. The outer diameter of first shaft 516 is less than the inner diameter of a second lumen of the second catheter and thereby can be inserted therein. Note that a guide catheter typically goes into an introducer sheath and not another catheter. Accordingly, a hub of a guide catheter has a geometry such that it cannot enter the introducer sheath and the patient's vasculature.
In contrast, the first hub 514 is not designed to enter into the second lumen of the second catheter or for that matter into introducer sheath lumen. In one embodiment first hub 514 has an outer periphery with a cross section at one location taken perpendicular to the longitudinal axis of the hub and/or catheter that is greater than the inner diameter of the second lumen of the a second catheter hub and/or second lumen of the second catheter. Therefore, the first hub 514 cannot enter into the second lumen of the second catheter. Further the first hub 514 geometry does not permit the proximal end of the catheter to enter into the vasculature.
Shaft 516 has a flexibility sufficient to allow the shaft 516 to bend within either a second lumen of a second catheter through which it enters and/or to allow the shaft to follow a non-straight path of the second catheter. In one embodiment the shaft 516 has flexibility sufficient to allow the shaft to bend within and follow a path of non-straight vasculature.
In one embodiment, a shaft 516 could include a stainless steel hypotube but still have sufficient flexibility to follow the non-straight path of a second catheter through which the shaft extends and/or a patient's non-straight vasculature.
In one embodiment connector 528 is a luer connector and in one embodiment the luer connector is a female luer connector. In one embodiment the luer connector has a lumen in fluid communication with the lumen of the hub to allow another EMD to pass therethrough or to allow fluid to enter the hub and catheter through the luer connector.
In one embodiment hub wings 526 are used by an operator in manual operation to hold on to hub 524. Wings 526 may be used a location device within cavity 520 of on-device adapter 510.
In one embodiment hub 514 is free of controls used to manipulate features within catheter 512 such as a wire extending to the distal end of the catheter to deflect the tip. In one embodiment catheter 512 does not include any controls used to manipulate features within the catheter such as a wire extending to the distal end of the catheter to deflect the tip.
In one embodiment on-device adapter 510 is configured to pinch an EMDs having a range of shaft outer diameters. In one embodiment a Merit Medical torque device is used as part of the on-device adapter to cover one of the following outer shaft diameter ranges: 0.009″ to 0.018″, 0.018″ to 0.038″, 0.010″ to 0.020″, 0.013″ to 0.024″, or 0.025″ to 0.040″. Where the symbol “ designates inches. Note that the torque devices provided by Merit Medical have overlapping ranges.
In one embodiment, more than one on-device adapter is used with the robotic drive system depending on the outer diameter of the shaft of the EMD to be pinched.
In one embodiment where the robotic system is controlling more than one EMD a first on-device adapter is used for a first EMD having a first outer diameter and a second on-device adapter is sued for a second EMD having a second outer diameter different than the first outer diameter of the first EMD. For example, A first on-device adapter is used to o pinch an angiographic guidewire having an outer diameter of 0.035″ or 0.038″ and the second on-device adapter is sued to pinch a microwire having an outer diameter of approx. 0.014″. An angiographic guidewire, which is used get the guide catheter in place is also called a diagnostic guidewire. And a microwire could be referred to as a micro-guidewire or simply a guidewire. For clarity the term approx. used herein is an abbreviation for the word approximately.
In one embodiment, the on-device adapter does not need to be designed to be disassembled. In one embodiment, the on-device adapter may be designed to accept a single torquer. Note that the terms torquer and torque device are used interchangeably herein and are a subset of a collet as used herein. In one embodiment, the on-device adapter provides sufficient clamping force on the torque device to withstand axial force when the on-device adapter is being advanced and retracted and withstand torsional force when the on-device is being rotated to rotate an EMD for a given procedure. The pinch or clamping force applied to the torquer by the on-device adapter is sufficient to resist slippage (axial or rotational) of the EMD being advanced and/or rotated along with the on-device adapter. In one embodiment, the on-device adapter penetrates an outer surface of the torque device body and/or deforms a surface of the torque device.
Referring to
EMD robotic system 910 includes a collet employing a double-gear arrangement that releasably engages EMD 912 and rotates and translates EMD 912. In one embodiment the double-gear arrangement includes double-bevel gears. The double-gear collet-drive system 910 has a proximal end 911 and a distal end 913. As EMD 912 is moved from the proximal end 911 toward the distal end 913 the EMD 912 is being advanced into the patient and when the EMD 912 is moved from the distal end 913 toward the proximal end the EMD 912 is being retracted or withdrawn from the patient. In order to clarify directions, a rectangular coordinate system is introduced with X, Y, and Z axes. The positive Z axis is oriented in a longitudinal (axial) distal direction, that is, in the direction from the proximal end to the distal end. The X and Y axes are in a transverse plane to the Z axis, with the positive Y axis oriented up, that is, in the direction opposite of gravity, and the X axis in a direction toward the front (typically pointing toward the operator/physician who is bedside). The right-hand rule is adopted to determine the sense of rotational direction, that is, the orientation convention is determined by pointing the thumb of the right hand along the positive X, Y, and Z axis direction and then the curl of the fingers of the right hand is associated with the clockwise direction. The direction opposite the curl of the fingers of the right hand is associated with the counterclockwise direction. The terms clockwise and counterclockwise as used herein are relative terms indicating a first direction of rotation and a second direction of rotation that is opposite to the first direction of rotation. Accordingly, any use of the term clockwise and counterclockwise are to be understood to mean a first direction of rotation and a second opposing direction of rotation. The terms clockwise and counterclockwise have been used to assist in following the different rotational directions of the devices provided herein, however it is possible that the devices could be constructed with the clockwise and counterclockwise directions are reversed.
The collet-drive system 910 includes a drive module 914 that translates along an axial direction of EMD 912 and is actuated by a drive module translational drive 916. Drive module 914 includes a drive module housing 918, a mount bracket 920, a cassette 922, and a cassette cover 924. The cassette 922 includes a double-gear collet-drive housing 926 and EMD guides 928. The top of the double-gear collet-drive housing 926 includes multiple openings 927 and multiple ribs 929. The EMD guides 928 include multiple pairs of guides that act as v-shaped notches and serve as an open channel for guiding EMD 912 through the drive system. Note that the open channel is open for loading but covered when the cassette cover is in the closed position. The guides act as anti-buckling features. In one embodiment EMD guides 928 include multiple pairs of v-shaped notches or u-shaped channels that act as guides. The tops of the v-shaped or u-shaped channels may be chamfered to assist in loading the EMD 912. In one embodiment one pair of EMD guides 928 is used on the proximal side of the double-gear collet-drive housing 926 and one pair of EMD guides 928 is used on the distal side of the double-gear collet-drive housing 926. In one embodiment multiple pairs of EMD guides 928 are used on the proximal side of the double-gear collet-drive housing 926 and multiple pairs of EMD guides 928 are used on the distal side of the double-gear collet-drive housing 926.
In one embodiment robotic system 910 includes a third motor 932 (not shown) operatively coupled to collet 964 to translate collet 964 and EMD 912 along a longitudinal axis of collet 964. In one embodiment first motor 936 and second motor 938 are fixed relative to collet 964 during translation of the collet and EMD. The drive module translational drive 916 includes a lead screw 930 driven by a screw drive motor 932 (not shown) inside of a screw drive housing 934. The screw drive 930 is used to translate drive module 914 relative to fixed housing 934. In one embodiment screw drive motor 932 is a stepper motor. In one embodiment screw drive motor 932 is a servo motor. In one embodiment screw drive motor 932 is a rotational actuator powered by electrical, pneumatic, hydraulic, or other means.
In one embodiment drive module housing 918 and its contents are reusable. In one embodiment cassette 922 is consumable and meant to be disposed of after use with a single patient. In one embodiment cassette 922 may be made of a material that is sterilizable and reused.
Referring to
First coupler 940 passes through drive module housing 918 and is integrally connected to a first coupler bevel gear 946. Second coupler 942 passes through mount bracket 920 and is integrally connected to a second bevel gear 948. First motor 936, first coupler 940, and first coupler bevel gear 946 are located distally in the drive module housing 918. Second motor 938, second coupler 942, and second coupler bevel gear 948 are located proximally in the drive module housing 918. In one embodiment first coupler 940 and second coupler 942 pass through holes in mount bracket 920. In one embodiment first coupler 940 and second coupler 942 pass through rotational bearings that are mounted in mount bracket 920.
The collet-drive housing 926 contains a double-gear collet-drive assembly 944, described herein.
Referring to
In one embodiment a top face 947 of first coupler bevel gear 946 includes an open central hole along its central axis to receive and drive first coupler 940. Stated another way gear 946 has a hole along its longitudinal axis. In one embodiment top face 947 of first coupler bevel gear 946 is not open but sealed to prevent migration of fluids from the cassette into the base. In one embodiment a top face 949 of second coupler bevel gear 948 includes an open central hole along its central axis to receive and drive second coupler 942. In one embodiment top face 949 of second coupler bevel gear 948 is not open but sealed to prevent migration of fluids from the cassette into the base.
In one embodiment cassette 922 is removably secured to the base 914. Collet 964 is positioned within cassette 922. The first collet coupler 958 and the second collet coupler 960 are respectively coupled to the first motor 936 and the second motor 938 via a first drive coupler 940 and a second drive coupler 942 positioned within the base 914. In one embodiment first drive coupler 940 includes a shaft operatively connected to motor 936 and extending from the base in a sealed manner and is operatively connected to gear 946 that is operatively engaged with first collet coupler 958. Similarly, second drive coupler 942 includes a shaft operatively connected to motor 938 and extending from the base in a sealed manner and is operatively connected to gear 948 that is operatively engaged with second collet coupler 960.
The first compound assembly 958 contains a radial longitudinal slit 962 extending from an outer surface of the assembly and terminating at its radial center. The second compound assembly 960 contains a radial longitudinal slit 963 extending from an outer surface of the assembly and terminating at its radial center. Slits 962 and 963 allow for side or radial loading of EMD 912. In one embodiment slits 962 and 963 create radial openings with opposing nonparallel walls. In one embodiment slits 962 and 963 create approximately radial openings with opposing parallel walls. In one embodiment the outer surfaces of assemblies 958 and 960 contain v-shaped notches directed toward their center longitudinal axes that lead into the slits 962 and 963, respectively, to help guide EMD 912 for side or radial loading. It is noted that slit 962 extends through first driven bevel gear 950 and slit 963 extends through second driven bevel gear 952. First coupler bevel gear 946 meshes with and drives first driven bevel gear 950 with slit 962 without compromising performance. Second coupler bevel gear 948 meshes with and drives second driven bevel gear 952 with slit 963 without compromising performance.
Referring to
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Screw spline 966 includes a screw spline first section 976 integrally connected to a screw spline second section 978. The screw spline first section 976 contains external longitudinal spline threads 980 that mesh with the internal longitudinal spline threads 982 of the second compound assembly 960 and allow for relative translational motion in the longitudinal direction 988. The screw spline second section 978 contains external spiral circumferential screw threads 984 that mesh with internal screw threads 986 of the first compound assembly 958 and allow for relative rotational motion in the clockwise or counterclockwise directions 990. The design of the screw spline 966 with both longitudinal spline threads 980 and spiral circumferential screw threads 984 allows the screw spline 966 to be rotated and translated relative to the inner collet portion 965 while maintaining fixed longitudinal distances between first driven coupler bevel gear 950 and second driven coupler bevel gear 952 such that they can mesh, respectively with first coupler bevel gear 946 and second coupler bevel gear 948.
