The present invention relates to surgical instruments and more particularly to surgical instruments which are remotely controlled by electronic control signals generated by a user which are sent to a drive unit which drives mechanically drivable components of a mechanical apparatus which support a surgical instrument.
In accordance with a first aspect of the present invention, a medical system is provided. The medical system comprises a rigid support configured for being affixed relative to a patient table. By way of non-limiting example, the rigid support may be a rigid post configured for being mounted to the patient table. The medical system further comprises a rigid template having a location element (e.g., a location ball). In one embodiment, the template comprises a right angle arm having a free end on which the location element is disposed.
The medical system further comprises a surgical instrument having a rigid guide tube and a surgical insert disposed within the guide tube. The surgical insert carries a distal tool configured for performing a medical procedure on a patient. In one embodiment, the surgical instrument further includes a carriage assembly on which the guide tube is mounted. In another embodiment, the surgical instrument is configured for linearly sliding and/or pivoting relative to the rigid support.
The medical system further comprises a clamp configured for alternately mounting the surgical instrument to the rigid support and the surgical instrument to the rigid support, such that the location element and guide tube both coincide with a target region on the patient (e.g., an intended incision point on the patient). In one embodiment, the location element laterally extends from the bracket the same distance as the guide tube laterally extends from the bracket.
In one embodiment, the medical system may further comprise a yoke and a pin configured for removably mounting the yoke to the rigid support, and the surgical instrument may further comprises a pivot piece configured for being pivotably secured to the yoke. In another embodiment, the medical system may further comprise a drive unit (e.g., one having a motor array) configured for moving the surgical instrument within at least one degree-of-freedom (e.g., an actuation of the distal tool, and/or a linear sliding of the surgical instrument relative to the rigid support, and/or a pivoting of the surgical instrument about the rigid support). This embodiment may further comprise a remote controller configured for directing the drive unit to control the movement of the surgical instrument within the degree(s)-of-freedom. The remote controller may have a user interface for receiving commands from a user, which may be movements made at the user interface that correspond to movements of the surgical instrument.
In accordance with a second aspect of the present inventions, a method of aligning a surgical instrument with a target region of a patient (e.g., an incision) is provided. The method comprises mounting a rigid template having a location element (e.g., a location ball) to a clamp associated with a rigid support that is affixed relative to a patient table. By way of non-limiting example, the rigid support may be a rigid post mounted to the patient table.
The method further comprises adjusting the clamp along a rigid support until the location element of the template aligns (e.g., laterally) with the target region, firmly securing the clamp to the rigid support, removing the template from the firmly secured clamp, and mounting the surgical instrument to the firmly secured clamp. In one method, surgical instrument has a rigid guide tube and a surgical insert disposed within the guide tube, in which case, the guide tube may be mounted to the firmly secured clamp.
An embodiment of a surgical robotic system of the present invention is illustrated in the accompanying drawings. The described embodiment is preferably used to perform minimally invasive surgery, but may also be used for other procedures such as endoscopic or open surgical procedures.
A master assembly 7 is associated with the master station M and a slave assembly 8 is associated with the slave station S. Assemblies 7 and 8 are interconnected by cabling 6 to a controller 9. Controller 9 has one or more display screens enabling the surgeon to view a target operative site, at which is disposed a pair of tools 18. The controller further includes a keyboard for inputting commands or data.
As shown in
Thus, the controller 9 couples the master station M and the slave station S and is operated in accordance with a computer program or algorithm, described in further detail later. The controller receives a command from the input device 3 and controls the movement of the surgical instrument in a manner responsive to the input manipulation.
With further reference to
Each of the two surgical instruments 14 is generally comprised of two basic components, an adaptor or guide member 15 and an instrument insert or member 16. The adaptor 15 is a mechanical device, driven by an attached cable array from drive unit 8. The insert 16 extends through the adaptor 15 and carries at its distal end the surgical tool 18. Detailed descriptions of the adapter and insert are found in later drawings.
Although reference is made to “surgical instrument” it is contemplated that this invention also applies to other medical instruments, not necessarily for surgery. These would include, but are not limited to catheters and other diagnostic and therapeutic instruments and implements.
In
Referring again to
Each surgical instrument 14 is mounted on a separate rigid support post 19 which is illustrated in
Each surgical instrument 14 is connected to the drive unit 8 by two mechanical cabling (cable-in-conduit) bundles 21 and 22. These bundles 21 and 22 terminate at connection modules, illustrated in
In a preferred technique for setting up the system, a distal end of the surgical instrument 14 is manually inserted into the patient through an incision or opening. The instrument 14 is then mounted to the rigid post 19 using a mounting bracket 25. The cable bundles 21 and 22 are then passed away from the operative area to the drive unit 8. The connection modules of the cable bundles are then engaged to the drive unit 8. One or more instrument inserts 16 may then be passed through the surgical adaptor 15, while the adapter remains fixed in position at the operative site. The surgical instrument 14 provides a number of independent motions, or degrees-of-freedom, to the tool 18. These degrees-of-freedom are provided by both the surgical adaptor 15 and the instrument insert 16.
The surgeon's interface 11 is in electrical communication with the controller 9. This electrical control is primarily by way of the cabling 6 illustrated in
In addition to the three degrees-of-freedom provided by the guide tube 17, the tool 18 may have three additional degrees-of-freedom. This is illustrated schematically in
In practice, an instrument insert 16 (carrying the inner shaft 309) is positioned within the adaptor 15 (including guide tube 17), so that the movements of the insert are added to those of the adaptor. The tool 18 at the distal end of insert 16 has two end grips 304 and 305, which are rotatably coupled to wrist link 303, by two rotary joints J6 and J7. The axis 308 of the joints J6 and J7 are essentially collinear. The wrist link 303 is coupled to a flexible inner shaft 302 through a rotary joint J5, whose axis 306 is essentially orthogonal to the axis 308 of joints J6 and J7. The inner shaft 309 may have portions of differing flexibility, with distal shaft portion 302 being more flexible than proximal shaft portion 301. The more rigid shaft portion 301 is rotatably coupled by joint J4 to the instrument insert base 300. The axis of joint J4 is essentially co-axial with the rigid shaft 301. Alternatively, the portions 301 and 302 may both be flexible.
