This invention relates to a carrying platform for moving a device such as a catheter within a conduit such as a blood vessel or other biological lumen.
Currently, catheters lack the ability to move deep inside narrow vessels, and at curvatures, risk damaging or even puncturing the vessel. Thus, it is desirable to have a standalone device which can be used together with existing catheters or scopes to assist doctors in navigating narrow vessels.
The carrying platform comprises a body having a longitudinal axis and a radial outer and inner surface. The body has a through hole along the longitudinal axis configured to receive a device with an elongate body therethrough, such as a catheter. The carrying platform has spaced apart external clampers on the radial outer surface, and an actuating mechanism which forms part of the hollow tubular body that allows the body to selectably extend or contract. Grippers that are spaced apart on the body are configured to be selectively activated to grip the device.
According to a first aspect, there is provided a carrying platform for moving a device within a conduit, the carrying platform comprising: a body configured to be moveable within the conduit; a number of clampers provided on the body and configured to releasably engage the conduit for immobilizing the carrying platform relative to the conduit; and a device engagement mechanism provided on the body and configured to releasably engage the device.
The device engagement mechanism may comprise at least a first set of wheels configured to effect relative movement between the carrying platform and the device and to allow the carrying platform to move along a length of the device within the conduit.
The body may comprise an actuating mechanism configured to selectably extend and contract the body; the number of clampers may comprise a front clamper and a rear clamper provided spaced apart on the body, the front clamper and the rear clamper each configured to independently engage the conduit such that a front portion of the body is immobilised relative to the conduit when the front clamper engages the conduit and a rear portion of the body is immobilised relative to the conduit when the rear clamper engages the conduit; and the device engagement mechanism may comprise a front gripper and a rear gripper provided spaced apart on the body, the front gripper and the rear gripper each configured to independently grip the device.
The carrying platform may be configured such that engaging the rear clamper with the conduit and extending the body when the front clamper is disengaged with the conduit results in forward movement of the front portion in the conduit, wherein engaging the rear clamper with the conduit and contracting the body when the front clamper is disengaged with the conduit results in backward movement of the front portion in the conduit, wherein engaging the front clamper with the conduit and extending the body when the rear clamper is disengaged with the conduit results in backward movement of the rear portion in the conduit, and wherein engaging the front clamper with the conduit and contracting the body when the rear clamper is disengaged with the conduit results in forward movement of the rear portion in the conduit.
When the rear gripper is not gripping the device, movement of the front gripper in the conduit when gripping the device may correspondingly move the elongate device in the conduit; and when the front gripper is not gripping the device, movement of the rear gripper in the conduit when gripping the device may correspondingly move the device in the conduit.
The front gripper and the rear gripper may each comprise one of: a sleeve made of a shape memory material, a sleeve actuated by wire to grip the elongate device, and a balloon configured to grip the device when inflated.
The body may have an inflatable wall comprising an external elastic layer and an internal elastic layer defining a space therebetween, wherein the external elastic layer is stiffed with fibres and the internal elastic layer is stiffened by a spring, and wherein the internal elastic layer defines a hollow passage through the body.
The front clamper may be provided with pressure supply lines that pass through the hollow passage, the pressure supply lines configured to cause bending of the body to occur when the inflatable wall is inflated and one of the pressure supply lines is pulled or held in place.
The carrying platform may further comprise an imaging modality that passes through the hollow passage.
The body may be hollow and may comprise a bellow.
The body may comprise a cylinder actuator having a piston-in-cylinder configuration, wherein the front clamper is provided on the piston and the rear clamper is provided on the cylinder.
The front clamper and the rear clamper may each comprise a balloon configured to engage the conduit when inflated.
Alternatively, the front clamper and the rear clamper may each comprise arms that engage the conduit when at rest, the arms being actuated by a wire to disengage with the conduit when the wire is pulled.
Alternatively, the front clamper and the rear clamper may each comprise arms that are disengaged with the conduit when at rest, the arms being actuated by a wire to engage with the conduit when the wire is pulled.
The carrying platform may further comprise a spring provided in the body wherein pulling a further wire compresses the spring to contract the body.
Gecko adhesive may be provided on the number of clampers at where the number of clampers are configured to engage the conduit.
The carrying platform may be configured to be connected to a further carrying platform of any preceding claim.
The carrying platform may be covered with an elastic layer configured to protect the carrying platform from substances found within the conduit.