In one embodiment EMD 912 does not rotate while EMD 912 is being pinched and unpinched. Collet first section 968 is the section that releasably fixes EMD 912 thereto. By maintaining collet first section 968 stationary while rotating second section 966 portion EMD 912 does not rotate. Stated another way, unpinching of EMD from collet 964 without imparting any rotation to EMD 912 about the longitudinal axis of collet 964 is accomplished by maintaining internal collet portion 965 of the collet that is in direct fixed contact with EMD 192 stationary relative to the patient as outer collet portion 966 is rotated relative to inner collet portion 965 releasing EMD 192 from a fixed relationship to inner collet 965. In one embodiment it may desirable to continue to rotate EMD 912 during the beginning of the unpinch process. In this embodiment first collet section 968 rotates at a different rate than outer collet portion 966.
Referring to
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In operation double-gear collet-drive assembly 944 uses two rotational degrees of freedom from motors 936 and 938 to achieve four operations, namely, to pinch EMD 912, to unpinch EMD 912, to rotate clockwise double-gear collet-drive assembly 944, and to rotate counterclockwise double-gear collet-drive assembly 944. The four operations occur by movement of inner collet portion 965 relative to screw spline 966 based on rotation direction of first coupler 940 and rotation direction of second coupler 942.
In a first mode of operation, in which the result is the double-gear collet-drive assembly 944 rotates in a clockwise direction, first coupler 940 rotates in a counterclockwise direction and second coupler 942 rotates in a clockwise direction. In a second mode of operation, in which the result is the double-gear collet-drive assembly 944 rotates in a counterclockwise direction, first coupler 940 rotates in a clockwise direction and second coupler 942 rotates in a counterclockwise direction. In a third mode of operation, in which the result is the EMD 912 is unpinched, first coupler 940 does not rotate and second coupler 942 rotates in a counterclockwise direction. In a fourth mode of operation, in which the result is the EMD 912 is pinched, first coupler 940 does not rotate and second coupler 942 rotates in a clockwise direction. In the third mode and fourth mode of operations, the collet becomes unpinched or pinched, respectively. In one embodiment in the third mode and the fourth mode motion continues until a hard stop is reached. In one embodiment in unpinching a hard stop is reached when arriving at the end of the spline threads on the screw spline first section 976. In one embodiment in pinching a hard stop is reached when arriving at the end of the threads on the screw spline second section 978 where it meets the screw spline first section 976. For faster initiation of rotation of EMD during pinch during the fourth mode, first coupler 940 is rotated clockwise.
First motor 936 and second motor 938 can be controlled to constrain the amount of torque that each motor can apply. In one embodiment in which first motor 936 and second motor 938 are servomotors, each motor can be controlled with current limits to constrain the torque that each motor can apply. Current limits can be set at different values for the third mode and fourth mode of operations. For example, the currents can be limited to lower values for pinching than for unpinching since in unpinching static friction must be overcome.
In one embodiment double-gear collet-drive system 910 incorporates a system to prevent buckling of EMD 912 at the proximal end 911 of the collet-drive system. In one embodiment double-gear collet-drive system 910 incorporates a system to prevent buckling of EMD 912 at the distal end 913 of the collet-drive system. In one embodiment the system to prevent buckling is a tube with an inner diameter slightly larger than the outer diameter of EMD 912. In one embodiment the system to prevent buckling is a set of telescoping tubes with the inner diameter of the smallest tube slightly larger than the outer diameter of EMD 912. In one embodiment the system to prevent buckling is a side-loadable track.
Referring to
Sliding collet-drive system 1000 includes a carrier 1008 that translates along an axial direction of EMD 1002 actuated by a carrier translational drive 1010 that is mounted to a fixed base 1012. Carrier 1008 includes a carrier housing 1014, a carrier arm 1016, and a rack 1018, all three of which are integrally connected. Carrier translational drive 1010 includes a pinion gear 1020 integrally connected to a motor shaft (not shown) of translational drive motor 1022. Translational drive motor 1022 rotates pinion gear 1020 that meshes with rack 1018 to translate carrier 1008. Linear guides or linear bearings (not shown) integrally connected to base 1012 constrain carrier 1008 to translational motion only in the proximal and distal directions along EMD 1002 axis.
Carrier housing 1014 includes a flat base plate with perpendicular side extensions on its proximal and distal ends. In one embodiment carrier housing 1014 is one integrated piece with base plate, proximal extension, and distal extension made of the same material. In one embodiment carrier housing 1014 includes a base plate, a proximal extension, and a distal extension as three separate pieces made of the same material that are integrally connected. In one embodiment carrier housing 1014 includes a base plate, a proximal extension, and a distal extension as three separate pieces made of different materials that are integrally connected. The proximal and distal extensions of carrier housing 1014 include holes that support a collet-and-rotational-drive system 1024 (described below). In one embodiment rotational bearings are mounted in the holes in the proximal and distal extensions of carrier housing 1014.
A first motor 1026 and a second motor 1028 are mounted to fixed base 1012. In one embodiment first motor 1026 and second motor 1028 are fixed relative to base 1012 during translation of collet 1056 and EMD 1002. As described herein carrier 1008 is translated with collet 1056 independently of base 1012 and first motor 1026 and second motor 1028. Stated another way, at least during one mode of operation when collet 1056 is translated along its longitudinal axis the first motor 1026 and second motor 1028 are not translated with collet 1056. First motor 1026 drives a first coupler 1030. Second motor 1028 drives a second coupler 1032. First motor 1026 and first coupler 1030 are located below or within base 1012. Second motor 1028 and second coupler 1032 are located proximally below fixed base 1012. In one embodiment first coupler 1030 and second coupler 1032 pass through holes in the fixed base 1012. In one embodiment first coupler 1030 and second coupler 1032 pass through rotational bearings and seals that are mounted in the fixed base 1012.
In one embodiment translational drive motor 1022, first motor 1026, and second motor 1028 are stepper motors however other motor types known in the art are also contemplated. In one embodiment translational drive motor 1022, first motor 1026, and second motor 1028 are servo motors. In one embodiment translational drive motor 1022, first motor 1026, and second motor 1028 are rotational actuators powered by electrical, pneumatic, hydraulic, or other means.
Referring to
Translation of collet-and-rotational-drive system 1024 is accomplished without needing to translate first motor 1026 (and first coupler 1030 and first driver bevel gear 1034) and second motor 1028 (and second coupler 1030 and second driver bevel gear 1042), both of which are mounted to fixed base 1012. Hence, inertial issues of translational acceleration and translational deceleration of first motor 1026 and second motor 1028 are avoided.
Referring to
First collet spur gear 1050 and second collet spur gear 1052 are wide gears, that is, they are elongated gears wider than the widths of first spur gear 1038 and second spur gear 1046. In one embodiment the widths of first collet spur gear 1050 and second collet spur gear 1052 are ten times the widths of first spur gear 1038 and second spur gear 1046, respectively. In one embodiment the widths of first collet spur gear 1050 and second collet spur gear 1052 are less than ten times the widths of first spur gear 1038 and second spur gear 1046, respectively. In one embodiment the widths of first collet spur gear 1050 and second collet spur gear 1052 are greater than ten times the widths of first spur gear 1038 and second spur gear 1046, respectively.
First compound gear assembly 1040 and second compound gear assembly 1048 are supported relative to base 1012 in such a way that they are coaxially aligned and can rotate about a longitudinal axis. In one embodiment first shaft 1037 connecting first driven bevel gear 1036 and first spur gear 1038 passes through and is supported by a hole in an extension from base 1012. In one embodiment first shaft 1037 connecting first driven bevel gear 1036 and first spur gear 1038 passes through and is supported by a rotational bearing in an extension from base 1012. In one embodiment second shaft 1045 connecting second driven bevel gear 1044 and second spur gear 1046 passes through and is supported by a hole in an extension from base 1012. In one embodiment second shaft 1045 connecting second driven bevel gear 1044 and second spur gear 1046 passes through and is supported by a rotational bearing in an extension from base 1012.
Referring to
In one embodiment first collet spur gear 1050 is integrally connected to a first wheel (not shown) that has a larger diameter than that of spur gear 1050 and second collet spur gear 1052 is integrally connected to a second wheel (not shown) that has a larger diameter than that of spur gear 1052. The first wheel and second wheel would be accessible for manual manipulation by an operator. For example, in the event of a power loss the operator could manually rotate the first wheel and second wheel for removal of EMD 1002. In one embodiment the first wheel and second wheel are circular disks with notches on their outer circumferential peripheries. In one embodiment the first wheel and second wheel are circular disks with grooves on their outer circumferential peripheries. In one embodiment the first wheel and second wheel are circular disks with teeth on their outer circumferential peripheries. In one embodiment the first wheel and second wheel are circular disks with features that aid in manual manipulation on their outer circumferential peripheries. In one embodiment the first wheel and second wheel are circular disks with no features, such as smooth walls, on their outer circumferential peripheries. In one embodiment first collet spur gear 1050 and the first wheel are a single integrated component made of the same material and second collet spur gear 1052 and the second wheel are a single integrated component made of the same material. In one embodiment first collet spur gear 1050 and the first wheel are separate components integrally combined and second collet spur gear 1052 and the second wheel are separate components integrally combined.
In one embodiment carrier arm 1016 can be manually removed from the proximal side of carrier housing 1014 and reconnected to the proximal side of carrier housing 1014 due to snap fit features built into the proximal side of carrier housing 1014. In one embodiment carrier arm 1016 can be manually removed from rack 1018 and reconnected to rack 1018 due to snap fit features built into the distal side of rack 1018.
In one embodiment collet-and-rotational-drive 1024 is consumable. In one embodiment collet-and-rotational-drive 1024 and carrier 1008 are consumable. In one embodiment collet-and-rotational-drive 1024 and carrier housing 1014 are consumable. In one embodiment collet-and-rotational-drive 1024, carrier housing 1014, and carrier arm 1016 are consumable.
Referring to
Collet inner member 1056 is comprised of a first section 1060 and a second section 1062. First section 1060 of collet inner member 1056 has a cylindrical collar or sleeve shape with the center of its longitudinal axis colinear with the axis of EMD 1002 and with its outer circumferential surface integrally connected to the internal wall 1064 of first collet spur gear 1050. Second section 1062 of collet inner member 1056 has a tapered shape toward the center longitudinal axis with an internal lumen. In one embodiment second section 1062 of collet inner member 1056 includes two separated tapered jaws. In one embodiment second section 1062 of collet inner member 1056 includes more than two separated tapered jaws. In one embodiment first section 1060 and second section 1062 of collet inner member 1056 and first collet spur gear 1050 are one integrated piece. In one embodiment first section 1060 and second section 1062 of collet inner member 1056 and first collet spur gear 1050 are separate pieces that are integrally connected.
Collet outer member 1058 is comprised of a first section 1066 and a second section 1068. First section 1066 of collet outer member 1058 has a cylindrical collar or sleeve shape with the center of its longitudinal axis colinear with the axis of EMD 1002 and with its outer circumferential surface integrally connected to the internal wall 1070 of second collet spur gear 1052. Second section 1068 of collet outer member 1058 has a cylindrical collar or sleeve shape with external screw threads 1074 on its outside circumference and with the center of its longitudinal axis colinear with the axis of EMD 1002. In one embodiment first section 1066 and second section 1068 of collet outer member 1058 and second collet spur gear 1052 are one integrated piece. In one embodiment first section 1066 and second section 1068 of collet outer member 1058 and second collet spur gear 1052 are separate pieces that are integrally connected.
