Medical device with constant cable length

Abstract

This application is entitled "Medical Device with Constant Cable Length." A device includes a wrist, an end effector, a cable pair, and a transmission. A proximal wrist portion is coupled to a distal portion of a shaft. Actuation of the wrist causes the distal wrist portion to move relative to the proximal wrist portion. The end effector is coupled to the distal wrist portion and is actuatable to move relative to the wrist. The transmission is coupled to a proximal end portion of the shaft and is capable of moving an end of the cable pair to actuate the end effector. The end of the cable pair is routed through a transmission cable path within the transmission. The transmission includes an adjustment mechanism having an input portion that receives a force exerted by the end of the cable pair. The adjustment mechanism is configured to change a length of the transmission cable path in response to a change in the force.

Description

[0001] This application is a divisional application of Chinese patent application 201780083152.4 (PCT / US2017 / 062258) entitled "Medical device with constant cable length" filed on November 17, 2017.

[0002] Cross-referencing related applications

[0003] This application claims priority to U.S. Provisional Patent Application No. 62 / 424,744 entitled “Cable Length Conserving Medical Instrument” (filed November 21, 2016), the entire contents of which are incorporated herein by reference. Technical Field

[0004] The embodiments described herein relate to mechanisms for maintaining a constant cable length, more specifically to medical devices, and even more specifically to endoscopic tools. More specifically, the embodiments described herein relate to devices including mechanisms for maintaining a constant cable length within the range of motion of the wrist joint. Background Technology

[0005] Many known medical devices used in minimally invasive surgery utilize one or more joints or wrists along a slender axis, sometimes referred to as the main axis of the medical device. Typically, the wrist provides multiple degrees of freedom of movement, and distal tools, such as biopsy needles, scalpels, forceps, scissors, or electrocautery tools, may be attached to or incorporated at or near the distal end of the main axis. Such known wrists are typically operated via cables that extend through the instrument's spindle and connect to a drive system in the transmission or actuator (also known as the backend). This backend is usually located proximally to the medical device and can be configured to engage or interface with a robot that mechanically powers the backend to move the cables, thereby manipulating the wrist. For robotic or remote operating systems, the backend mechanism is motor-driven and can be operatively coupled to a processing system to provide a user interface for controlling the instrument. During minimally invasive surgery, a physician can operate the system to insert the distal portion of the medical device through a small incision, catheter, or natural lumen until the distal tip of the device is at the working site within the patient's body. The physician can then operate the robot to drive the cables and control the wrist as needed to move the distal tool and perform clinical functions at the working site.

[0006] Known medical devices define one or more cable paths through which cables are routed from the rear end across the device axis and to the wrist. Because known wrists offer multiple degrees of freedom, the cable paths (and therefore the length of the cables traversing these paths) can change when the medical device is in use. For example, when some known wrists rotate about a pitch axis, the cable path length of cables routed on a first side of the pitch axis increases, while the cable path length of cables routed on a second (or opposite) side of the pitch axis decreases. An increased cable path length tends to stretch the cable or increase tension in the cable on the first side of the pitch axis, while a decreased cable path length allows the cable on the second side of the pitch axis to become slack or operate under reduced tension. Generally, it is desirable to maintain tension in the cable within a suitable range to prevent slack cables from derailing and to prevent taut cables from deforming or damaging other components. Therefore, some known medical devices include cable paths within the wrist that are routed to minimize changes in cable path length during actuation. This is sometimes referred to herein as cable length conservation.

[0007] For example, Figures 1A and 1B show a top and side view of a known medical device 100. The medical device 100 includes a wrist 130 located distal to a main shaft 120 and actuated via a rear end 110. The wrist 130 includes driven mechanisms 140 and 150, which together enable multiple degrees of freedom of movement. In the illustrated configuration, driven mechanism 140 is a joint actuated to provide a degree of freedom corresponding to pitch motion. Driven mechanism 140 includes a link 142 coupled to the main shaft 120 and a link 144 coupled to driven mechanism 150. A pair of cables 126a and 126b coupled to driven mechanism 140 extend through the main shaft 120 and are coupled to a drive mechanism (not shown) in the rear end 110. Therefore, as shown in Figure 1C, the drive mechanism can pull either cable 126a or 126b to rotate link 144 (and the more distal portion of medical device 100) relative to link 142.

[0008] The driven mechanism 150 (also referred to as the end effector) includes jaws 152 and 154, which act as another degree of freedom of the wrist (e.g., yaw motion) when they rotate together, and as surgical tools, such as forceps or scissors, when they rotate in opposite directions. Jaws 152 and 154 are mounted on a pivot 156, which can be offset to and perpendicular to the rotational axis 146 (i.e., pitch axis) of the joint 140. A pair of cables 122a and 122b are coupled to jaws 152 and extend through the joint 140 and the spindle 120 to a drive mechanism 112 in the rear end 110, and the drive mechanism 112 can pull cables 122a or 122b to rotate jaws 152 about the pivot 156. Similarly, another pair of actuated cables 124 are coupled to gripper 154 and extend through driven mechanism 140 and spindle 120 to rear end 110, and another drive mechanism (not shown) in rear end 110 can pull either of the cables 124 to rotate gripper 154 about a shared pivot 156. Figure 1B illustrates how drive mechanism 112 for cables 122a and 122b can include a winch 112 from which cables 122a and 122b extend. In use, an actuator (such as a motor controlling a robot) can rotate winch 112 to wind in or unwind cable 122b or 122a of a certain length and simultaneously release cable 122a or 122b of the same length, resulting in rotation of gripper 152. Another motor and winch (not shown) can drive cables 124 to rotate gripper 154.