Through the combination of movements J1-J3 shown in
The combination of joints J4-J7 shown in
The cannula 180 includes a rigid base 182 and a flexible end or stem 184. The base may be constructed of a rigid plastic or metal material, while the stem may be constructed of a flexible plastic material having a fluted effect as illustrated in
In the context of an insertable instrument system, there may generally be distinguished two types of systems, flexible and rigid. A flexible system would use a flexible shaft, which may be defined as a shaft atraumatically insertable in a body orifice or vessel which is sufficiently pliable that it can follow the contours of the body orifice or vessel without causing significant damage to the orifice or vessel. The shaft may have transitions of stiffness along its length, either due to the inherent characteristics of the material comprising the shaft, or by providing controllable bending points along the shaft. For example, it may be desirable to induce a bend at some point along the length of the shaft to make it easier to negotiate a turn in the body orifice. A mechanical bending of the tube may be caused by providing one or more mechanically activatable elements along the shaft at the desired bending point, which a user remotely operates to induce the bending upon demand. The flexible tube may also be caused to bend by engagement with a body portion of greater stiffness, which may, for example, cause the tube to bend or loop around when it contacts the more stiffer body portion. Another way to introduce a bend in the flexible shaft is to provide a mechanical joint, such as the wrist joint provided adjacent to tool 18 as previously described, which, as discussed further, is mechanically actuated by mechanical cabling extending from a drive unit to the wrist joint.
One potential difficulty with flexible shafts or tubes as just described is that it can be difficult to determine the location of any specific portion or the distal end of such shaft or tube within the patient. In contrast, what is referred to as a rigid system may utilize a rigid guide tube 17 as previously described, for which the position of the distal end is more easily determined, simply based upon knowing the relevant dimensions of the tube. Thus, in the system previously described, a fixed pivot point (205 in
Furthermore, by inserting the more flexible shaft, carrying a tool 18 at its distal end, within the rigid guide tube, the rigid guide tube in effect defines a location of the flexible shaft and its distal end location tool 18.
Also relevant to the present invention is the use of the term “telerobotic” instrument system, in which a physician or medical operator is manually manipulating some type of hand tool, such as a joy stick, and at the same time is looking at the effect of such manual manipulation on a tool which is shown on a display screen, such as a television or a video display screen, accessible to the operator. The operator then can adjust his manual movements in response to visual feedback he receives by viewing the resulting effect on the tool, shaft guide tube, or the like, shown on the display screen. It is understood that the translation of the doctor's manual movement, via a computer processor which feeds a drive unit for the inserted instrument, is not limited to a proportional movement, rather, the movement may be scaled by various amounts, either in a linear fashion or a nonlinear fashion. The scaling factor may depend on where the instrument is located or where a specific portion of the instrument is located, or upon the relative rate of movement by the operator. The computer controlled movement of the guide tube or insert shaft in accordance with the present invention, enables a higher precision or finer control over the movement of the instrument components within the patient.
In practice, the physician, surgeon or medical operator would make an incision point, inserting the flexible cannula previously shown. He would then manually insert the rigid curved guide tube until the distal point of the guide tube was positioned at the operative site. With the guide tube aligned in a single plane, the operator would clamp the guide tube at the support bracket 25 on post 19, to establish the fixed reference pivot point, (205 in
The other three movements J4-J7, are defined as setting the orientation of the instrument insert, and more specifically, a direction at which the tool is disposed with respect to the wrist joint. Central mechanical cables in the inner shaft cause motions J5-J7, J5 being the wrist movement and J6-J7 being the jaw movement of the tool. The J4 movement is for rotation of the inner shaft by its proximal axis, within the guide tube. These relative movements, and the position and orientation of the instrument insert, will be further described in a later discussion of an example of the computer algorithm for translating the movement at the master station to a movement at the slave station.
At the master station illustrated
A lower positioner assembly 50 is supported from the base piece 48. An upper positioner assembly 60 is supported above and in rotational engagement (see arrow J1 in
As shown in
In
The upper positioner assembly 60 has a main support bracket 63, supporting on either side thereof side support brackets 64 and 66. Side bracket 64 supports a pulley 65, while side bracket 66 supports a pulley 67. Above pulley 65 is another pulley 70, while above pulley 67 is another pulley 72. Pulley 70 is supported on shaft 71, while pulley 72 is supported on shaft 73.
Also supported from side support bracket 64 is another motor/encoder 74, disposed on one side of the main support bracket 63. On the other side of bracket 63 is another motor/encoder 76, supported from side support bracket 66. Motor/encoder 74 is coupled to the shaft 71 by pulleys 65 and 70 and associated belts, such as the belt 75 disposed about pulley 65. Similarly, motor/encoder 76 detects rotation of the shaft 73 through pulleys 67 and 72 by way of two other belts. The pulley 65 is also supported on a shaft coupling to pulley 70 supported by side support bracket 64. A further belt goes about pulley 70 so there is continuity of rotation from the shaft 71 to the motor/encoder 74. These various belts and pulleys provide a movement reduction ratio of, for example, 15 to 1. This is desirable so that any substantial movements at the master station are translated as only slight movements at the slave station, thereby providing a fine and controlled action by the surgeon.
Extending upwardly from main support bracket 63, is arm assembly 90 which includes a pair of substantially parallel and spaced apart upright proximal arms 91 and 92, forming two sides of a parallelogram. Arm 91 is the main vertical arm, while arm 92 is a tandem or secondary arm. The bottoms of arms 91 and 92 are captured between side plates 78 and 79. The secondary arm 92 is pivotally supported by pin 81 (see
The side plates 78 and 79 pivot on an axis defined by shafts 71 and 73. However, the rotation of the plates 78 and 79 are coupled only to the shaft 73 so that pivotal rotation, in unison, of the side plates 78 and 79 is detected by motor/encoder 76. This action is schematically illustrated in
As depicted in
The distal end of distal arm 96 is forked, as indicated at 95 in
The pivot member 100 has at its other end a disc 103 that rotates co-axially with a disc end 104 of hand piece 105. There is relative rotation between disc 103 and disc 104 about a pivot pin 106 (see
At the very distal end of the master station is a forefinger member 112 that rotates relative to end 114 of the hand piece 105. As indicated in
Reference is now made to
The detailed cross-sectional view of
In order to provide adjustment of the belts 149 and 150, adjusting screws are provided. One set of adjusting screws is shown at 157 for adjusting the position of the side support bracket 66 and thus the belt 149. Also, there are belt adjusting screws 158 associated with support plate 159 for adjusting the position of the encoder and thus adjusting the belt 150.