The external screw threads 1074 of second section 1068 of collet outer member 1058 mesh with internal screw threads 1072 of second section 1062 of collet inner member 1056. Due to meshing of internal screw threads 1072 with external screw threads 1074 rotation of collet inner member 1056 relative to collet outer member 1058 about a longitudinal axis corresponds to translation of collet inner member 1056 relative to collet outer member 1058 along a longitudinal axis. Since first collet spur gear 1050 is integrally connected to collet inner member 1056 and second collet spur gear 1052 is integrally connected to collet outer member 1058, rotation of first collet spur gear 1050 relative to second collet spur gear 1052 about a longitudinal axis corresponds to translation of first collet spur gear 1050 relative to second collet spur gear 1052 along a longitudinal axis. Rotation of first collet spur gear 1050 is accomplished by its mesh with first spur gear 1038. Rotation of second collet spur gear 1052 is accomplished by its mesh with second spur gear 1046.
To ensure continuous meshing between first collet spur gear 1050 and first spur gear 1038, first collet spur gear 1050 is made wider than first spur gear 1038. This is needed to accommodate the translation of first collet spur gear 1050 as it is rotated by first spur gear 1038 and to accommodate the translation of first collet spur gear 1050 as it is translated by carrier 1008. To ensure continuous meshing between second collet spur gear 1052 and second spur gear 1046, second collet spur gear 1052 is made wider than second spur gear 1046. This is needed to accommodate the translation of second collet spur gear 1052 as it is rotated by second spur gear 1046 and to accommodate the translation of second collet spur gear 1052 as it is translated by carrier 1008. In one embodiment first collet spur gear 1050 and second collet spur gear 1052 remain engaged with the first motor 1026 and second motor 1028 during translation of collet 1054. Stated another way first collet spur gear 1050 includes teeth having a face width of sufficient length to permit engagement of the teeth of gear 1050 with gear 1038 as gear 1050 is translated along with collet 1054 with respect to motor 1026. Similarly, second collet spur gear 1052 includes teeth having a face width of sufficient length to permit engagement of the teeth of gear 1052 with gear 1046 as gear 1052 is translated along with collet 1054 with respect to motor 1028.
Referring to
The principle of operation of the collet-and-rotational-drive system 1024 is similar to that of the collet of the double-gear collet-drive assembly 944 of
In operation the double-gear collet-and-rotational drive system 1024 uses two rotational degrees of freedom from motors 1026 and 1028 to achieve four operations, namely, to pinch EMD 1002, to unpinch EMD 1002, to rotate clockwise double-gear collet-and-rotational drive system 1024, and to rotate counterclockwise double-gear collet-and-rotational drive system 1024. The four operations occur by movement of collet inner member 1056 relative to collet outer member 1058 based on rotation direction of first coupler 1030 and rotation direction of second coupler 1032.
In a first mode of operation, in which the result is the double-gear collet-and-rotational drive system 1024 rotates in a clockwise direction, first coupler 1030 rotates in a clockwise direction and second coupler 1032 rotates in a counterclockwise direction. In a second mode of operation, in which the result is the double-gear collet-and-rotational drive system 1024 rotates in a counterclockwise direction, first coupler 1030 rotates in a counterclockwise direction and second coupler 1032 rotates in a clockwise direction. In a third mode of operation, in which the result is the EMD 1002 is unpinched, first coupler 1030 rotates in a clockwise direction and second coupler 1032 rotates in a clockwise direction. In a fourth mode of operation, in which the result is the EMD 1002 is pinched, first coupler 1030 rotates in a counterclockwise direction and second coupler 1032 rotates in a counterclockwise direction. In the third mode and fourth mode of operations, collet inner member 1056 unpinches or pinches, respectively, EMD 1002 until a hard stop is reached.
In one embodiment pinching and unpinching of collet mechanism 1054 is synchronized with the rotational position of the shaft of translational drive motor 1022.
In one embodiment, components of the double-gear sliding collet-drive system 1000 contain longitudinal slits (not shown) to enable radial or side loading of EMD 1002 into collet lumen 1076.
Robotic system 1000 in one embodiment includes a pinch/unpinch mode, a rotation mode and a translation mode. The pinch/unpinch mode, rotation mode and translation mode may occur individually or simultaneously. In one embodiment rotation mode and the translation mode occur simultaneously.
Referring to
The proximal and distal sides of the cassette cover 1084 include cover notches 1088 that allow for free passage of EMD 1002. The proximal and distal sides of the cassette housing 1086 include housing notches 1090 that match the positions of cover notches 1088. In one embodiment cover notches 1088 and housing notches 1090 are triangular-shaped cutouts that allow for free passage of EMD 1002. In one embodiment cover notches 1088 and housing notches 1090 are arbitrarily shaped cutouts that allow for free passage of EMD 1002. The underside of cassette cover 1084 includes cover ribs 1092. When cassette cover 1084 is closed cover ribs 1092 seat EMD 1002 into alignment notches 1090 in cassette housing 1086 and maintain EMD 1002 vertical position in said alignment grooves or channels that maintain EMD 1002 lateral position.
As described above the collet-and-rotational-drive system 1024 is actuated by a first motor 1026 driving a first coupler 1030 and a second motor 1028 driving a second coupler 1032. The reset mechanism 1082 is actuated by a reset mechanism motor 1094 that drives a reset mechanism coupler 1096. In one embodiment reset mechanism motor 1094 is a stepper motor. In one embodiment reset mechanism motor 1094 is a servo motor. In one embodiment reset mechanism motor 1094 is a rotational actuator powered by electrical, pneumatic, hydraulic, or other means.
Referring to
A proximal first linear bearing 1118 and a distal first linear bearing 1120 are integrally mounted to the front corners of reset mechanism frame 1098. A proximal second linear bearing 1122 and a distal second linear bearing 1124 are integrally mounted to the rear corners of reset mechanism frame 1098. First guide 1114 can translate relative to proximal first linear bearing 1118 and distal first linear bearing 1120. Second guide 1116 can translate relative to proximal second linear bearing 1122 and distal second linear bearing 1124. Since the four bearings 1118, 1120, 1122, and 1124 are integrally mounted to reset mechanism frame 1098, reset mechanism 1082 can translate longitudinally relative to fixed base 1012.
In one embodiment first coupler 1030 has a first coupler slotted end 1126 that seats into a slotted receiver of a shaft integrally connected to first driver bevel gear 1034 and second coupler 1032 has a second coupler slotted end 1128 that seats into a slotted receiver of a shaft integrally connected to second driver bevel gear 1042. (See
Referring to
In operation reset cam 1130 can be in a closed position or an open position. In the closed position reset cam 1130 is in an opposing position relative to holding cam 1132. In one embodiment in the closed position there is no gap between reset cam outer surface 1136 and holding cam outer surface 1138 and the two surfaces 1136 and 1138 are in contact. In one embodiment in the closed position there is a gap between reset cam outer surface 1136 and holding cam outer surface 1138 with the gap distance less than the diameter of EMD 1002. In the closed position EMD 1002 is pinched between reset cam outer surface 1136 and holding cam outer surface 1138, such that EMD 1002 is prevented from translating longitudinally. In one embodiment reset cam outer surface 1136 and holding cam outer surface 1138 include an elastomeric or other deformable or compliant material that deforms about the EMD in the closed position. In the open position reset cam 1130 is rotated away from holding cam 1132 such that there is a gap between reset cam outer surface 1136 and holding cam outer surface 1138. In the open position reset cam 1130 does not contact EMD 1002, such that EMD 1002 is unconstrained to translate longitudinally at the location of holding cam 1132. In one embodiment reset cam 1130 rotates 60 degrees away from holding cam 1132 in the open position. In one embodiment reset cam 1130 rotates less than 60 degrees away from holding cam 1132 in the open position. In one embodiment reset cam 1130 rotates more than 60 degrees away from holding cam 1132 in the open position.
Referring to
Referring to
Referring to
Referring to
Referring to
First lateral face 1292 of housing 1290 has a slit 1300 oriented in the plane defined by EMD axis 1298 and perpendicular axis 1302 extending from face 1292 and terminating at EMD axis 1298 through housing 1290 from second lateral face 1294 to its opposite face. In one embodiment the walls of slit 1300 are parallel. In one embodiment the walls of slit 1300 are nonparallel, such as v-shaped walls with a vertex toward EMD axis 1298. In one embodiment slit 1300 has a lead-in chamfer at first lateral face 1292. In one embodiment slit 1300 has no lead-in chamfer at first lateral face 1292.
Second lateral face 1294 of housing 1290 includes a plunger pin hole 1304 for a plunger pin 1306 (not shown in
Referring to
With EMD 1314 fully inserted into the well of slit 1300 at plunger axis 1286, applied force 1310 is removed. Referring to
Referring to
The bottom of compression spring 1282 is in contact with a bottom inner surface 1330 of cavity 1288 of housing 1290. The top of compression spring 1282 is in contact with a bottom inner surface 1332 of plunger 1284. In one embodiment at the bottom inner surface 1332 of plunger 1284 there is a pocket or cup that receives the top of spring 1282 and constrains the top of spring 1282 by lip 1328. The outer diameter of spring 1282 is smaller than the inner diameter of cavity 1288 at the bottom of housing 1290 to allow freedom for compression. In one embodiment the outer diameter of spring 1282 is smaller than the inner diameter of cavity 1288 at the bottom of housing 1290 and larger than the diameter corresponding to buckling or bending of the spring to prevent buckling or bending of the spring. In one embodiment one compression spring 1282 is utilized. In one embodiment multiple springs, such as two nested springs, are used.
Plunger 1284 includes a plunger slot 1324 oriented along plunger axis 1286 allowing plunger 1284 to translate along plunger axis 1286 relative to housing 1290 constrained by plunger pin 1306 and the walls of the cavity 1288 in housing 1290. To unpinch collet 1280 plunger 1284 is depressed down by application of applied force 1310 to the top surface 1312 of plunger. In operation plunger 1284 is a cam follower with its top surface 1312 being the follower surface in contact with a cam (not shown) pushing down on the cam follower with applied force 1310. An outer member (not shown) with an internal cam is in contact with the top surface 1312 of plunger 1284. By rotation of the outer member relative to housing 1290 the internal cam of the outer member pushes down on the top surface 1312 thereby depressing plunger 1284 and unpinching EMD 1314 in collet 1280.
Referring to
Referring to
Referring to
Referring to
Referring to
Referring to
Referring to
Compared to the torque carrying ability of the multi-plunger collet system 1336 of
The deformation of the EMD 1314 in the pinched configuration of the multi-plunger collet system 1336 is a function of the through hole diameter in the center of the plunger housing, the gap (clearance) between the plunger and plunger housing, and the force applied by the spring mechanism.
In one embodiment a series of pinching elements in a collet for robotic actuation where the pinching elements are independently actuated. The actuation mechanism such as a cam is such that instead of actuating all of the elements together, their actuation is not all together such as sequentially actuated. This feature acts to lower actuation force.
In one embodiment multi-plunger collet system 1336 consisting of multiple pinching elements are rotationally clocked to each other in order to increase the overall torque holding capability of the collet. Rotationally clocked refers to placing the pinching elements at various angles in a plane perpendicular to the longitudinal axis of the collet 1336.