In order that the invention may be fully understood and readily put into practical effect there shall now be described by way of non-limitative example only exemplary embodiments of the present invention, the description being with reference to the accompanying illustrative drawings.
Exemplary embodiments of the carrying platform 10 for moving a device 1 within a conduit will be described below with reference to
In general, the carrying platform 10 comprises a body 6 configured to be moveable within the conduit 7, and a number of clampers 2, 4 provided on the body 6 and configured to releasably engage the conduit 7 for immobilizing the carrying platform 10 relative to the conduit 7. The carrying platform 10 also comprises a device engagement mechanism provided on the body 6 and configured to releasably engage a device 1 within the conduit to effect relative movement between the carrying platform 10 and the device 1.
In a preferred embodiment, the carrying platform 10 is configured to be secured to the device 1 to ensure that it does not ever come off the device 1 particularly when the carrying platform 10 is inside a human body.
In one embodiment, as shown in
The front and rear clampers 2, 4 may each take the form of a balloon such that inflation of the balloon results in the clamper 2 or 4 engaging the conduit 7 in which the carrying platform 10 is placed.
The front and rear grippers 3, 5 are configured to grip the device 1 and may each take the form of a sleeve, a bulge, a spring, a membrane, an electromagnetic actuator, shape memory material, bimetal actuators, hydraulic or pneumatic actuators, electroactive polymers a noose, wire, strings, rotational wheels, or any form or configuration that allows controllable attachment and detachment of the carrying platform 10 with the device 1. This may or may not be selective to a specific location of the carrying platform 10 or the device 1. The sleeve may be made of a shape memory material, or wires may be provided to tighten the sleeve to actuate gripping. Alternatively, the front and rear grippers 3, 5 may each comprise a balloon such that inflation of the balloon results in the gripper 3 or 5 gripping the device 1. Activation or deactivation of the clampers 2 and 4 may be directly or indirectly coupled to the activation or deactivation of the grippers 5 and 3 respectively.
The front and rear clampers 2, 4 are configured such that a front portion of the body where the front clamper 2 is provided is immobilised relative to the conduit 7 when the front clamper 2 engages the conduit 7, and a rear portion of the body where the rear clamper 4 is provided is immobilised relative to the conduit 7 when the rear clamper 4 engages the conduit 7. Thus, the carrying platform may be said to comprise three sections or portions—a front portion comprising the front clamper 2 and front gripper 3, a rear portion comprising the rear clamper 4 and rear gripper 5, and the body 6 being a third portion that can be extended and contracted.
In one embodiment, the front clamper 2 and the rear clamper 4 each includes at least one gripper, the front gripper 3 and the rear gripper 5 respectively. The two clampers 2, 4, and two grippers 3, 5 are connected with the body 6.
When the carrying platform 10 is in use, the length of the extension part or body 6 can be adjusted in a way to cause the carrying platform 10 to extend or contract, resulting in forward or backward motion, with or without the movement of the device 1 itself, as will be described below. Note that this locomotion technique, traditionally termed “inchworm locomotion,” is exemplary, and can be replaced by any other locomotion technique such as earthworm, snake, jet, amoeboid, wheels based, and any other locomotion technique that is suitable for carrying or stabilizing the device 1 inside the conduit 7. For example, as shown in
Alternatively, forward motion of the carrying platform 10 can be achieved by inflating the first balloon or rear clamper 4 to engage or establish a grip on the wall or internal surface of a lumen 7 in which the carrying platform 10 is placed before extending the actuating mechanism to advance the body 6. After extending the body 6, the first balloon 4 is deflated while the second balloon or front clamper 2 is inflated to engage or establish a grip on the far end or internal surface of the lumen 7. The actuating mechanism then retracts and contracts the body 6, thereby moving the first balloon 4 forward. Repeating the above sequence of events moves the carrying platform 10 forward in the lumen. Appropriate use of the internal front and rear grippers 3, 5 that can be activated to grip the device 1 thus allow the carrying platform 10 to move the device 1 along the lumen during the forward motion. Various possibilities of motion can be achieved with the independent activation of the internal grippers 3, 5.
In a first instance as shown in
In a second instance as shown in
While the motion cycle described above with reference to
In addition, as shown in
Another important application arising from this design can be seen in
To allow for a higher navigation capability of the carrying platform 10, and in particular to increase pulling force on the elongate device 1, several carrying platforms 10 can be used simultaneously, for example, either by being chained together or attached or provided at intervals along the device 1. The connected carrying platforms 10 can either advance together with the device 1 or be detached from it at some point while continuing to propel the device 1 from its midsection along the desired path, or simply be deployed locally to reduce the friction between device 1 and walls 7.