The opposite pulley 72 and its shaft 73 are supported so that the pulley 72 rotates with rotation of the yoke formed by side plates 78 and 79. A clamp 166 clamps the shaft 73 to the side plate and thus to the rotating yoke. This yoke actually rotates with the pin of shaft 73. For further support of the shaft 73, there are also provided bearings 168, one associated with the support bracket 63 and another associated with support piece 162.
Regarding the yoke formed by side plates 78 and 79, at one end thereof is a counterweight 80, as illustrated in
In practice, the following sequence of operations occur at master station M. After the instrument 14 has been placed at the proper operative site, the surgeon is seated at the console and presses an activation button, such as the “enter” button on the keyboard 31 on console 9. This causes the arms at the master station to move to a predetermined position where the surgeon can engage thumb and forefinger grips.
While observing the position of the tools on the video display screen 30, the surgeon now positions his hand or hands where they appear to match the position of the respective tool 18 at the operative site (OS in
Now when the surgeon is ready to carry out the procedure, a third keystroke occurs, which may also be a selection of the “enter” key. When that occurs the motors are activated in the drive unit 8 so that any further movement by the surgeon will initiate a corresponding movement at the slave end of the system.
Reference is now made to
C1—Slave Overview (
Reference is now made to
The clamping bracket 216 has a knob 213 that can be loosened to reposition the support rod 19 and tightened to hold the support rod 19 in the desired position. The support rod 19, at its vertical arm 19A, essentially moves up and down through the clamp 216. Similarly, the mounting bracket 25 can move along the horizontal arm 19B of the support rod 19, and be secured at different positions therealong. The clamp 214, which supports the drive unit 8 on the operating table, also has a knob 215 which can be loosened to enable the drive unit to be moved to different positions along the attaching member 212.
Reference is now made to
An adjustable bracket 25 and support post 19 may be provided at each side of the table for mounting a surgical instrument 14 on both the left and the right sides of the table. Depending upon the particular surgical procedure, it may be desirable to orient a pair of guide tubes on the left and right sides in different arrangements. In the arrangement of
In connection with the operation of the present system, once the patient is on the table, the drive unit 8 is clamped to the table. It's position can be adjusted along the table by means of the attaching member 212. The lower arm 19A of the rigid support rod 19 is secured to the table by the bracket 216. The surgeon determines where the incision is to be made. The mounting bracket on the rigid rod 19 is adjusted and the template 470 is secured to the clamp 25. The ball 474 on the template is lined up with the incision so as to position the securing rod 19 and clamp 25 in the proper position. At that time the rigid rod 19 and the securing clamp 25 are fixed in position. Then the template is removed and the instrument 14 is positioned on the clamp 25. The incision has been made and the guide tube 17 is inserted through the incision into the patient and the instrument 14 is secured at the fixed position of mounting bracket 25.
With regard to the incision point, reference is made to
C2—Slave Cabling and Decoupling (
In the present embodiment the cable conduits 21 and 22 are detachable from the drive unit 8. This is illustrated in
Also in
After insertion, the instrument assembly, with attached cables 21, 22 and housing 856, is attached to the support post 19 by means of the knob 26 engaging a threaded hole in base 452 of adapter 15. At the other end of the support post 19, bracket 216 has a knob 213 that is tightened when the support rod 19 is in the desired position. The support rod 19, at its vertical arm 19A, essentially moves up and down through the clamp 216. Similarly, the mounting bracket 25 can move along the horizontal arm 19B of the support rod to be secured at different positions therealong. A further clamp 214 enables the drive unit 8 to be moved to different positions along the attaching member 212.
Reference is now made to
Reference is now made to further cross-sectional views illustrated in
These cross-sectional views illustrate a series of seven motors 800, one for each of an associated mechanical cabling assembly. In,
A coupler disk 862 is illustrated in
The first housing section 855 also carries oppositely disposed thumb screws 875 (see
The cross-sectional view of
As illustrated in
In
At the top of the second housing section 856 there is provided a conduit stop or retainer 888 that is secured in place at the top of the housing section in an appropriate manner. The conduit retainer 888 has through slots 890, one for accommodating each of the cables A-G (see
In
The detachability of the two housing sections 855 and 856 enables the cleaning of certain components which are disposed above the plane of the operating table, here referred to as the sterile field. More specifically, the detachable housing 856 with attached cables 21 and 22 and instrument 14, needs to be sterilized after use, except for the instrument insert 16 which is an integral disposal unit. The sterilization of the designated components may include a mechanical cleaning with brushes or the like in a sink, followed by placement in a tray and autoclave in which the components are subjected to superheated steam to sterilize the same. In this manner, the adapter 15 is reusable. Also, the engagement between the adapter 15 and insert 16 is such that the disposable insert element may have holes, which are relatively hard to clean, whereas the recleanable adapter element has a minimum number of corresponding projections, which are relatively easier to clean than the holes. By disposable, it is meant that the unit, here the insert 16, is intended for a single use as sold in the marketplace. The disposable insert interfaces with an adapter 15 which is intended to be recleaned (sterilized) between repeated uses. Preferably, the disposable unit, here the insert 16, can be made of relatively lower cost polymers and materials which, for example, can be molded by low-cost injection molding. In addition, the disposable instrument insert 16 is designed to require a relatively minimal effort by the operator or other assistant who is required to attach the insert to the adapter 15. More specifically, the operator is not required to rethread any of the multiple mechanical cabling assemblies.
C3—Slave Instrument Assembly (
Further details of the detachable and portable slave unit are shown in
As indicated previously, a support yoke 220 is supported in a fixed position from the mounting bracket 25 via base 452. Cabling 21 extends into the support yoke 220. The support yoke 220 may be considered as having an upper leg 236 and a lower leg 238 (see
Disposed within a recess in the support yoke 220, as illustrated in
The base 240 of pivot piece 222 also has at one end thereof an end piece 241 into which are partially supported the ends of rails 224 (see
Now, reference is made to
Also extending from the base piece 234 is the guide tube 17 of adapter 15. The guide tube 17 accommodates, through its center axial passage, the instrument insert 16. Also, supported from the base piece 234, at pivot pin 232, is the adaptor coupler 230. The adaptor coupler 230 pivots out of the way so that the instrument insert 16 can be inserted into the adaptor 15.