Referring to
Referring to
In one embodiment the longitudinal axis of inner housing 1362 is co-linear with the longitudinal axis of outer housing 1363. In one embodiment at least a portion of outer housing 1363 and/or a portion of inner housing 1362 is arcuate and/or circular. In one embodiment all levers 1366a,b,c, . . . rotate about a single pivot pin 1368. In one embodiment multiple pivot pins 1368a,b,c, . . . are used, where lever 1366a rotates about pin 1368a, lever 1366b rotates about pin 1368b, etc. In one embodiment the plurality of cam surfaces 1365a,b,c, . . . are incrementally spaced along a longitudinal axis around the inner circumference of outer housing 1363. In one embodiment the plurality of cam surfaces 1365a,b,c, . . . are grooves or recesses incrementally spaced along a longitudinal axis around the inner circumference of outer housing 1363.
Circumferential slits 1376a,b,c, . . . of inner housing 1362 are oriented parallel to a plane perpendicular to EMD axis 1370. In the embodiment of
Radial longitudinal slit 1367 of outer housing 1363 extends from an outer surface of outer housing 1363 and terminates at inner surface of internal cavity 1369 of outer housing 1363. The gap between the walls of radial longitudinal slit 1367 is larger than the diameter of an EMD 1388 allowing an EMD 1388 to enter. In one embodiment the walls of radial longitudinal slit 1367 are parallel. In one embodiment the walls of radial longitudinal slit 1367 are nonparallel, such as v-shaped walls with a vertex toward EMD axis 1370. In one embodiment radial longitudinal slit 1367 has a lead-in chamfer at the outer surface of outer housing 1363. In one embodiment radial longitudinal slit 1367 has no lead-in chamfer at the outer surface of outer housing 1363.
Radial longitudinal slit 1374 of inner housing 1362 extends from an outer surface of inner housing 1362 and terminates at its radial center corresponding to EMD axis 1370 and extends longitudinally through inner housing 1362. The gap distance between the walls of radial longitudinal slit 1374 is larger than the diameter of an EMD 1388 allowing an EMD 1388 to enter. In one embodiment the walls of radial longitudinal slit 1374 are parallel. In one embodiment the walls of radial longitudinal slit 1374 slits are nonparallel, such as v-shaped walls with a vertex toward EMD axis 1370. In one embodiment radial longitudinal slit 1374 has a lead-in chamfer at the outer surface of inner housing 1362. In one embodiment radial longitudinal slit 1374 has no lead-in chamfer at the outer surface of inner housing 1362.
Springs 1364a,b,c, . . . are compression springs, such as coil springs, located in the internal cavity 1372 of inner housing 1362. One end of springs 1364a,b,c, . . . is constrained by an internal wall 1378 of cavity 1372 of inner housing 1362. The other end of springs 1364a,b,c, . . . is seated over and extends into protrusions 1380a,b,c, . . . of levers 1366a,b,c, . . . . In one embodiment protrusions 1380a,b,c, . . . of levers 1366a,b,c, . . . extend into one end coil of springs 1364a,b,c, . . . . In one embodiment protrusions 1380a,b,c, . . . of levers 1366a,b,c, . . . extend into more than one end coil of springs 1364a,b,c, . . . . In one embodiment protrusions 1380a,b,c, . . . of levers 1366a,b,c, . . . are operatively connected to one end coil of springs 1364a,b,c, . . . . In one embodiment protrusions 1380a,b,c, . . . of levers 1366a,b,c, . . . are operatively connected to more than one end coil of springs 1364a,b,c, . . . . In one embodiment one compression spring 1364 is used. In one embodiment multiple compression springs are used. In one embodiment, the number of springs equals the number of levers. In one embodiment a collar or sleeve surrounding each spring 1364a,b,c, . . . is used to prevent buckling or bending of the springs.
In the assembled configuration springs 1364a,b,c, . . . are in compression. In operation, cam surfaces 1365a,b,c, . . . on the inner surface (interior wall) of outer housing 1363 operatively engage respective arms 1384a,b,c, . . . of levers 1366a,b,c, . . . that are exposed in slits 1376a,b,c, . . . as outer housing 1363 is rotated about its longitudinal axis relative to inner housing 1362. Referring to
To pinch and unpinch opposing pad collet system 1360 lever 1366a pivots about pivot pin 1368 through a limited range of motion. In one embodiment the angular range of motion of lever 1366a is less than 10 degrees. In one embodiment the angular range of motion is greater than 10 degrees. Lever 1366a acts as a first-class lever with its pivot between an effort and a load. An effort or input force 1382a is applied to an arm 1384a of lever 1366a. A load or output force acts at pad 1386a of lever 1366a.
With EMD 1388 fully inserted into radial longitudinal slit 1374, applied force 1382a is removed. Referring to
Referring to
In operation arm 1384a of lever 1366a is a cam follower with an outer surface of arm 1384a being the follower surface in contact with a cam (inner surface of outer housing 1363) pushing on the cam follower with applied force 1382a. Outer member 1363 with an internal cam is in contact with the outer surface of arm 1384a. By rotation of the outer housing 1363 relative to inner housing 1362 the internal cam of the outer member pushes on the outer surface of arm 1384a, exposed in circumferential slit 1376a, thereby rotating lever 1366a and moving pad 1386a of lever 1366a away from EMD axis 1370 and unpinching EMD 1388 in collet 1360. In one embodiment with a single circumferential slit 1376a the cam includes a finger or tab that presses against the outer surface of arm 1384a. In one embodiment with multiple circumferential slits 1376a,b,c, . . . the cam includes multiple fingers or tabs that press against outer surfaces of multiple arms 1384a,b,c, . . . . In one embodiment multiple levers 1366a,b,c, . . . are used with their pads 1386a,b,c, . . . pinching the EMD 1388 at multiple locations longitudinally. In one embodiment contact of the EMD 1388 occurs between the pad 1386a of a single lever 1366a along the length of the collet system.
Referring to
In one embodiment rotation of 20 degrees of outer housing 1363 relative to inner housing 1362 corresponds to an increment of rotation for engagement of a pad 1386a,b,c, . . . of corresponding lever 1366a,b,c, . . . with EMD 1388. In one embodiment rotation of less than 20 degrees of outer housing 1363 relative to inner housing 1362 corresponds to an increment of rotation for engagement of a pad 1386a,b,c, . . . of corresponding lever 1366a,b,c, . . . with EMD 1388. In one embodiment rotation of more than 20 degrees of outer housing 1363 relative to inner housing 1362 corresponds to an increment of rotation for engagement of a pad 1386a,b,c, . . . of corresponding lever 1366a,b,c, . . . with EMD 1388.
Referring to
Collet 1504 has a collet first member 1512 that has a first engagement portion 1514. Collet 1504 has a collet second member 1516 that is driven.
Collet engagement member 1506 has a second engagement portion 1518.
Collet first member 1512 and collet engagement member 1506 move between an engaged position and a disengaged position. Referring to
First engagement portion 1514 engages second engagement portion 1518 as collet first member 1512 and collet engagement member 1506 are moved to the engaged position. Referring to
Rotation of collet first member 1512 with respect to collet second member 1516 in a first direction 1520 in the engaged position pinches an EMD 1502 within the collet 1504 and rotation of collet first member 1512 with respect to collet second member 1516 in a second direction 1522 opposite the first direction 1520 unpinches the EMD 1502 within the collet 1504.
In collet-drive system 1500 the first engagement portion 1514 includes a plurality of splines that extend circumferentially about at least a portion of the collet first member 1512. The second engagement portion 1518 includes a plurality of members operatively engaging the plurality of splines of the first engagement portion 1514.
In one embodiment collet second member 1516 is connected to a bevel gear 1524 that meshes with and is driven by a capstan bevel gear 1526. In one embodiment collet second member 1516 is driven by a coupler.
In one embodiment the plurality of splines of first engagement portion 1514 includes external spline teeth that extend longitudinally. In one embodiment the plurality of members of second engagement portion 1518 includes internal spline teeth that extend longitudinally and mesh with the external spline teeth that extend longitudinally of the plurality of splines of first engagement portion 1514.
Collet engagement member 1506 is integrally connected to first drive module 1508 and oriented such that its centerline is aligned longitudinally with the axis of EMD 1502.
First drive module 1508 and second drive module 1510 translate longitudinally relative to a fixed lead screw 1528 (illustrated as reference 76 in
Referring to
In one embodiment translation of first drive module 1508 is accomplished as follows. A drive shaft of first actuator 1530 is integrally connected to a first actuation pulley 1534 that drives a first belt 1536 that drives a first nut pulley 1538 that is integrally connected to a first nut-bearing assembly 1540 that meshes with lead screw 1528 and is integrally connected to first drive module 1508. Similarly, in one embodiment translation of second drive module 1510 is accomplished as follows. A drive shaft of second actuator 1532 is integrally connected to a second actuation pulley 1544 that drives a second belt 1546 that drives a second nut pulley 1548 that is integrally connected to a second nut-bearing assembly 1550 that meshes with lead screw 1528 and is integrally connected to second drive module 1510.
First drive module 1508 includes a clamp and rotational drive mechanism that acts both to clamp/unclamp an EMD as well as to translate the EMD along its longitudinal axis. In one embodiment the clamp and rotational drive mechanism includes drive tire 1558 and an idler tire 1568. In one embodiment drive tire 1558 is driven as follows. A driver gear 1552 meshes with a drive tire gear 1554 that is integrally connected to a drive tire capstan 1556 that is integrally connected to drive tire 1558. It is contemplated that other clamp and translational devices known in the art may be employed as well.
Referring to
In one embodiment rotation of driver gear 1552 is accomplished as follows. A drive shaft of third actuator 1560 is integrally connected to a third actuation pulley 1562 (supported by a bearing) that drives a second belt 1564 that drives a driver gear pulley 1566 (supported by a bearing) that is integrally connected to driver gear 1552.
First drive module 1508 includes a straddle rocker 1570 and a spring 1572. Straddle rocker 1570 rotates about a pivot 1574 that is parallel to the axis of drive tire 1558 and idler tire 1568. Spring 1572 is a tension spring with one end connected to a rocker distal post 1575 integrally connected to straddle rocker 1570 and one end connected to a driver gear extension post 1576 that extends from driver gear 1552. Straddle rocker 1570 is a spring-loaded bell crank, that is, a spring-loaded lever with two arms and pivot 1574. One arm of straddle rocker 1570 is integrally connected to rocker distal post 1575 at its free end. One arm of straddle rocker 1570 supports idler tire 1568 at its free end.
Second drive module 1510 includes driven capstan bevel gear 1526 and capstan 1527. Capstan bevel gear 1526 is integrally connected to capstan 1527 that is driven by an actuator (not shown). Second drive module 1510 is integrally connected to an extension link 1578 that extends out from the far end (that is, end farthest from lead screw 1528) of second drive module 1510 in a direction toward first drive module 1508 and parallel to lead screw 1528 and to EMD 1502. In one embodiment extension link 1578 is a rectangular bar with its length greater than its width and its width greater than its height (thickness). Extension link 1578 includes a first lip 1580 and a second lip 1581. In one embodiment first lip 1580 and second lip 1581 are rectangular bar projections, like flanges, oriented up and perpendicular to extension link 1578. In one embodiment first lip 1580 is located at the proximal end of extension link 1578 and second lip 1581 is located near the proximal end of extension link 1578 such that there is a gap between the inside faces of first lip 1580 and second lip 1581.