When the space to be navigated comprises a larger divergence of distances between the wall or conduit and the carrying platform 10, i.e., when cross-sectional area of the conduit varies, for example when moving in both smaller and larger arteries), it is envisaged that the elongate device 1 to be moved may be equipped with carrying platforms 10 of different sizes to be utilized at different locations along the navigated path, according to the required diameter or distance of the conduit, to facilitate movement of the elongate device 1 in the conduit of varying internal cross-sectional area. Likewise, the carrying platform 10 may be equipped with several kinds of clampers for each diameter or gap range and for other functions. For example, clampers that are more suitable for force opening clogged vessels, clampers that are more suitable for sealing-off a portion of vessel for drug delivery, clampers that allow continuation of blood flow, clampers that include a photocatalytic function, clampers that have an active agent, such as drug emitted or embedded in them, clampers that can better sense properties of the environment or the wall, and so on. Likewise, a single clamper may be fitted to exhibit any one of these traits separately or at the same time.
Another possibility is to include more than one extensor or body 6, or more than two clampers 2, 4 in the carrying platform 10, in order to provide greater stability, higher force etc. Providing several carrying platforms at locations along the catheter line is especially useful as a larger diameter carrying platform is cheaper to produce which means that the carrying platform can be positioned along the line where the vessel diameter is larger, whereupon it will push the catheter from a point along the line where the carrying platform is located through the blockage.
To overcome blockages in a vessel, the extensor or body 6 and front clamper 2 can be repeatedly actuated, to aid navigation of the carrying platform 10 in the conduit. This ramming of clots, together with active chemicals or drugs that can be secreted, can be used to breakdown blockages. In addition, vibrations may be produced by the carrying platform 10 in order to overcome vessel blockage, while expandable (stent-like) rings or other similar structures can be deployed from the carrying platform 10 when needed. Said rings or structures can be biodegradable. It is also envisaged that secretion of dissolving or other active agents can be performed by the carrying platform 10 to clear blockage in the conduit.
One possible manufacturing process of the carrying platform 10 is illustrated in
One possibility of implementation of mounting the carrying platform 10 to a catheter 1 or other elongate device 1 is illustrated in
To improve navigation capability of the carrying platform 10, flexible hinges 12 that allow bending of the carrying platform 10 may be placed at edges of the extensor or body 6, whether or not the extensor or body 6 is itself flexible, as shown in
Encapsulating, or coating the carrying platform with a thin coating, layer or sheet of elastic material 9 as shown in
Another possibility when using a piston extensor for the body 6 is to orientate the piston extensor with the cylinder portion forward and the piston rod rearward such that the rear clamper 4 is provided on the piston rod while the front clamper is provided on the cylinder, so as to allow for a greater pushing force.
To allow bending of the carrying platform 10, it is possible to incorporate a nonconcentric balloon, that is, a balloon that is thicker or stiffer on one side, as one or both of the front and rear clampers 2, 4, in order to have a bending, or a bending-extension motion. It is also possible to embedded stiffness adjustable materials that can change their stiffness in response to electrical stimuli of other stimuli alternatives. It is also possible to embed fibers or springs inside or outside the balloon walls of the front and/or rear clampers 2, 4 in order to induce an axial or bending motion. Using springs will have the added benefit of increasing mechanical stability and return force.
The carrying platform 10 described in the above embodiments describe use of balloons and piston-cylinder actuators as fluidic actuators. However, bellows or spring-embedded balloons, can be equally good or even better candidates to replace these pistons. In addition, the front balloon 2 inlet can pass inside or through the extensor body 6 as shown in
Another possibility is using a “gauss gun-inspired piston” wherein the piston or another actuator configuration is actuated by electrical current or electromagnetism rather than a hydraulic or pneumatic pressure or pressure that is derived from chemical reaction or reversible chemical or physical reaction. In an embodiment of the carrying platform 10, the piston rod is connected to a strong magnet located inside the cylinder while the cylinder is enwrapped by sections of conductive coil. Running direct current inside these coils will generate a controlled magnetic field inside the cylinder that can be used to induce a very precise actuation. This technology is currently used in anti-aircraft guns for replacing gun power-based bullets allowing a very high rate of fire. However, many other types of more common electromagnetic actuators are available and can be used for this.