With further reference to
The base piece 234 has secured thereto two parallel spaced-apart bars 270 and 272. It is between these bars 270 and 272 that is disposed the pivot pin 232. The pivot pin 232 may be supported at either end in bearings in the bars 270 and 272, and as previously mentioned, has limited sliding capability so as to move the adapter coupler 230 away from base piece 234 to enable insertion of the instrument insert 16. A leg 275 is secured to the pivot pin 232. The leg 275 extends from the coupler 230 and provides for pivoting of coupler 230 with respect to base piece 234. Thus, the combination of pivot pin 232 and the leg 275 permits a free rotation of the coupler 230 from a position where it is clear to insert the instrument insert 16 to a position where the coupler 230 intercouples with the base 300 of the instrument insert 16. As depicted in
The base piece 234 also rotatably supports the rigid tube 17 (illustrated by arrow J3 in
Also supported from the very proximal end of the tube 17, is a second pulley 279 that is supported for rotation about the actuator tube 17. For this purpose a bearing is disposed between the pulley 279 and the actuator tube. The pulley 279 is operated from another pair of cables in the bundle 271 that operate in the same manner. The cabling is such that two cables couple to the pulley 279 for operation of the pulley in opposite directions. Also, as depicted in
Again referring to
In this embodiment, the coupler 230 includes wheels 320, 322 and 324. Each of these wheels is provided with a center pivot 325 to enable rotation of the wheels in the coupler 230. The knob 327 is used to secure together the adapter coupler 230 and the base coupler 300 of the instrument insert 16.
For the three wheels, 320, 322 and 324, there are six corresponding pulleys 317, two pulleys being associated with each wheel (see
Each of the wheels 320, 322 and 324 have a half-moon portion with a flat side 329. Similarly, the instrument base 300 has companion wheels 330, 332 and 334 with complimentary half-moon construction for engagement with the wheels 320, 322 and 324. The wheel 320 controls one of the jaws of the tool 18 (motion J6 in
The coupler 300 of insert 16 has three wheels 330, 332 and 334, each with a pivot pin 331, and which mate with the corresponding wheels 320, 322 and 324, respectively of the adaptor coupler. In
As shown in
The instrument coupler 300 is also provided with a registration slot 350 at its distal end. The slot 350 engages with a registration pin 352 supported between the bars 270 and 272 of base piece 234. The coupler 300 is also provided with a clamping slot 355 on its proximal end for accommodating the threaded portion of the clamping knob 327 (on adapter coupler 230). The knob 327 affirmatively engages and interconnects the couplers 230 and 300.
In operation, once the surgeon has selected a particular instrument insert 16, it is inserted into the adapter 15. The proximal stem 301, having the distal stem 302 and the tool 18 at the distal end, extend through the adapter guide tube 17.
Reference is also now made to detailed cross-sectional views of
The base piece 234 of adapter 15 rotatably supports the guide tube 17, allowing rotation J3 shown in
A nylon bearing 368 is also provided between the second pulley 279 and the guide tube 17.
In
The link 601 is rotatably connected to the base 600 about axis 604.
Six cables 606-611 actuate the four members 600-603 of the tool. Cable 606 travels through the insert stem (section 302) and through a hole in the base 600, wraps around curved surface 626 on link 601, and then attaches on link 601 at 630. Tension on cable 606 rotates the link 601, and attached upper and lower grips 602 and 603, about axis 604 (motion J5 in
Cables 608 and 610 also travel through the stem 301, 302 and though holes in the base 600. The cables 608 and 610 then pass between two fixed posts 612. These posts constrain the cables to pass substantially through the axis 604, which defines rotation of the link 601. This construction essentially allows free rotation of the link 601 with minimal length changes in cables 608-611. In other words, the cables 608-611, which actuate the jaws 602 and 603, are essentially decoupled from the motion of link 601. Cables 608 and 610 pass over rounded sections and terminate on jaws 602 and 603, respectively. Tension on cables 608 and 610 rotate jaws 602 and 603 counter-clockwise about axis 605. Finally, as shown in
To review the allowed movements of the various components of the slave unit, the instrument insert 16 slides through the guide tube 17 of adaptor 15, and laterally engages the adaptor coupler 230. The adaptor coupler 230 is pivotally mounted to the base piece 234. The base piece 234 rotationally mounts the guide tube 17 (motion J3). The base piece 234 is affixed to the linear slider or carriage assembly (motion J2). The carriage assembly in turn is pivotally mounted at the pivot 225 (motion J1).
Reference is now made to
In
The two embodiments of
In the embodiment of
Regarding the operation of the tool, reference is made to the cables 608, 609, 610, and 611. All of these extend through the flexible stem section and also through the wall 665 such as illustrated in
By virtue of the slots 662 forming the ribs 664, there is provided a structure that bends quite readily, essentially bending the wall 665 by compressing at the slots such as in the manner illustrated in
The embodiment illustrated in
In another embodiment, the bending or flexing section 660 can be constructed so as to have orthogonal bending by using four cables separated at 90.degree. intervals and by providing a center support with ribs and slots about the entire periphery. This embodiment is shown in
The bending section has a center support wall 614 supporting ribs 618 separated by slots 619. This version enables bending in orthogonal directions by means of four cables 606,607,616 and 617, instead of the single degree-of-freedom of
Mention has also been made of various forms of tools that can be used. The tool may comprise a variety of articulated tools such as: jaws, scissors, graspers, needle holders, micro dissectors, staple appliers, tackers, suction irrigation tools and clip appliers. In addition, the tool may comprise a non-articulated instrument such as: a cutting blade, probe, irrigator, catheter or suction orifice.
C4—Slave Drive Unit (
Reference is now made to the perspective view of the drive unit 8, previously illustrated in
The drive unit includes a support plate 805 to which there is secured a holder 808 for receiving and clamping the cabling conduits 835. The motors 800 are each supported from the support plate 805.
Regarding support for the motors 800 there is provided, associated with each motor, a pair of opposed adjusting slots 814 and adjusting screws 815. This permits a certain degree of positional adjustment of the motors, relative to their associated idler pulleys 820. The seven idler pulleys are supported for rotation by means of a support bar 825.
The seven motors in this embodiment control (1) one jaw of the tool J6, (2) the pivoting of the wrist at the tool J5, (3) the other jaw of the tool J7, (4) rotation of the insert J4, (5) rotation of the adaptor J3, (6) linear carriage motion J2 and (7) pivoting of the adaptor J1. Of course, fewer or lesser numbers of motors may be provided in other embodiments and the sequence of the controls may be different.
Thus, if one of the motors is operating under tension, this is sensed by the load cell 840 and an electrical signal is coupled from the slave station, by way of the controller 9, to the master station to control one of the master station motors. When tension is sensed, this drives the master station motor in the opposite direction (to the direction of movement of the surgeon) to indicate to the surgeon that a barrier or some other obstacle has been encountered by the element of the slave unit being driven by the surgeon's movements.