In one embodiment collet-drive system 1500 includes a cassette (not shown) that includes collet 1504, collet engagement member 1506, drive tire 1558, and idler tire 1568.
Operation of collet-drive system 1500 consists of multiple states, as described herein.
Referring to
Referring to
Referring to
In the exchange state collet 1504 unpinches EMD 1502 by rotation of capstan bevel gear 1526 that meshes and rotates driven bevel gear 1524 that rotates collet second member 1516 relative to collet first member 1512. Note that collet first member 1512 is locked (does not move) due to engagement of spline teeth of first engagement portion 1514 with spline teeth of second engagement portion 1518 that does not move. With collet 1504 in an unpinched state EMD 1502 can be removed. In one embodiment EMD 1502 can be removed by side or radial unloading with alignment of a collet slit 1582 in collet 1504 and a collet engagement member slit 1584 in collet engagement member 1506. In one embodiment EMD 1502 can be removed by axial unloading.
Referring to
Referring to
Referring to
In the tire driving state collet 1504 unpinches EMD 1502 by rotation of capstan bevel gear 1526 that meshes and rotates driven bevel gear 1524 that rotates collet second member 1516 relative to collet first member 1512. Note that collet first member 1512 is locked (does not move) due to engagement of spline teeth of first engagement portion 1514 with spline teeth of second engagement portion 1518 that does not move. With collet 1504 in an unpinched state EMD 1502 can be translated by rotation of drive tire 1558 gripping EMD 1502 against idler tire 1568.
Collet drive system 1500 operates in a reset mode or in an exchange mode. In the reset mode the sequence for operation is driving state (first state), collet lock state (second state), collet pinched-tire grip state (third state), tire driving state (fourth state), collet pinched-tire grip state (third state), collet lock state (second state), and back to driving state (first state). In the exchange mode the sequence of operation is driving state (first state), collet lock state (second state), device exchange state (second alternate state), collet lock state (second state), and back to driving state (first state).
Collet-drive system 1500 incorporates a collet 1504. To minimize the amount of actuation required collet-drive system 1500 is designed to lock half of collet 1504, preventing rotational motion of this half, while providing a rotational degree of freedom to half of collet 1504 for unpinching and pinching of EMD 1502. There are multiple ways to lock half of collet 1504. The term lock refers to maintaining a component stationary and fixed relative to the patient. If the component is stationary relative to the patient bed rail then for the purposes herein the component is stationary and fixed relative to the patient. One embodiment includes engaging splines. One embodiment includes inserting a locking pin in a hole. One embodiment includes inserting a key in a keyway. One embodiment includes means for mechanical interference that prevent rotation.
In one embodiment, EMD 1502 is unpinched and then after EMD is unpinched, the various components are moved to a homing position to allow for removal of the EMD from the device through aligned slots.
Referring to
Drive module 1612 translates longitudinally relative to a fixed lead screw 1614 (identified as reference 76 in
Referring to
In one embodiment translation of drive module 1612 is accomplished as described for the drive modules of
Referring to
EMD support 1606 is a constraint preventing EMD 1602 from buckling as EMD 1602 is advanced distally. In one embodiment EMD support 1606 is a system of telescoping sections with inner diameters larger than the diameter of EMD 1602. In one embodiment EMD support 1606 is a track that allows the device to be radially loaded. In one embodiment EMD support 1606 is a tube. In one embodiment EMD support 1606 is any system that prevents EMD 1602 from buckling or bending when advancing.
Referring to
Referring to
Referring to
COLLETS: A number of collet designs are provided herein that may be used in the robotic systems described. Referring to
Referring to
First section 806 has a longitudinal slit 812 extending from an outer surface of the first section and terminating at a radial center of the inner member 802. Second tapered section 808 has a longitudinal slit 814 extending through the entire second section 808 from a portion of the outer surface of the second section in line with the slit 812 in the first section 806 to a portion of the outer surface of the second section 180 degrees from the first outer surface region. The second slit 814 defines a first plane and a second plane at an angle to the first plane. In one embodiment slit the walls of slit 812 are parallel and the walls of slit 814 are nonparallel. In one embodiment the walls of slit 812 and slit 814 are parallel. In one embodiment the walls of slit 812 and slit 814 are nonparallel.
Referring to
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Referring to
Referring to
Referring to
In operation, translational movement of the inner member 802 into the tapered cavity 816 of outer member 804 forces the two portions 818 and 820 of the second section or portion 808 to move toward each other thereby causing the two facing surfaces 819 and 821 of portions 818 and 820, respectively, to move toward each other to pinch the EMD. As inner member 802 moves distally into outer member 804 compressive forces due to contact between inner member 802 and outer member 804 (that occur between the inner circumferential surface of the tapered cavity 816 and the outer circumferential surface of the distal end of inner second section 808) act on the two sections of inner member second section 808. These forces overcome the inherent compliance of the two sections of inner member second section 808 resulting in the two facing surfaces 819 and 821 of portions 818 and 820, respectively, moving toward one another in a loaded configuration.
In one embodiment in the loading configuration the inner surfaces 819 and 821 of the second section 808 of inner member 802 contact the EMD first at the distal free end 810 and then progressively continue to contact the EMD proximally in the slit 814 of inner member tapered second section 808.
To move inner member 802 into outer member 804 requires an external driving force in the distal direction applied to inner member 802 from an operator or robotic system (not shown). In one embodiment the external driving force in the distal direction is applied to the proximal end of inner member 802. In one embodiment inner member is moved relative to outer member by rotating one of the inner member 802 and outer member 804 with a rotational input that engages a screw member to translate the inner member 802 relative to outer member 804 linearly along the longitudinal axes of the collet.
To increasingly move inner member 802 distally into outer member 804 requires an increasing external driving force to overcome the increasing compliance force (to increasingly move the two facing surfaces 819 and 821 of portions 818 and 820, respectively, to move toward one another) and to overcome the increasing friction force (as a result of increasing contact between the inner circumferential surface of the tapered cavity 816 and the outer circumferential surface of the distal end of second section 808).
The loaded configuration becomes a locked configuration when the two facing surfaces 819 and 821 of portions 818 and 820, respectively, pinch down on the EMD such that the EMD cannot move. In the locked configuration no external driving force is needed. Friction forces (due to contact between the inner circumferential surface of the tapered cavity 816 and the outer circumferential surface of the distal end of second section 808) maintain the collet 800 in the locked configuration. In other words, in the locked configuration inner member 802 is locked with outer member 804 due to friction.
In operation, translational movement of the inner member 802 away from the tapered cavity 816 of outer member 804, that is when inner member 802 is withdrawn with respect to outer member 804, separates the two portions 818 and 820 of the second section or portion 808 from one another thereby causing the two facing surfaces 819 and 821 of portions 818 and 820, respectively, to move away from one another to unpinch the EMD. When inner member 802 is withdrawn from outer member 804 the inherent compliance of the two sections of inner member second section 808 restores the two facing surfaces 819 and 821 of portions 818 and 820, respectively, to their normally opened unloaded configuration.
To move inner member 802 away from outer member 804 requires an external driving force in the proximal direction applied to inner member 802 from an operator or robotic system (not shown). The external driving force in the proximal direction must overcome the friction force keeping the collet mechanism 800 in the locked configuration. In one embodiment the external driving force is applied to the proximal end of inner member 802.
In one embodiment the two sections of inner member second section 808 are connected by a living hinge with spring properties that force the two sections away from one another as the inner member is moved toward the open end of the outer member. In one embodiment a separate spring operates to bias the two sections apart.
In one embodiment the outer surface of inner member tapered second section 808 has smooth walls. In one embodiment the outer surface of inner member tapered second section 808 has walls that are not smooth, for example, one or more concave pockets or wells appear on the outer surface. Designs with non-smooth walls allow for nonuniform and generally lower inherent compliance of the two sections of inner member tapered second section 808 in comparison to designs with smooth walls.
In one embodiment the inner member 802 is made of a moldable plastic. In one embodiment the inner surfaces 819 and 821 of the second section 808 of inner member 802 include an elastomeric or other deformable or compliant material that deforms about the EMD during pinching and in the locked configuration.
In one embodiment an EMD is radially loaded through outer member slit 805 and inner member slit 812 and slit 814 when slits 805, 812, and 814 are aligned. The radial loading allows a user to place an EMD into the center of the collet without having to thread a free end of the EMD through a first end 823. Rather a portion of the EMD between a first end and a second end of the EMD is placed directly into the radial center of the collet through aligned slits 805, 812 and 814. In radial loading a first terminal end of the EMD remains distal the distal end of the collet and the second opposed terminal end of the EMD remains proximal the proximal end of the collet while the portion of the EMD intermediate first end and second end of the EMD is inserted through slits 805, 812, and 814 to the radial center of the collet. Loading an EMD described in this paragraph is referred to herein as side loading or radial loading.
Referring to
Referring to
In one embodiment first portion 818 and second portion of second section 808 defines two cantilevered portions that extend from inner member first section. Cantilevered portions 818 and 820 have a varying spring forces along their respective longitudinal length such that the surfaces 819 and 821 that contact the EMD positioned therebetween conform well to the EMD to keep pressure applied to the EMD low and spread out along the surfaces 819 and 821. The spring force applied to the EMD can be made to vary by changing the cross-sectional thickness of the cantilevered portions 818 and 820 along the longitudinal axis of collet 800
Collet 800 offers the feature of increased stiffness for greater release force with full slit 814 in second section 808 of inner member 802 and partial slit 812 in first section 806 in inner member 802.
Referring to
Referring to
Referring to
Referring to
In one embodiment the region of the inner member 836 proximate the bottom of slit 830 is a living hinge with spring properties that force the two sections away from one another as the inner member is moved toward the open end of the outer member. In one embodiment a separate spring operates to bias the two sections 838 and 840 apart.
Friction forces (due to contact between the inner circumferential surface of the tapered cavity of outer member 804 and the outer circumferential surface of the distal end of second section 834) maintain the collet 826 in the locked configuration. In other words, in the locked configuration inner member 828 is locked with outer member 804 due to friction.
Based on the dimension and angle of longitudinal slit 830 that forms two sections, a first section 840 and a second section 842, of inner member 828, the collet accommodates a larger range of diameters of EMDs in comparison to the collet of
Referring to
Inner member 854 has a longitudinal slit 855 along its full length extending from an outer surface of the inner member and terminating at its radial center. Outer member 860 has a longitudinal slit 861 along its full length extending from an outer surface of the outer member and terminating at its radial center. In one embodiment slits 855 and 861 have parallel walls. In one embodiment slits 855 and 861 have nonparallel walls, such as v-shaped walls with its vertex toward the radial center. In one embodiment slits 855 and 861 have lead-in chamfers at the outer surface. In one embodiment slits 855 and 861 have no chamfers at the outer surface.
Referring to
Transition from an unpinched to a pinched configuration or from a pinched to an unpinched configuration requires a user or a drive system to impose relative angular motion between inner member 854 and outer member 860 about the longitudinal axis. In one embodiment rotation of inner member 854 relative to outer member 860 of 90 degrees about the longitudinal axis corresponds to the transition from unpinched to pinched configurations. In one embodiment rotation of inner member 854 relative to outer member 860 of 180 degrees about the longitudinal axis corresponds to the transition from unpinched to pinched configurations. In one embodiment rotation of inner member 854 relative to outer member 860 of an arbitrary value less than 360 degrees about the longitudinal axis corresponds to the transition from unpinched to pinched configurations.