In another embodiment of this invention, the carrying platform 10 may comprise magnets and magnet-attracted material, said magnets can be induced to generate motion to carry the catheter 1 or endoscope 1 from outside a patient by control of the movement and location of these magnets by a magnetic field that is induced by a device that is external to the patient. This can be desirable as such configuration does not require channels to connect the platform directly to an external controller. Moreover, this can allow the fabrication of a smaller profile carrying platform 10 at lower costs.
Bending strings or additional supply lines 24 are provided to either act as additional supply lines of the front clamper 2 or the middle extensor body 6 or for an inflatable tip. Additionally they 24 can be used as a payload delivery mechanism. These additional supply lines 24 pass through the hollow section of the carrying platform 10 and are secured to stiffening rings of both the extensor body 6 and the front clamper 2. Holding in place or pulling one of these lines 24 during inflation of the middle extensor body 6 will cause bending of the carrying platform 10 in the direction of the line that is being held. The motion can be extended into an extension-bending motion if the supply line 24 is slightly released during or after the extensor inflation.
The stiffening return spring 26 embedded within the internal elastic balloon of the middle extensor body 6 both increases the pulling force of the carrying platform 10 during contraction, and also prevents collapse of the internal elastic layer of the extensor body 26 during inflation. A rigid cylinder 28 is provided in the interior of the rear clamper 4. This cylinder 28 prevents collapse of the rear clamper 4 into the hollow section of the body 6 during inflation of the rear clamper 4. The cylinder 28 can also include the rear gripper (not shown). A rigid cylinder 30 is provided in the interior of the front clamper 2. This cylinder 30 prevents collapse of the front clamper 2 into the hollow section of the body 6 during inflation of the front clamper. The cylinder 30 can also include the front gripper (not shown). An imaging modality 18, or an additional payload channel is additionally provided that passes through the hollow passage of the navigation carrying platform 10.
The combination of both a spring and a fiber stiffened balloon in the body can be beneficial as it allows a weaker spring with less axial resistance. In addition, having many fibers between the spring wire can improve the effects of axial expansion or extension of the body by blocking any lateral expansion or inflation of the body into gaps formed between the spring after the distance between the spring wires increases as a result of stretching of the spring; the same principle can be achieved by overlapping several layer of fiber stiffened sheet.
The advantage of such a carrying platform 10 as described above with reference to
In alternative embodiments, a hollow configuration of the carrying platform 10 may be achieved by linking torus-shaped balloons having supports in their interior. Balloons can be inflated in chain to induce earthworm-like locomotion or be used to make inchworm like locomotion as described thus far. Additional alternative designs may include use of bellows, or a spring-embedded or fiber-embedded balloons in the midsection. Designs that use shape memory, wire-actuated, electroactive actuators, etc. rather than fluidic actuators may also be used. To make a hollow balloon based device, a supporting scaffold can also be used.
One of the advantages of a hollow carrying platform is applying it for use in procedures that requires continued blood flow or in places like the trachea as it will allow continued breathing. A hollow carrying platform can also be applied as a local pump or blood pump. When there is a problem with blood flow, the balloon in the carrying platform can be activated in sequence and be used to pump blood with contraction movements into an oxygen deprived area or to breakdown clots etc. When attempting to deliver a payload such as a drug, active agent, marker, etc. to a targeted section of the vessel or conduit using a hollow carrying platforms, while this hollow carrying platform is designed to allow fluid flow, it may be beneficial to add a controllable flow blocking mechanism to allow flow blockage, resulting in a better delivery to the required region. Balloons used in the mentioned configurations, and additional balloons specifically added along the supply lines or others, can be used for generation of these sealed-off regions or to manipulate the movement of the carrying platform as shown in
Another implementation of the carrying platform is not to use hydraulic or electrically actuated actuators, but wire-controlled actuators as shown in
As shown in
An alternative embodiment of a wire or cable actuated carrying platform 10 is depicted in
A further exemplary embodiment of the carrying platform 10 is shown in
The exemplary carrying platform 10 shown in
To improve navigation and specifically to bolster the ability of the carrying platform to perform turns (in a junction, etc.) or pass clogged surfaces, a magnet or a ferromagnetic material or any type of material that can be effected by magnetic field can be provided, such as installed at its tip, or at any other suitable location on the carrying platform. This will allow application of an external magnetic field that can enable faster movement and sharper turns and higher force while advancing the carrying platform that is guiding the catheter 1 or endoscope 1.