The cabling scheme is important as it permits the motors to be located in a position remote from the adaptor and insert. Furthermore, it does not require the motor to be supported on any moving arms or the like. Several prior systems employing motor control have motors supported on moveable arms. Here the motors are separated from the active instrument area (and sterile field) and furthermore are maintained fixed in position. This is illustrated in
Another important aspect is the use of inter-mating wheels, such as the wheels 324 and 334 illustrated in
C5—Slave Guide Tube (
Reference is now made to
C6—Slave Motor Control (
Regarding the master station side, there is at least one position encoder associated with each of degree-of-motion or degree-of-freedom. Also, as previously described, some of the described motions of the active joints have a combination of motor and encoder on a common shaft. With regard to the master station, all of the rotations represented by J1, J2 and J3 (see
The block diagram of
The motor control system may be implemented for example, in two ways. In a first method the user utilizes the motor control subunit 706 to effect four control modes: positional control, proportional velocity control, trapezoidal profile control and integral velocity control. Using any one of these modes means specifying desired positions or velocities for each motor, and the necessary control actions are computed by the motion control IC 710 of the motor control subunit, thereby greatly reducing the complexity of the control system software. However, in the case where none of the on-board control modes are appropriate for the application, the user may choose a second method in which a servo motor control software is implemented at the PC control station. Appropriate voltage signal outputs for each motor are computed by the PC control station and sent to the motor control/power amplifier unit (706, 712). Although the computation load is mostly placed on the control station's CPU in this case, there are available high performance computers and high speed PCI buses for data transfer which can accommodate this load.
First, the joint sensors (box 435), which are optical encoders in the present embodiment, of the surgeon's interface system are read, and via forward kinematics (box 410) analysis, the current position (see line 429) and orientation (see line 427) of the input interface handle are determined. The translational motion of the surgeon's hand motion is scaled (box 425), whereas the orientation is not scaled, resulting in a desired position (see line 432) and orientation (see line 434) for the instrument tool. The results are then inputted into the inverse kinematics algorithms (box 415) for the instrument tool, and finally the necessary joint angles and insertion length of the instrument system are determined. The motor command positions are sent to the instrument motor controller (box 420) for commending the corresponding motors to positions such that the desired joint angles and insertion length are achieved.
With further reference to
The following is an analysis of the kinematic computations for both box 410 and box 415 in
The present embodiment provides a surgeon with the feel of an instrument as being an extension of his own hand. The position and orientation of the instrument tool is mapped to that of the surgeon input interface device, and this mapping process is referred to as kinematic computations. The kinematic calculations can be divided into two sub-processes: forward kinematic computation of the surgeon user interface device, and inverse kinematic computation of the instrument tool.
Based on the information provided by the joint angle sensors, which are optical encoders of the surgeon interface system, the forward kinematic computation determines the position and orientation of the handle in three dimensional space.
The position of the surgeon's wrist in three dimensional space is determined by simple geometric calculations. Referring to
X
p=(L3 sin θ3+L2 cos θ2a)cos θbp−L2
Y
p=−(L3 cos θ3+L2 sin θ2a)−L3
Z
p=(L3 sin θ3+L2 cos θ2a)sin θbp
where Xp, Yp, and Zp are wrist positions in the x, y, z directions, respectively.
These equations for Xp, Yp, and Zp represent respective magnitudes as measured from the initial reference coordination location, which is the location in
The reference coordinates for both the master and the slave are established with respect to a base location for each. In
The orientation of the surgeon interface handle in three dimensional space is determined by a series of coordinate transformations for each joint angle. As shown in
Where Rwh11=cos θbp1 cos θ2a
R
wh12=cos θbp1 sin θ2a cos θax−sin θbp1 sin θax
R
wh13=−cos θbp1 sin θ2a sin θax−sin θbp1 cos θax
R
wh21=−sin θ2a
Rwh22=cos θ2a cos θax
R
wh23=−cos θ2a sin θax
Rwh31=sin θbp1 cos θ2a
R
wh32=sin θbp1 sin θ2a cos θax+cos θbp1 sin θax
Rw
h33=−sin θbp1 sin θ2a sin θax+cos θbp1 cos θax
Similarly, the handle coordinate frame rotates joint angles φ and θh) about the z and y axes with respect to the wrist coordinate frame. The transformation matrix Rhwh for handle coordinate frame with respect to the wrist coordinate is then
where Rhwh11=cos φ sin θh
Rhwh11=cos φ cos θh
R
hwh12=−sin φ
Rhwh21=sin φ cos θh
Rhwh22=cos φ
R
hwh23=−sin φ sin θh
Rhwh31=sin θh
Rhwh32=0
Rhwh33=cos θh
Therefore, the transformation matrix Rh for handle coordinate frame with respect to the reference coordinate is
Rh=RwhRhwh
Once the position and orientation of the surgeon interface handle are computed, the instrument tool is to be moved in such a way that the position of the tool's wrist joint in three dimensional space Xw, Yw, Zw with respect to the insertion point are proportional to the interface handle's positions by a scaling factor α.
(Xw−Xw
(Yw−Yw
(Zw−Zw
where Xw
When Xw
Xw=αXp
Yw=αYp
Zw=αZp
where (Xw, Yw, Zw), (Xp, Yp, Xp,) and α are the desired absolute position of the instrument, current position of the interface handle and scaling factor, respectively.
The next task is to determine the joint angles ω, ψ and the insertion length Ls of the instrument, as shown in
where Lbs=Lb sin θb.
Referring to
L
w=√{square root over (Xw2+Yw2+Zw2)}
Then by the sine rule, the angle θa is
Having determined ω and Ls, the last joint angle ψ can be found from the projection of the instrument on the x-z plane as shown in
ψ=θL′w−θΔ
Where
L′w=√{square root over (Xw2+Zw2)} and Xwo is the x-axis wrist position in reference coordinate frame.
The last step in kinematic computation for controlling the instrument is determining the appropriate joint angles of the tool such that its orientation is identical to that of the surgeon's interface handle. In other words, the transformation matrix of the tool must be identical to the transformation matrix of the interface handle, Rh
The orientation of the tool is determined by pitch (θf), yaw (θwf) and roll (θaf) joint angles as well as the joint angles and ω and ψ as shown in
The wrist joint coordinate is then rotated about the reference coordinate by angles (−ψ) about the y-axis and ω about the z-axis, resulting in the transformation matrix Rw′f.
followed by rotation of (π/2−θb) about the y-axis, represented by Rwfw′f.