In one embodiment the internal cam 865 is designed to achieve pinching in a clockwise rotation of outer member 860 relative to inner member 854 about the longitudinal axis. In one embodiment the cam is designed to achieve pinching in a counterclockwise rotation of outer member 860 relative to inner member 854 about the longitudinal axis.
In one embodiment the internal cam 865 achieves pinching at a single position in the rotation of inner member 854 relative to outer member 860 about the longitudinal axis. In one embodiment the cam achieves pinching at two or more positions in the rotation of inner member 854 relative to outer member 860 about the longitudinal axis.
In one embodiment the internal cam 865 is designed with a dwell such that relative rotation between inner member 854 and outer member 860 does not result in a change of state, that is, if the collet system 852 is in a pinched configuration it remains in a pinched configuration or if the collet system 852 is in an unpinched configuration it remains in an unpinched configuration. The dwell is achieved by having no change in the radial dimension of the profile of the internal cam 865 over a range of relative rotation between inner member 854 and outer member 860. In one embodiment in a pinched configuration a dwell accommodates for possible errors in the displacement commands to the motors rotationally driving the inner member 854 and the outer member 860 giving some tolerance to errors with the EMD 867 remaining pinched.
In one embodiment cam 865 is designed such that rotation of inner member 854 relative to outer member 860 of 90 degrees about the longitudinal axis maintains the EMD in the pinched configuration. In one embodiment the cam is designed such that rotation of inner member 854 relative to outer member 860 of less than 90 degrees about the longitudinal axis maintains the EMD in the pinched configuration. In one embodiment the cam is designed such that rotation of inner member 854 relative to outer member 860 of more than 90 degrees about the longitudinal axis maintains the EMD in the pinched configuration.
In one embodiment cam 865 is designed such that rotation of inner member 854 relative to outer member 860 of 90 degrees about the longitudinal axis maintains the EMD in the unpinched configuration. In one embodiment the cam is designed such that rotation of inner member 854 relative to outer member 860 of less than 90 degrees about the longitudinal axis maintains the EMD in the unpinched configuration. In one embodiment the cam is designed such that rotation of inner member 854 relative to outer member 860 of more than 90 degrees about the longitudinal axis maintains the EMD in the unpinched configuration.
In the assembled collet 852 key 859 of inner member 854 is retained in channel 863 of outer member 860 allowing for freedom of rotation of inner member 854 relative to outer member 860 and no freedom of translation of rotation of inner member 854 relative to outer member 860. Key 859 captured in channel 863 ensures that inner member 854 and outer member 860 are aligned during assembly such that outer surface of pad 856 of follower finger 858 is positioned longitudinally opposite surface 857 in inner member 854. Key 859 captured in channel 863 prevents both members from being pulled apart when in a pinched or unpinched configuration.
In an initial configuration slit 855 in inner member 854 of collet 852 is aligned with slit 861 in outer member 860 to allow for side or radial loading of EMD as described herein.
Referring to
Inner member 870 has a longitudinal slit 871 along its full length extending from an outer surface of the inner member and terminating at its radial center. Outer member 876 has a longitudinal slit 877 along its full length extending from an outer surface of the outer member and terminating at its radial center. In one embodiment slits 871 and 877 have parallel walls. In one embodiment slits 871 and 877 have nonparallel walls, such as v-shaped walls with its vertex toward the radial center. In one embodiment slits 871 and 877 have lead-in chamfers at the outer surface. In one embodiment slits 871 and 877 have no chamfers at the outer surface.
Referring to
Referring to
Outer member 876 is a single integrated member comprised of two portions with a longitudinal slit 877 from its external surface to its radial center. Starting most proximally a first portion 896 is a cylindrical cup section with internal threads 892 at its proximal portion and internal cylindrical cavity at its distal portion. Internal threads 892 mesh with external threads 890 of inner member 870. The cylindrical cavity at the distal portion of first portion 896 receives collar 874. A second portion 898 of outer member 876 is a cylindrical section with an internal lumen at its radial center.
Referring to
Collar 874 has a longitudinal slit 894 through the collar circumferential wall with a radial slit to its center. In one embodiment slit 894 has parallel walls. In one embodiment slit 894 has nonparallel walls, such as v-shaped walls with its vertex toward the radial center. In one embodiment slit 894 has a lead-in chamfer at the outer surface. In one embodiment slit 894 has no chamfer at the outer surface.
In one embodiment collar 874 is located in the distal portion of the internal cavity of outer member 876 by extension 888 of inner member 870. Extension 888 serves as a mechanical key to ensure that collar 874 rotates with inner member 870 such that the ends of flexure 872 can be squeezed together longitudinally and not be exposed to relative rotation or torque. In other words, the ends of flexure 872 can translate relative to each other and do not rotate relative to each other. Extension 888 is constrained rotationally by a pocket 875 in collar 874 that acts a keyway and is free to translate longitudinally as inner member 870 is rotated relative to outer member 868.
Referring to
In operation pinching EMD 878 is achieved by rotating inner member 870 relative to outer member 876 in a direction about a longitudinal axis that screws together external threads 892 and internal threads 892. As a result, flexure 872 can be made to flex or bend (such that it has a smaller radius of curvature) and an outer surface 873 of flexure 872 (at and near the longitudinal center of the flexure) can be used to pinch EMD 878 against inner surface 880 of inner member 870. The longitudinal distance between the two ends of flexure 872 is determined by rotation of inner member 870 relative to outer member 876 and can be used to vary the amount of flex. As the longitudinal distance between the ends of flexure 872 decreases, the flex or bend of the flexure increases giving the flexure a smaller radius of curvature and a larger lateral distance, defined as the distance perpendicular to the longitudinal axis at the longitudinal center of the flexure between the outer surface 873 of the unflexed flexure 872 and the outer surface 873 of the flexed flexure 872. Since the lateral distance is constrained by the internal cavity, EMD 878 is trapped between outer surface 873 of flexure 872 and internal surface 880 of inner member 870.
In operation unpinching EMD 878 is achieved by rotating inner member 870 relative to outer member 876 in a direction about a longitudinal axis that unscrews external threads 892 and internal threads 892. As a result, flexure 872 can be made to unflex or unbend (such that it has a larger radius of curvature) and outer surface 873 of flexure 872 unpinches EMD 878 from inner surface 880 of inner member 870. The longitudinal distance between the two ends of flexure 872 is determined by rotation of inner member 870 relative to outer member 876 and can be used to vary the amount of flex. As the longitudinal distance between the ends of flexure 872 increases, the flex or bend of the flexure decreases giving the flexure a larger radius of curvature and a smaller lateral distance, defined as the distance perpendicular to the longitudinal axis at the longitudinal center of the flexure between the outer surface 873 of the unflexed flexure 872 and the outer surface 873 of the flexed flexure 872. In the unpinched configuration the lateral distance between the outer surface 873 of flexure 872 and internal surface 880 of inner member 870 is larger than the diameter of EMD 878 such that EMD 878 is free.
In one embodiment the internal surface 880 of inner member 870 that receives flexure 872 in capturing EMD 878 in the pinched configuration is concave, for example, having a similar profile to the profile of the outer surface 873 of flexed flexure 872. This would increase the surface area contacting EMD 878 and can increase the resistive torque on EMD 878 by moving it away from the central axis of rotation. In one embodiment the internal surface 880 of inner member 870 that receives flexure 872 in capturing EMD 878 in the pinched configuration is flat.
In one embodiment inner member 870 is made of one material, for example, moldable plastic. In one embodiment inner member 870 is made of more than one material. For example, in one embodiment the internal surface 880 of inner member 870 that receives flexure 872 in capturing EMD 878 in the pinched configuration has an elastomeric lining or coating on a moldable plastic inner member 870.
In one embodiment flexure 872 is made of one material, for example, moldable plastic. In one embodiment flexure 872 is made of more than one material. For example, in one embodiment flexure 872 has an elastomeric lining or coating on a moldable plastic inner portion.
In one embodiment of collet 868 a single flexure 872 is used. In one embodiment of collet 868 more than one flexure 872 is used. For example, two flexures oriented 180 degrees apart around the central longitudinal axis could be used to pinch and unpinch EMD 878 based on relative rotation of inner member 870 and outer member 876 using the principle described herein.
In an initial configuration slit 871 in inner member 870 of collet 868 is aligned with slit 877 in outer member 876 to allow for side or radial loading of EMD as described herein.
Referring to
Referring to
Referring to
The first drive block assembly 1170 includes a first spur gear 1174, a first spur gear pin 1176, and a first drive block retainer 1178. In one embodiment the first spur gear 1174 rotates about the first spur gear pin 1176 that is held into side walls of the first drive block retainer 1178. In one embodiment the first spur gear 1174 is integrally connected to the first spur gear pin 1176 in the middle of its length, and the ends of the first spur gear pin 1176 on either side of the first spur gear 1174 are supported in holes that act as rotational bearings in the outer walls of the first drive block retainer 1178. In one embodiment the first spur gear 1174 is integrally connected to the first spur gear pin 1176 in the middle of its length, and the ends of the first spur gear pin 1176 on either side of the first spur gear 1174 are supported by rotational bearings that are mounted in the outer walls of the first drive block retainer 1178. In one embodiment the first drive block retainer 1178 includes a first drive block cutout 1180 that exposes a section of first spur gear teeth 1182 of the first spur gear 1174. In one embodiment the first drive block cutout 1180 has a semicircular convex cross-section in a plane transverse to the longitudinal axis.
The second drive block assembly 1172 includes a second spur gear 1184, a second spur gear pin 1186, and a second drive block retainer 1188. In one embodiment the second spur gear 1184 rotates about the second spur gear pin 1186 that is held into side walls of the second drive block retainer 1188. In one embodiment the second spur gear 1184 is integrally connected to the second spur gear pin 1186 in the middle of its length, and the ends of the second spur gear pin 1186 on either side of the second spur gear 1184 are supported in holes that act as rotational bearings in the outer walls of the second drive block retainer 1188. In one embodiment the second spur gear 1184 is integrally connected to the second spur gear pin 1186 in the middle of its length, and the ends of the second spur gear pin 1186 on either side of the second spur gear 1184 are supported by rotational bearings that are mounted in the outer walls of the second drive block retainer 1188. In one embodiment the second drive block retainer 1188 includes a second drive block cutout 1190 that exposes a section of second spur gear teeth 1192 of the second spur gear 1184. In one embodiment the second drive block cutout 1190 has a semicircular convex cross-section in a plane transverse to the longitudinal axis.
The first spur gear 1174 is driven by a first spur gear drive system (not shown) that can rotate the first spur gear 1174 in the clockwise direction or in the counterclockwise direction or not rotate the first spur gear 1174. The second spur gear 1184 is driven by a second spur gear drive system (not shown) that can rotate the second spur gear 1184 in the clockwise direction or in the counterclockwise direction or not rotate the second spur gear 1184. In one embodiment the first spur gear drive system, the second spur gear drive system, and the translational drive system are included in a combined translational-rotational drive system (not shown) that can rotate the first spur gear 1174, rotate the second spur gear 1184, and translate the drive block set 1156 simultaneously. In one embodiment the first spur gear drive system, the second spur gear drive system, and the translational drive system are included in a combined translational-rotational drive system (not shown) that can rotate the first spur gear 1174, rotate the second spur gear 1184, and translate the drive block set 1156 in sequence.