In addition to improving navigation capability, magnets or compressible materials can also be used instead of a return spring in the extensor body to contract the body, allowing easier miniaturization of the piston cylinder if that is being used as an actuator. The same magnets can be used as a navigation aid as described above.
To achieve bending motion with balloons, in addition to the above described methods, overlap while rolling or wrapping an elastic sheet over a spring or overlapping the rolled elastic sheet with fibers embedded in it or using a material with stiffness or elasticity that can be controlled can be used to induce a bending motion in the body. If the overlap is not symmetric, having a part of the roll slightly thicker, the balloon of the body will bend in this thicker direction while expanding. The same principle can be achieved if a fiber or a flexible rod is added to one side of the balloon of the body in the direction of expansion. It is noteworthy to mention that while thicker sections will allow significant bending of over 360 degrees, if a spring is used, these will be harder to achieve as the spring stabilizes the structure, which in turn can be a benefit.
In addition to the above stiffening-induced bending, directional bending can be achieved by including structures with electroactive material or other smart materials with the carrying platform. Such materials can actively induce bending but can also operate passively by controllably adjusting their stiffness.
Another possible configuration to allow bending of the carrying platform is having a rotatable bending tip, eliminating the need of linking several tips. Having several separate compartments within the same tip can also enable multidirectional bending capacity, while having such said compartment on the sides of the extensor body can also induce bending without the need of an additional tip.
Providing an additional clamper at the end of the bending tip, or providing the additional clamper after the bending apex can result in a better design by allowing the carrying platform to clamp and immobilize at the desired location, thus stabilizing the operation.
Where the body is actuated using a piston mechanism or other actuators, the rear clamper does not necessarily need to be mounted behind the piston body. Having the rear clamper mounted in front on the cylinder near the piston seal will result in shorter distance between the rear and the front clamper which will enable higher degree of motion in bending and may reduce the cross-sectional diameter of the carrying platform. Controlled rotation of the piston rod (by pumping back and forth, for example) will allow the usage of a single bending tip for a full 3-DOF. If the rear clamper is located on the flexible pressure supply tubes in addition to rather than on the rigid piston—a higher degree of bending will allow the carrying platform to bend under pressure.
Despite the diversity of configuration described herein that suggest possible ways to enable controlled pitch and turn of the carrying platform, one must understand that the big advantage of this invention is that it can be added onto conventional catheters. If the carrying platform is used for catheterization without a catheter, meaning it is being operated as a catheter replacement, these bending abilities will become crucial. The main advantage and novelty of this invention is that it allows an improvement of conventional catheters. The bending and rotation of catheters is currently well established and in many cases performing very well. As such, the carrying platform does not need to be equipped with these abilities but only abilities that help in the forward and backward propulsion of the catheter 1 that it carries. The bending and rotation will come from the catheter 1 itself.
Adding gecko, treefrog, mushroom, beetle, or any kind of structural based or chemical-based or physics-based adhesive or any combination of adhesives to the front and rear clampers of the carrying platform is of a particular advantage. This family of adhesives is well studied and easy to fabricate (hemocompatible elastic gecko-like and beetle-like sheets made by medical grade silicone are commercially available at low prices). The gecko adhesive works best in a way that it adheres best when a lateral force is applied. It is a friction-based adhesive. This means that when the front or rear clamper presses against the wall of the conduit and the extensor body applies a lateral force as it extends or contract during the motion cycle, the gecko inspired adhesive will provide extra grip to the engagement of the front or rear clamper with the conduit and compensate friction deficit in slippery, or smooth environments.
Preferably, the carrying platform may be wirelessly powered using such wireless powering sources such as RF charging, magnetic induction, focused ultrasound, battery, utilizing the energy derived from the flow surrounding the carrying platform, and so on.