Finally, the tool rolls (−θaf) about the x-axis, yaws θwf about the z-axis and pitches (−θf) about the y-axis with respect to the wrist coordinate, are calculated resulting in transformation matrix Rfwf.
where Rfwf11=cos θwf cos θf
Rfwf12=−sin θwf
R
fwf13=−cos θwf sin θf
R
fwf21=cos θaf sin θwf cos θf+sin θaf sin θf
Rftf22=cos θaf cos θwf
R
fwf23=−cos θaf sin θwf sin θf+sin θaf cos θf
R
fwf31=−sin θaf sin θwf cos θf+cos θaf sin θf
R
fwf32=−sin θaf cos θwf
R
fwf33=sin θaf sin θwf sin θf+cos θaf cos θf
Therefore the transformation matrix of the tool Rf with respect to the original coordinate is Rf=RoRwf′RoTRfwf.
Since Rf is identical to Rh of the interface handle, Rfwf can be defined by Rfwf=RoRwf′TRoTRh=Rc
where the matrix Rc can be fully computed with known values. Using the computed values of Rc and comparing to the elements of Rfwf, we can finally determine the necessary joint angles of the tool.
θwf=arcsin(−Rc12),
The actuators, which are motors in the current embodiment, are then instructed to move to positions such that the determined joint angles and insertion length are achieved.
Now reference is made to the following algorithm that is used in association with the system of the present invention. First are presented certain definitions.
Note the motion boundaries of the slave are used to define the virtual boundaries for the master system, and do not directly impose boundaries on the slave system.
The following represents the steps through which the algorithm proceeds.
1. The system is started, and the position encoders are initialized to zero. This ASSUMES that the system started in predefined configuration.
2. Bring the system to operating positions, Des_Rad[i], and hold the positions until the operator hits the keyboard, in which case the program proceeds to next step.
3. Based on the assumption that the system started at the predefined configuration, the forward kinematic computations are performed respectively for the master and the slave systems to find the initial positions/orientations of handles/tools.
4. Repeat the procedure of computing initial positions/orientations of handle and tool of left hand based on predefined configurations.
5. Read starting time.
6. Read encoder values of master/slave system, and current time.
7. Compute current positions/orientations of master handle for Right Hand.
8. Desired tool position is computed for right hand.
9. Perform inverse kinematic computation for the right hand to obtain necessary joint angles of the slave system such that tool position/orientation matches that of master handle.
10. Repeat steps 7-9 for left hand system.
11. Determine motor axle angles necessary to achieve desired positions/orientations of the slave systems, and command the motors to the determined positions.
12. Go back to step 6 and repeat.
Previously there has been described an algorithm for providing controlled operation between the master and slave units. The following description relates this operation to the system of
The controller 9 receives input signals from the input device 3 that represent the relative positions of the different portions of the input device. These relative positions are then used to drive the instrument 14 to a corresponding set of relative positions. For example, the input 96 is rotatably connected to the first link at an elbow joint 94. Connected to the second link 96 opposite the elbow joint 94 is a wrist joint 98A and two fingers. A surgeon may attach a thumb and forefinger to the two fingers and move the input device to drive the instrument 14.
As the surgeon operates the input device, rotational position of the base (Thetabp1_m_RH), the rotational position of the first link relative to the base (Theta3_m_RH), the rotational position of the second link relative to the first link (Theta2_m_RH), the angle of the wrist joint relative to the second link (PHI_f_m_RH, i.e., the angle the wrist joint is rotated about an axis perpendicular to the length of the second link), the rotary angle of the wrist joint relative to the second link (ThetaAxl_m_RH, i.e., the angle the wrist joint is rotate about an axis parallel to the length of the second link), and the angles of the fingers (Theta_f1_m_RH and Theta_f2_m_RH) are provided to the controller.
When the surgical instrument is first started, the controller initializes all of the position encoders in the instrument 14 and the input device 3, assuming that the system has been started in a desired initial configuration. See Sections 1-3 of the algorithm. The initial position of the input device, e.g., Xwo_m_RH, Ywo_m_RH, and Zwo_m_RH, is then used to establish a reference position for the input device, Xwref_m_RH, Ywref_m_RH, and Zwref_m_RH. See Section 3 of the algorithm. Initial positions are also established for the instrument 14 based on the dimensions of the instrument 14. See Section 3 of the algorithm.
With reference to Section 3 of the algorithm, it is noted that there is an assignment of the initial position of the wrist for the slave, and that this is not a forward kinematics calculation based upon joint angles, but rather is a number based upon the predefined configuration of the slave unit. The coordinate of the slave relates to fixed physical dimensions of the instrument As the surgeon moves the input device 3, the encoder values for the input device are read and used to compute the current absolute position of the input device, i.e., Xw_m_RH Yw_m_RH, and Zw_m_RH. See Sections 6 and 7 of the algorithm. The controller then determines the desired position of the tool 18 (Xw_s_RH, Yw_s_RH and Zw_s_RH) based on the current position of the input device (Xw_m_RH Yw_m_RH, and Zw_m_RH), the reference position for the input device (Xwref_m_RH, Ywref_m_RH, and Zwref_m_RH) and the reference position for the instrument 14 (Xwref_s_RH, Ywref_s_RH, and Zwref_s_RH). See Section 8 of the algorithm. The desired position of the tool 18 (Xw_s_RH, Yw_s_RH, and Zw_s_RH) is then transformed by a 45.degree. coordinate transformation giving the desired position (Xwo_s_RH, Ywo_s_RH, Zwo_s_RH) which is used to determine joint angles and drive motor angles for the instrument 14 orientation to match that of the input device. See Sections 8-11 of the algorithm. Thus, movement of the surgical instrument 14 is determined based on the current absolute position of the input device, as well as the initial positions of the input device and the instrument at the time of system start-up.
The control in accordance with the present embodiment, as exemplified by the foregoing description and algorithm, provides an improvement in structure and operation while operating in a relatively simple manner. For example, the control employs a technique whereby the absolute position of the surgeon input device is translated into control signals to move the instrument to a corresponding absolute position. This technique is possible at least in part because of the particular construction of the instrument and controllable instrument holder, which essentially replace the cumbersome prior art multi-arm structures including one or more passive joints. Here there is initialized an all active joint construction, including primarily only a single instrument holder having a well-defined configuration with respect to the inserted instrument.