Referring to
In one embodiment the device retainer 1152 includes a distal drive collar 1196 and a proximal drive collar 1198. The distal drive collar 1196 is located distal to the geared section 1194 and proximal to the distal constant section 1164. The proximal drive collar 1198 is located proximal to the geared section 1194 and distal to the flexible bellows 1160. The distal drive collar 1196 and the proximal drive collar 1198 are longitudinal sections with flanges or lips that extend outward from the device retainer 1152. In one embodiment the device retainer 1152 includes a first intermediate constant section 1200 that is located distal to the flexible bellows 1160 and proximal to the proximal drive collar 1198.
Referring to
Referring to
Referring to
The drive block set 1156 includes a drive block open-close actuation system (not shown) that moves the first drive block assembly 1170 and the second drive block assembly 1172 toward and away from the device retainer 1152 in a direction transverse to the longitudinal axis. Referring to
Referring to
In one embodiment the first holding block 1212 includes a first holding block cutout 1216 and the second holding block 1214 includes a second holding block cutout 1218. In one embodiment the first holding block cutout 1216 and the second holding block 1214 each have a semicircular convex cross-section in a plane transverse to the longitudinal axis.
In one embodiment the device retainer 1152 includes a distal holding collar 1220 and a proximal holding collar 1222. The distal holding collar 1220 is located proximal to the flexible bellows 1160 and distal to a constant holding section 1224, which is a longitudinal section of the device retainer 1152 with a constant cross-section transverse to the longitudinal direction. The proximal holding collar 1222 is located distal to the proximal constant section 1166 and distal to the constant holding section 1224. The distal holding collar 1220 and a proximal holding collar 1222 are longitudinal sections with flanges or lips that extend outward from the device retainer 1152. In one embodiment the device retainer 1152 includes a second intermediate constant section 1226 that is located proximal to the flexible bellows 1160 and distal to the distal holding collar 1220. Device retainer 1152 serves as anti-buckling support allowing the collet to have a longer throw than the device buckling distance.
Referring to
Referring to
The holding block set 1158 includes a holding block actuation system (not shown) that moves the first holding block 1212 and the second holding block 1214 toward and away from the device retainer 1152 in a direction transverse to the longitudinal axis. Referring to
Referring to
Referring to
Referring to
Referring to
In one embodiment a rotational drive system (not shown) rotates (clockwise and counterclockwise) the compression collet system 1240 about the longitudinal axis 1250 of the EMD 1252. In one embodiment a translational drive system (not shown) translates (advances and retracts) the compression collet system 1240 along the longitudinal axis 1250 of the EMD 1252.
In one embodiment the compression collet system 1240 includes slits (not shown) to allow for side or radial loading of EMD 1252.
In one embodiment a collet may include a collet first member and a collet second member that when moved relative to one another pinch and unpinch an EMD. In one embodiment the collet first member and the collet second member may be formed as a single component in which the collet first member and collet second member are compliantly connected. In one non-limiting example collet first member and collet second member may be connected with a living hinge, accordion portion of flexible portions that are movable relative to each other
Referring to
Referring to
The reset position is automatically determined as a function of one or more of input device instructions, the offset distance of the two tire assemblies and position of the EMD.
In one embodiment control system provides the reset instructions when the second position reaches a predetermined distance from the first position. Referring to
When an operator through a user input provides instructions to rotate EMD 208 about its longitudinal axis in a first direction first tire assembly 222 and second tire assembly 224 move along their longitudinal axes in opposite directions until the EMD 208 reaches a second position 372 on first tire assembly 222 and a third position 375 of second tire assembly 224. The controller will automatically reset first tire assembly 222 and second tire assembly 224 along their respective longitudinal axes 242, 246 to a reset position. If the user continues to provide instructions to rotate EMD 208 in the same first direction as or after the first tire assembly and second tire assembly reaches or reached the second and third positions respectively, the controller will automatically set the reset position to a third location 374 on the first tire assembly and a second position 372 on the second tire assembly. In this manner tire assemblies 222 and 224 are in the position to continue rotating EMD 208 in the first direction for a greater number of rotations than if the reset position was the center positions 370 and 371. Stated another way the first tire assembly 222 and second tire assembly mover relative to one another along their respective longitudinal axes 242 and 246 between a first extended position illustrated in
In one embodiment the reset position is a function of the input device instructions including a duration of inactivity of the input device. Controller detects the duration of time that no instruction has been given to rotate the EMD. Once that duration reaches a predetermined time interval, the system automatically resets the first tire assembly 222 and second tire assembly 224 to an inactivity reset position. In one embodiment the inactivity reset position is a central position where the center portion of first tire assembly 222 is proximate the center portion of second tire assembly 224 such that first position 370 of the first tire assembly 222 is adjacent first position 371 of the second tire assembly 224. However, other inactivity reset positions may be used.
Referring to
Coupler mechanism 218 includes a first support 268 and a second support 280 that extend outwardly of base 212 via shaft 272 and shaft 282 respectively. EMD engagement mechanism 216 includes a first tire assembly 222 and a second tire assembly 224. Tire assemblies 222 and 224 are located within a housing 220 that is operatively connected to base 212. EMD engagement mechanism 216 includes a first tire assembly 222 and a second tire assembly 224. In one embodiment first tire assembly 222 and second tire assembly 224 are identical. First tire assembly 222 includes a hub 226 supporting a tire 228 that is positioned about an external surface of hub 226. Similarly, second tire assembly 224 includes a hub 227 supporting a tire 229 that is positioned about an external surface of hub 227. Each tire 228 and 229 include a roller having a longitudinal axis about which the tire rotates. Tire 228 has an outer surface that contacts the EMD. In one embodiment the outer surface of each tire has a constant radius from a first end of the tire to the opposing second end of the tire. In one embodiment the radius of the outer surface varies along the longitudinal axis of the tire. In one embodiment the radius of the outer surface intermediate the two ends of the tire is greater than the radius of the outer center at the each of the two ends of the tire. In one embodiment the outer surface defines a prolate shape. In one embodiment the outer surface of the tires define a frusto conical shape or profile in which tires have a larger diameter proximate one free end of the tire than the other end of the tire. When the first tire and second tire grip an EMD therebetween the surfaces pressing against the EMD are substantially parallel to one another, while the surfaces of the tires that are not pressing against the EMD are not parallel. Referring to
Movement of tires 228 and 229 toward and away from each other grip and ungrip an EMD placed therebetween. As described herein movement of tires 228 and 229 about their longitudinal axis translates the EMD gripped therebetween and relative movement of tires 228 and 229 along the longitudinal axis of tires 228 and 229 rotate the gripped EMD about its longitudinal axis.
In one embodiment hub 226 includes a first portion 230 having an outer cylindrical shape and a second portion 232 having a frustoconical shape extending from the first portion 230 and terminating at a top end 234. A pair of engagement arms 236 extend from a bottom of first portion 230 and terminate with a hook barb shaped member 238 that operatively engages a portion of second support 268.
Referring to
A first motor 240 is operatively coupled to first tire assembly 222 providing rotational movement to first tire assembly 222 and therefore also tire 228 about a longitudinal axis 242 of first tire assembly 222. Control of first motor 240 from the workstation provides control of the linear movement of the EMD. In one embodiment, first motor 240 has an output shaft 290 operatively coupled to a first pulley 292. First pulley rotates with output shaft 290 and rotates a second pulley 270 via a belt 294. In one embodiment pulley 292 and 270 are gears that are connected either directly via gear teeth or through a gear chain having at least one additional gear connecting gear 292 and 270. In one embodiment, output shaft 290 is directly connected to shaft 272 or to tire assembly 222 with a coupler.
Referring to
Referring to
Referring to
Referring to
Referring to
First housing coupler 266 includes a center region housing a pulley or gear 270 secured to a shaft 272 of first support 268. First support 268 includes a portion extending from shaft 272 away from housing coupler 266 having a first region 274 and a second frustoconical portion 276 respectively receiving portions 230 and 232 of first tire assembly 222. First region 274 has a diameter that is greater than the diameter of shaft portion 272. Referring to
A second support or coupler 280 includes a shaft portion 282, a conical support region 284, a frustoconical portion 286 and a shelf region 279. Shelf region 279 extends from shaft portion 282 a distance equal to difference between the radius of the first region 284 and the radius of the shaft portion 282. As described herein barbs 239 removably engage shelf region 278 to removably secure second tire assembly 224 from second support 280. Shaft 282 is free to rotate about longitudinal axis 246 within a second housing coupler 288 in response to rotation of the output shaft of first motor 240. As discussed in further detail herein, in one embodiment installation and/or removal of first tire assembly 222 and second tire assembly 224 is accomplished via automated process controlled by the controller.
In one embodiment first motor 240 is operatively secured to first housing coupler 266 such that first motor 240 moves along with first housing coupler 266. In one embodiment output shaft 290 of first motor 240 includes a key shape that engages pulley 292 such that pulley 292 moves with first housing coupler 266 while first motor 240 is fixed relative to base 212. In one embodiment first motor 240 and pulley 292 moves in direction parallel to the longitudinal axis of shaft 272 with first housing coupler 266.
Referring to
Referring to
Referring to
In one embodiment a drive module includes a first actuator operatively rotating a first shaft and/or a second shaft. A second actuator operatively translates the first shaft along its longitudinal axis relative to the second shaft from a first position to a second position. A first tire assembly is removably attached to the first shaft and a second tire assembly removably attached to a second shaft. An EMD having a longitudinal axis being positioned at a first location between the first tire assembly and the second tire assembly, wherein rotation of the first shaft translates an EMD along its longitudinal axis between the first tire assembly and the second tire assembly; and rotation of the second shaft rotates the EMD about its longitudinal axis. A third actuator operatively moves the first tire assembly toward and away from the second tire assembly gripping and ungripping the EMD from between the first tire assembly and the second tire assembly. A holding clamp releasably clamps a portion of the EMD spaced from the first tire and the second tire along the longitudinal axis of the EMD. In one embodiment the third actuator automatically moves the first shaft away from the second shaft and the second actuator automatically moves the first shaft back to a reset position when the first shaft reaches a predetermined distance from the first position, and the holding clamp automatically clamps the EMD while the first shaft is moved away from the second shaft. In one embodiment the third actuator operatively moves the clamp between a clamping position to an unclamped position.
In one embodiment drive mechanism operates in at least three different modes. In a drive mode the clamp is an unclamped position with respect to the EMD and the first tire assembly and second tire assembly grip the EMD therebetween. In a reset mode, the clamp is in a clamped position with respect to the EMD and first tire assembly being is in an ungripped position. In an exchange mode, the clamp is in the unclamped position and the tire engagement mechanism being in an the ungripped position.
Referring to
In the reset mode, prior to ungripping the EMD from between the first tire and the second tire the clamp is moved the clamped position, so the EMD is secured from movement at two locations. Stated another way a first portion of the EMD is secured from rotation and linear movement at the clamp and a second portion of the EMD is secured from rotation and linear movement between the gripped first tire and second tire. After the clamp is moved to the clamped position, the first tire and/or second tire is moved to the ungripped position. By following this sequence of first clamping and then ungripping any force or torque in the EMD does not recoil resulting in loss of positional control of the EMD such as movement of the EMD within the drive and/or proximal portion. It is desirable to maintain the existing torque in the EMD while resetting to continue rotation of the EMD. The EMD acts like a spring and failure to maintain the existing torque and/or force will result in the EMD springing back to a position once the torque and/or force is released. The reset mode allows the first tire and second tire to be repositioned to allow continued rotation of the EMD in the same direction. By way of example an EMD is initially placed located in the middle of the first tire and the middle of the second tire where the first tire and second tire are generally aligned in a neutral position. In the neutral position the center line of the first tire is in contact with the centerline of the second tire.