In addition to using the carrying platform's own fluidic system, therapeutic or active payloads carried by the carrying platforms described above can be numerous: photocatalytic and electrocatalytic arms and stents can be used, possibly operated by the carrying platform's own imaging modality by switching to a different wavelength; active-nanoparticles and medicine can be entrapped using an encapsulating mesh coating the internal part of the hollow carrying platform or located on a separate appendix or on the covering sheet of the carrying platform or the external areas of the carrying platform. These particles can be released possibly by changing the wavelength of the imaging modality. For example, pulling an imaging fiber to different locations relative to the carrying platform can enable more release flexibility, several agents, etc. Alternatively, a releasing/activating agent can be introduced via the carrying platform's fluidic system to initialize the reaction. Another possibility is to utilize focused ultrasound to release the trapped particles. Addition of separate compartments containing drugs or agents onto the carrying platform is also a possibility, these compartments will release the drug or agent particles when required.
The carrying platforms described above can be equipped with pressure sensors, such as on the clampers or extensor body, etc. Thin and flexible sensors with micron sensing resolution can be installed on the outer section of the clamper, directly contacting the walls or conduit. While this can be used as a safety measure to prevent over pressing sensitive walls, the application can also be extended as a sensory module, much like an artificial finger. This can enable detection of arterial stiffness, mapping of arterial plaques, detecting calcification of tubes etc. and even be used as an early warning for future arterial disease. If a wire actuated system is used, the wire can serve as an instant force sensor. The force exerted in order to pull the wires can be measured and directly translated to the force that is needed in order to activate the clamper, this can be instantly shown when contact with the artery is made.
In addition to moving catheters, the suggested carrying platform can be used as search and rescue robots, navigating between pieces of rubble; as inspection and maintenance carrying platforms for piping systems and the like, in such cases the flow from the pipe can be used to power the carrying platform and make it completely wireless; as swimming carrying platforms with particular advantage in high viscosity liquids; as digging robots; as carrying platforms able to navigate between walls, such as between two buildings. This might be of use in defense applications, where reconnaissance is needed in urban warfare, or for the deployment of weaponry or as surveillance/reconnaissance carrying platforms via piping systems or at the higher floors of a building in a very densely constructed area, where images from conventional drones are harder to obtain; the device can also be used in aircon conduits or any other conduits where access is needed. In addition, and especially if an adhesive such as gecko, electro-activated or other types of adhesives are added, the carrying platforms are not limited to navigation between walls. The carrying platforms are capable of moving on a single horizontal or tilted wall and surfaces due to friction differences between retracted and contracted clampers.
All the carrying platforms described above can be extended to applications where they navigate to and stay in a targeted location. Upon deployment they can be used for slow release of therapeutic or functional agents, as stents, lab-on-chip sensors etc. Using a clearance seal for the piston actuator enables a steady and controlled flow of saline-anticoagulant mix into a blood vessel to prevent clotting formation when using the carrying platform in a blood vessel. The targeted delivery of drugs, using leaks in the carrying platform as described above can be further expanded into other applications, such as pipes or any conduit system maintenance. Active agents can be locally or continuously delivered using the described carrying platform. In the human body, the carrying platform can be released from the catheter it is carrying and be deployed locally to gather information and or deliver payload in a controlled manner. The carrying platform is hollow and allows the continuation of the biological flow. The carrying platform can be removed using a catheter or other surgical operation or be absorbed by the body if it is made from biodegradable materials. One can also envision that the carrying platform may be incorporated with cell differentiation factors to serve as a scaffold for organ regeneration such as blood vessel, heart tissue, bone, muscle, etc.
Whilst there has been described in the foregoing description exemplary embodiments of the present invention, it will be understood by those skilled in the technology concerned that many variations in details of design, construction and/or operation may be made without departing from the present invention. For example, while the clampers have been described as each possibly comprising a balloon, other known mechanisms may be provided as the clampers so long as actuating of the clamper engages a portion of the carrying platform with the conduit, for example, fluidic actuators or actuators that are controlled by physical and chemical reactions, such as actuators that are controlled by melting and solidifying wax, magnets from outside the body, shape memory materials, electromagnetic, electroactive, ionic polymers, bimorph or bimetallic strips, dielectric elastomers, or even biological muscles controlled by electric stimuli. While the grippers have been described as each possibly comprising a sleeve or a balloon, other known mechanisms can be used for the grippers, so long as actuating of the gripper causes the gripper to grip the device, for example, electromagnetic, wires, bimetallic or SMA strips, or tissue engineered muscles that will be extremely biocompatible for long uses as it can be powered by nutrients from the blood.
Number | Date | Country | Kind |
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10201406164Y | Sep 2014 | SG | national |
Filing Document | Filing Date | Country | Kind |
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PCT/SG2015/050352 | 9/29/2015 | WO | 00 |