Some prior-art systems rely upon passive joints to initially position the distal tip of the surgical instrument. Because the positions of the passive joints are initially unknown, the position of the distal tip of the surgical instrument with respect to the robot (instrument holder) is also unknown. Therefore, these systems require an initial calculation procedure. This involves the reading of joint angles and the computation of the forward kinematics of all elements constituting the slave. This step is necessary because the joint positions of the slave are essentially unknown at the beginning of the procedure.
On the other hand, in accordance with the present invention it is not necessary to read an initial position of joint angles in order to determine an initial position of the distal tip of the surgical instrument. The system of the present invention, which preferably employs no passive joints, has the initial position of the distal tip of the surgical instrument known with respect to the base of the instrument. The instrument is constructed with known dimensions, such as between base pivot 225 and the wrist (303 at axis 306 in
The system of the present embodiment is fixed to the end of a static mount (bracket 25 on post 19) which is manually maneuvered over the patient, such as illustrated in
Another advantage of the present system is that the instrument does not use the incision in the patient to define a pivot point of the instrument. Rather, the pivot point of the instrument is defined by the kinematics of the mechanism, independent of the patient incision, the patient himself, or the procedure. Actually, the pivot point in the present system is defined even before the instrument enters the patient, because it is a pivot point of the instrument itself. This arrangement limits trauma to the patient in an area around the incision.
From an illustrative standpoint, the base of the instrument may be considered as pivot 225 (
The guide tube 17 may also have an alignment mark therealong essentially in line with the pivot 225, as shown in
Another advantage is the decoupling nature of the present system. This decoupling enables the slave unit to be readily portable. Here the instrument, drive unit and controller are decouplable. A sterilized adaptor 15 is inserted into a patient, then coupled to a non-sterile drive unit 8 (outside the sterile field). Instrument inserts 16 are then removably attached to the surgical adaptor to perform the surgical procedure. The system of the present embodiment separates the drive unit 8 from the instruments 16. In this way, the instruments can be maintained as sterile, but the drive unit need not be sterilized. Furthermore, at the time of insertion, the adaptor 15 is preferably decoupled from the drive unit 8 so it can be readily manually maneuvered to achieve the proper position of the instrument relative to the patient and the patient's incision.
In accordance with the present embodiment, the instrument inserts 16 are not connected to the controller 9 by way of any input/output port configuration. Rather, the present system employs an exclusively mechanical arrangement that is effected remotely and includes mechanical cables and flexible conduits coupling to a remote motor drive unit 8. This provides the advantage that the instrument is purely mechanical and does not need to be contained within a sterile barrier. The instrument may be autoclaved, gas sterilized or disposed in total or in part.
The present system also provides an instrument that is far less complex than prior art robotic system. The instrument is far smaller than that of a typical prior art robotic system, because the actuators (motors) are not housed in the articulate structure in the present system. Because the actuators are remote, they may be placed under the operating table or in another convenient location and out of the sterile field. Because the drive unit is fixed and stationary, the motors may be of arbitrary size and configuration, without effecting the articulated mechanics. Finally, the design allows multiple, specialized instruments to be coupled to the remote motors. This allows one to design an instrument for particular surgical disciplines including, but not limited to, such disciplines as cardiac, spinal, thoracic, abdominal, and arthroscopic.
A further important aspect is the ability to make the instrument disposable. The disposable element is preferably the instrument insert 16 such as illustrated in
The aforementioned disposable implement is purely mechanical and can be constructed relatively inexpensively, thus lending itself readily to being disposable. Another factor that lends itself to disposability is the simplicity of the instrument distal end tool (and wrist) construction. Prior tool constructions, whether graspers or other types, are relatively complex in that they usually have multiple pulleys at the wrist location for operation of different degrees-of-freedom there, making the structure quite intricate and relatively expensive to manufacture. On the other hand, in accordance with the present invention, no pulleys are required and the mechanism in the location of the wrist and tool is simple in construction and can be manufactured at far less expense, thus readily lending itself to disposability. One of the aspects of the invention that has enabled elimination of the pulleys, or the like, is the decoupling of tool action relative to wrist action by passing the tool actuation cables essentially through the center axis (604 in
Another aspect is the relative simplicity of the system, both in its construction and use. This provides an instrument system that is far less complex than prior robotic systems. Furthermore, by enabling a decoupling of the slave unit at the motor array, there is provided a readily portable and readily manually insertable slave unit that can be handled quite effectively by the surgeon or assistant when the slave unit is to be engaged through a patient incision or orifice. This enables the slave unit to be positioned through the incision or orifice so as to dispose the distal end at a target or operative site. A support is then preferably provided so as to hold a base of the slave unit fixed in position relative to the patient at least during a procedure that is to be carried out. This initial positioning of the slave unit with a predefined configuration immediately establishes an initial reference position for the instrument from which control occurs via a controller and user interface.
This portable nature of the slave unit comes about by virtue of providing a relatively simple surgical instrument insert in combination with an adaptor for the insert that is of relatively small configuration, particularly compared with prior large articulated robotic arm(s) structures. Because the slave unit is purely mechanical, and is decouplable from the drive unit, the slave unit can be readily positioned by the operator. Once in position, the unit is then secured to the support and the mechanical cables are coupled with the drive unit. This makes the slave unit both portable and easy to position in place for use.
Another advantage of the system is the ability to position the holder or adaptor for the instrument with its distal end at the operative site and maintained at the operative site even during instrument exchange. By way of example, and with reference to
Accordingly, one of the advantages is the ease of exchanging instruments. In a particular operation procedure, there may be a multitude of instrument exchanges and the present system is readily adapted for quick and easy instrument exchange. Because the holder or adaptor is maintained in position, the surgeon does not have to be as careful each and every time that he reintroduces an instrument into the patient. In previous systems, the instrument is only supported through a cannula at the area of the incision and when an instrument exchange is to occur, these systems require removal of the entire assembly. This means that each time a new instrument is introduced, great care is required to reposition the distal end of the instrument so as to avoid internal tissue or organ damage. On the other hand, in accordance with the present invention, because the holder or adaptor is maintained in position at the operative site, even during instrument exchange, the surgeon does not have to be as careful as the insert simply slides through the rigid tube adaptor. This also essentially eliminates any chance of tissue or organ damage during this instrument exchange.
Having now described a limited number of embodiments of the present invention, it should be apparent to those skilled in the art that numerous other embodiments and modifications thereof are contemplated as falling within the scope of the present invention.