To rotate the EMD in a first direction about its longitudinal axis the first tire and second tire move in equal and opposite direction along their respective longitudinal axes. The first tire and second tire are able to continue moving in equal and opposite directions until the EMD is positioned at a terminal end of the first tire and a terminal end of the second tire. Any further movement of the tires relative to one another would result in the EMD being no longer between the first tire and second tire. To allow the tires to continue to rotate the EMD about its longitudinal axis in the first direction, the EMD is clamped and then released from between the tires and the tires move back to the neutral position. The amount of throw or distance that the wheels can move in equal and opposite directions is the distance between the neutral position and the terminal ends of the tires. When the throw falls below a predetermined amount the drive mechanism automatically resets to the neutral position or other predetermined position. In one embodiment a wire guide (Not shown) prohibits the EMD from moving from between the tires during rotation of the EMD. Wire guide also acts to trigger automatic reset of the tires if the EMD moves to the terminal edges of the tires. (Passive wire guide retains EMD between the Tire surface to maintain the EMD such a guidewire centered between the terminal ends of the tires during reset as well as to prohibit the EMD from falling off of the tires)
In one embodiment in the exchange mode there is no need to clamp the EMD prior to ungripping the tires to avoid recoil since the EMD will be removed from the drive mechanism.
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Movement of coupler 280 in the first direction is accomplished by control of second motor 244 by a controller. Attachment of first tire assembly 222 to first coupler 268 is accomplished in the same manner as attachment of second tire assembly 224 to second coupler 280. In one embodiment a single second motor 244 controls the movement of first coupler 268 and second coupler 280 along first longitudinal axis 242 and second longitudinal axis 246 respectively, such that movement of second coupler in the first direction, results in the first coupler moving in an equal distance in a second direction. In this embodiment, the tire assemblies are attached to their respective couplers one at a time. Stated another way the tire assemblies are attached in series such that there is a time lapse between the attachment between the one tire assembly and the other tire assembly.
In one embodiment second motor 244 includes two separate motors independently controlling the first coupler and second coupler respectively. In the embodiment in which there are two separate motors it is possible to attach first tire assembly 222 and second tire assembly 224 to their respective couplers simultaneously.
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Drive mechanism 210 includes one or more pairs of tires that grip an EMD between them. First tire 228 and second tire 229 of the pair of times are rotated to drive the EMD linearly and tires 228 and 229 are moved axially in opposite directions to drive the EMD in rotation. Drive mechanism 210 include an actuation assembly 214 that includes a number of integrated mechanisms to rotate the tires, translate the tires axially and to ungrip the tires. A rotation mechanism provides rotation of the tires by operatively coupling a first motor directly to the tire assembly directly or indirectly via a belt/gears. In one embodiment the rotation mechanism is mounted onto housing coupler 266 along a linear guide system which moves the tires and rotational motors vertically. The linear guide could include the housing coupler having a bushing riding on rods 258. However, other linear guides known in the art may be used. To move the first housing coupler 266 and second housing coupler 288 on the linear rails or shafts 362 and 364 respectively, there are connecting rods 260 and 356 pivotally secured to a rocker 252 mounted to an output shaft of second motor 244. To grip and ungrip the tires between tires 228 and 229 a third motor 248 operatively rotates an eccentric member 322 having an offset aperture 324 receiving one of the shafts of the first coupler and second coupler such that rotation of the bushing results in moving tires 228 and 229 away from one another. The tire assemblies 222 and 224 are located within housing 220 such as cassette that loosely holds the tire assemblies in place for assembly onto the actuation hardware supported by base 212. The cassette 220 acts as a sterile barrier to cover the components within the base in combination with a drape. In one embodiment cassette the sterile barrier is used without a drape. The tire assemblies are fully supported by the couplers which requires a rigid connection to the tires both axially and rotationally. The rigid connection enables both rotation of the tires and vertical motion to enable rotation of the EMD. The connection between the tires and hardware is releasable to enable removal of the cassette.
In one embodiment, the shafts 272 and 282 and corresponding tire assemblies 222 and 224 are nominally tilted in the unloaded state by approximately 0.5-1 degree towards each other along their longitudinal axes so that the portion of the shafts proximate the shoulder region of the shafts are closer than the portion of the shafts distal the shoulder region. The amount by which the shafts are tilted corresponds to the amount of deflection of the components and the clearance in bearings and bushings so that when the tires are in the gripped state and correspondingly loaded and, the rotational axes of the tires are substantially parallel. This ensures that small diameter (as low as 0.010″) of the elongate medical devices are well-gripped by the tires and that there are no clearances due to a lack of parallelism when loaded in the gripped state. In one embodiment the longitudinal axis of the bearings in first housing coupler 362 are tilted relative to the longitudinal axis of the bearings in second housing coupler 364 or stated another way the longitudinal axis of shafts 272 are not parallel to the longitudinal axis of shafts 282. In one embodiment the angle between the longitudinal axis of the bearings supporting shaft 272 and shaft 282 is greater than 0 degrees and less than 90 degrees. The tilt of shafts 272 and 282 are set by the location of relative angle of the longitudinal axes of bearings 362 and 364.
In one embodiment robotic drive system includes a first actuator 240 operatively rotating a first shaft 272 and/or a second shaft 282 and a second actuator 244 operatively translating the first shaft 272 along its longitudinal axis relative to the second shaft 282 from a first position to a second position. A first bearing having a first longitudinal axis that supports the first shaft 272 and a second bearing having a second longitudinal axis supports the second shaft 282; and the first longitudinal axis and the second longitudinal axis being non-parallel. A first tire assembly 222 is removably attached to the first shaft 272 and a second tire assembly 224 is removably attached to a second shaft 282. A third actuator 248 operatively moves the second tire assembly 224 toward and away from the first tire assembly 222 gripping and ungripping an EMD having a longitudinal axis from between the first tire assembly and the second tire assembly. In one embodiment first bearing is positioned within first housing coupler 266 and second bearing is positioned within second housing coupler 268. However, first bearing and second bearing may be positioned elsewhere. For example, second bearing may be the eccentric bearing assembly 322. In one embodiment the first longitudinal axis of the first bearing and the second longitudinal axis of the second bearing intersect forming an acute angle at an intersection point, wherein the first tire assembly and the second tire assembly are intermediate the intersection point and the first bearing and the second bearing.
In one embodiment molded in clips at the bottom of the tire assemblies clip under a lip on the coupler such as the shelf region 278. To deal with the tolerance stack up which will necessarily involve some amount of backlash, a spring-loaded plunger is be used at the top of the coupler will ensure the clips are always in tension. For releasing the tire assemblies, the rotation mechanism can be actuated, and the clips hit a lip designed to release them and force the tire off. Once one tire assembly is off, it will float up when the other tire is released. For the initial installation, restraint 332 is a shipping clip located within housing 220 is used to hold the tires down so that both tire assemblies can be snapped in but have them still be removable by the system.
In one embodiment, a robotic system includes a base 212 having a first actuator 240 and a cassette 220 housing that is removably connected to the base 212. A pair of tires 222, 224 are within the cassette 220. A robotic actuator moves first shaft 272 and 282 to operatively engage first tire 222 and second tire 224 on the first shaft 272 and second shaft 282 extending from the base 212 into cassette 220. In one embodiment the robotic actuator operatively disengages the pair of tires from the first shaft and/or second shaft. In one embodiment more than one pair of tires are positioned within cassette 220 and are operatively engaged and disengaged from respective shafts.
Rotation of the EMD occurs by moving tires 228 and 229 in opposite directions. Since the upward and downward movement of tires 228 and 229 is a fixed distance, in order to continue rotating the EMD in a same direction the tires need to be reset. Resetting the rotation capabilities of the tires includes incorporating a separate brake clamp that holds the EMD when tires 228 and 229 can be ungripped and then returned to the desired position after reset. The brake clamp includes a cam 298 with an engagement portion 300 and a clamp support 302.
Cam 298 is rotated by a motor that is controlled by the controller. In one embodiment the motor used to rotate cam 298 is the third motor 248 that is also used to grip and ungrip the tires from one another. In one embodiment motor 248 is operatively connected to both the brake mechanism and the grip/ungrip mechanism to coordinate the timing of the brake of the EMD and the grip/ungrip of the EMD from between the tires 228 and 229. As discussed herein first tire assembly via a first coupler 268 is mounted on an eccentric bushing 322 so that the first tire assembly can be swung away from the second tire assembly using rotation. The cam has a rocker arm that is linked to another rocker arm on the eccentric tire release by a tie rod. By linking these, as the cam is engaged with the clamp, the tires can be ungripped.
The drive 210 can be defined to have 3 distinct capabilities: driving, resetting, and exchanges. In the drive position, the cam is disengaged from the EMD and cam support and the follower 320 is riding free in the slot 316 so that the tires are gripped together by a spring force. In one embodiment a torsion spring (not shown) is operatively secured to the eccentric 322 and the base. In one embodiment a lever (not shown) is operatively coupled to the base with a linear spring in either compression or tension. Only rotational motion is used to grip and ungrip, accordingly, in one embodiment sealing between the base and the shafts is accomplished with a rotary shaft seal on the eccentric.
In the resetting position cam 298 fully clamps the EMD between the cam engagement portion 300 and the clamping pad 302 thus setting the brake before the follower 320 contacts the end of the slot 316. A dwell on the cam allows the cam to stay fully engaged clamping the EMD as the tires 228 and 229 are ungripped enough for reset. Tires are reset by activating second motor 244 moving the first tire assembly and second tire assembly to a position to continue rotation of the EMD in the desired direction.
In the exchange position cam 298 is positioned such that the cam is not clamping the EMD between the engagement portion and the cam support and the first and second tires are spaced from one another in the ungripped position. In this orientation the EMD is free to be removed from the drive mechanism 210.
In one embodiment a manual release is provided to release both the cam from locking the EMD and to ungrip tires 228 and 229. The manual release overrides the controller controlling the motors in the case of a power outage or other need to quickly release the EMD from the clamp and tires. In one embodiment, a portion of the cam is operatively connected to a handle accessible to a user to manipulate such as by twisting. This design feature could be a key sufficiently large to enable a user to grip the key with the user's hand, which is easy to grip. In one embodiment only the first tire assembly moves in an up and down direction, while the second tire assembly is in a fixed up down position. In this embodiment, the mechanism described above is retained, but one of the 2 tie rods that operatively secured to rocker 252 is removed. In this mode to obtain the same amount of EMD rotation, motor 244 turn twice as much as the embodiment in which both tie rods are connected.
Although the present disclosure has been described with reference to example embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the defined subject matter. For example, although different example embodiments may have been described as including one or more features providing one or more benefits, it is contemplated that the described features may be interchanged with one another or alternatively be combined with one another in the described example embodiments or in other alternative embodiments. The present disclosure described is manifestly intended to be as broad as possible. For example, unless specifically otherwise noted, the definitions reciting a single particular element also encompass a plurality of such particular elements.
This application claims the benefit of Provisional Application No. 62/874,173 (Atty Dkt C130-338) entitled MANIPULATION OF AN ELONGATED MEDICAL DEVICE and filed on Jul. 15, 2019.
Filing Document | Filing Date | Country | Kind |
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PCT/US20/41923 | 7/14/2020 | WO | 00 |
Number | Date | Country | |
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62874173 | Jul 2019 | US |