This application is a continuation of co-pending U.S. application Ser. No. 11/562,960, filed Nov. 22, 2006, which is a continuation of U.S. application Ser. No. 10/012,845, filed Nov. 16, 2001 (now U.S. Pat. No. 7,169,141), which is a continuation-in-part of and claims the benefit of priority from U.S. application Ser. No. 09/827,503, filed Apr. 6, 2001 (now U.S. Pat. No. 6,432,112), which is a continuation of U.S. application Ser. No. 09/746,853, filed Dec. 21, 2000 (now U.S. Pat. No. 6,692,485), which is a divisional of U.S. application Ser. No. 09/375,666, filed Aug. 17, 1999 (now U.S. Pat. No. 6,197,017), which is a continuation of U.S. application Ser. No. 09/028,550, filed Feb. 24, 1998 (now abandoned). This application is also a continuation-in-part of and claims the benefit of priority from U.S. application Ser. No. 09/783,637, filed Feb. 14, 2001 (now abandoned), which is a continuation of PCT Application Ser. No. PCT/US00/12553, filed May 9, 2000, which claims the benefit of priority of U.S. Provisional Application Ser. No. 60/133,407, filed May 10, 1999. This application is also a continuation-in-part of and claims the benefit of priority from PCT Application PCT/US01/11376, filed Apr. 6, 2001, which claims priority to U.S. application Ser. No. 09/746,853, filed Dec. 21, 2000 (now U.S. Pat. No. 6,692,485), and Ser. No. 09/827,503, filed Apr. 6, 2001 (now U.S. Pat. No. 6,432,112). This application is also a continuation-in-part of and claims the benefit of priority from U.S. application Ser. No. 09/746,853, filed Dec. 21, 2000 (now U.S. Pat. No. 6,692,485) and Ser. No. 09/827,503, filed Apr. 6, 2001 (now U.S. Pat. No. 6,432,112). This application is also a continuation-in-part of and claims the benefit of priority from U.S. application Ser. No. 09/827,643, filed Apr. 6, 2001 (now U.S. Pat. No. 6,554,844), which claims priority to, inter alia, U.S. Provisional Application Ser. No. 60/257,869, filed Dec. 21, 2000 and U.S. Provisional Application Ser. No. 60/195,264, filed Apr. 7, 2000, and is also a continuation-in-part of PCT Application PCT/US00/12553, filed May 9, 2000 from which U.S. application Ser. No. 09/783,637, filed Feb. 14, 2001 (now abandoned), claims priority. This application also claims the benefit of priority under 35 U.S.C. §§ 119 and 120 to U.S. Provisional Application Ser. No. 60/293,346, filed May 24, 2001, U.S. Provisional Application Ser. No. 60/279,087, filed Mar. 27, 2001, U.S. Provisional Application Ser. No. 60/313,496, filed Aug. 21, 2001, U.S. Provisional Application Ser. No. 60/313,497, filed Aug. 21, 2001, U.S. Provisional Application Ser. No. 60/313,495, filed Aug. 21, 2001, U.S. Provisional Application Ser. No. 60/269,203, filed Feb. 15, 2001, U.S. Provisional Application Ser. No. 60/269,200, filed Feb. 15, 2001, U.S. Provisional Application Ser. No. 60/276,151, filed Mar. 15, 2001, U.S. Provisional Application Ser. No. 60/276,217, filed Mar. 15, 2001, U.S. Provisional Application Ser. No. 60/276,086, filed Mar. 15, 2001, U.S. Provisional Application Ser. No. 60/276,152, filed Mar. 15, 2001, U.S. Provisional Application Ser. No. 60/257,816, filed Dec. 21, 2000, U.S. Provisional Application Ser. No. 60/257,868, filed Dec. 21, 2000, U.S. Provisional Application Ser. No. 60/257,867, filed Dec. 21, 2000, and U.S. Provisional Application Ser. No. 60/257,869, filed Dec. 21, 2000. The disclosures of all of the foregoing applications and U.S. Pat. No. 6,197,017 are all incorporated herein by reference in their entirety. This application is also related to application Ser. Nos. ______, (Attorney Docket No. HNMD-EA004 CON2), ______ (Attorney Docket No. HNMD-EA004 CON3), ______ (Attorney Docket No. HNMD-EA004 CON5) and ______ (Attorney Docket No. HNMD-EA004 CON6), all of which are filed on the same date herewith. The disclosures of the foregoing applications are expressly incorporated herein by reference. This application further expressly incorporates herein by reference, U.S. application Ser. Nos. 10/014,145 (now U.S. Pat. No. 6,775,582), 10/012,845 (now U.S. Pat. No. 7,169,141), 10/008,964 (now abandoned), 10/013/046 (now abandoned), 10/011,450 (now abandoned), 10/008,457 (now U.S. Pat. No. 6,949,106), 10/008,871 (now U.S. Pat. No. 6,843,793), 10/023,024 (now abandoned), 10/011,371 (now U.S. Pat. No. 7,090,683), Ser. No. 10/011,449 (now abandoned), 10/010,150 (now U.S. Pat. No. 7,214,230), 10/022,038 (now abandoned), 10/012,586, all filed on Nov. 16, 2001.
Number | Date | Country | |
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60133407 | May 1999 | US | |
60257869 | Dec 2000 | US | |
60195264 | Apr 2000 | US |
Number | Date | Country | |
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Parent | 09375666 | Aug 1999 | US |
Child | 09746853 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 11562960 | Nov 2006 | US |
Child | 12024083 | US | |
Parent | 10012845 | Nov 2001 | US |
Child | 11562960 | US | |
Parent | 09746853 | Dec 2000 | US |
Child | 09827503 | US | |
Parent | 09028550 | Feb 1998 | US |
Child | 09375666 | US | |
Parent | PCT/US00/12553 | May 2000 | US |
Child | 09783637 | US | |
Parent | 09746853 | Dec 2000 | US |
Child | PCT/US01/11376 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 09827503 | Apr 2001 | US |
Child | 10012845 | US | |
Parent | 09783637 | Feb 2001 | US |
Child | 09028550 | US | |
Parent | PCT/US01/11376 | Apr 2001 | US |
Child | PCT/US00/12553 | US | |
Parent | 09746853 | Dec 2000 | US |
Child | PCT/US01/11376 | US | |
Parent | 09827503 | Apr 2001 | US |
Child | 09746853 | US | |
Parent | 09827643 | Apr 2001 | US |
Child | 09827503 | US | |
Parent | PCT/US00/12553 | May 2000 | US |
Child | 09827643 | US | |
Parent | PCT/US01/11376 | Apr 2001 | US |
Child | PCT/US00/12553 | US |