[0009] As shown in Figure 1A, cables 122 and 124 have intersecting paths and are routed through the rotation axis 146 of joint 140, such that rotation of joint 140 does not change the path length of cables 122 and 124 between the rear-end mechanism 110 and the driven mechanism 150. In this way, even when joint 140 moves about the pitch axis 146, the cable paths within joint 140 maintain a substantially constant length for cables 122 and 124 between the rear-end mechanism 110 and the driven mechanism 150 (see, for example, Figure 1C). Therefore, this known connector assembly can be considered a cable length-constant device.

[0010] However, in some cases, defining a cable length-constant path within the wrist joint is impractical. For example, medical devices that include numerous functional elements or other components (e.g., wires) routed to an end effector may not be suited to a cable length-constant path. Similarly, medical devices containing joints with small cross-sectional areas or diameters may not have sufficient space to accommodate the routing of multiple cables for cable length constancy. In particular, as wrist architectures for medical devices are shrinking to diameters of 5 mm or less, space constraints make it challenging to achieve joints with cable length-constant paths while still using cables of sufficient strength to meet required medical capabilities.

[0011] Therefore, improvements are needed to accommodate the different cable path lengths between the distal and proximal ends of medical devices caused by the range of motion of the distal components. Summary of the Invention

[0012] This summary describes certain aspects of the embodiments described herein to provide a basic understanding. This summary is not a broad overview of the inventive subject matter and is not intended to identify key or essential elements or to delineate the scope of the inventive subject matter. In some embodiments, a cable length-constant medical device includes a path length adjustment drive mechanism, which may be located in the rear end of the medical device and can eliminate the need for inherent length constancy of the distal cable path. This drive mechanism may particularly include a mechanism that autonomously alters the rear-end cable routing to compensate for changes in distal path length, thereby providing path length constancy throughout the medical device. As a result, the combination of the drive mechanism and the wrist allows for simple winch actuation, and an external control system does not need to actively monitor or adjust cable length tension. In some embodiments, tension changes caused by a lack of length constancy in a portion of the device actuate the path-changing mechanism to compensate for the remote lack of length constancy, for example, causing the path length of one pair of cables to increase in response to a decrease in tension of the path length of another pair of cables.

[0013] In some embodiments, an apparatus includes a wrist assembly, an end effector, a cable pair, and a drive mechanism. The wrist assembly has a proximal wrist portion and a distal wrist portion. The proximal wrist portion is coupled to a distal portion of a shaft. Actuation of the wrist assembly produces movement of the distal wrist portion relative to the proximal wrist portion. The wrist assembly defines a wrist cable path of varying length as the distal wrist portion moves relative to the proximal wrist portion. The end effector is coupled to the distal wrist portion. Actuation of the end effector produces movement of the end effector relative to the distal wrist portion. The cable pair is routed through the wrist cable path, and a first end of the cable pair is coupled to the end effector. The drive mechanism is coupled to the proximal portion of the shaft and is capable of moving a second end of the cable pair to actuate the end effector. The second end of the cable pair is routed through a drive cable path within the drive mechanism. The drive mechanism includes an adjustment mechanism configured to change the length of the drive cable path in response to a change in the length of the wrist cable path.

[0014] In some embodiments, a device includes a wrist assembly, an end effector, a cable pair, and a drive mechanism. The wrist assembly has a proximal wrist portion and a distal wrist portion. The proximal wrist portion is coupled to a distal portion of a shaft. Actuation of the wrist assembly produces movement of the distal wrist portion relative to the proximal wrist portion. The end effector is coupled to the distal wrist portion. Actuation of the end effector produces movement of the end effector relative to the distal wrist portion. The cable pair has a first end and a second end, the first end being coupled to the end effector. The drive mechanism is coupled to the proximal portion of the shaft and is capable of moving the second end of the cable pair to actuate the end effector. The second end of the cable pair is wired through a drive cable path within the drive mechanism. The drive mechanism includes an adjustment mechanism having an input portion that receives a force applied by the second end of the cable pair. The adjustment mechanism is configured to change the length of the drive cable path in response to a change in the force applied by the second end of the cable pair. Attached Figure Description

[0015] Figures 1A and 1B show schematic side and top views of prior art medical devices employing constant cable length wiring.

[0016] Figure 1C shows a schematic side view of the medical device of Figure 1A when the distal portion of the wrist rotates about the pitch axis.

[0017] Figure 2A and Figure 2B A side view of a medical device according to one embodiment is shown, the medical device including a drive mechanism for compensating for distal cable routing with non-constant cable length.

[0018] Figure 2C It can be shown that it can be included Figure 2A and Figure 2B A perspective view of the wrist in a medical device.

[0019] Figure 3 A perspective view is shown of a path length compensation drive mechanism for a pair of actuation cables according to one embodiment.

[0020] Figure 4A A top view of the proximal portion of a medical device having a path length compensation drive mechanism according to one embodiment is shown.

[0021] Figure 4B Show Figure 4A A side view of the proximal portion of a medical device.

[0022] Figure 5 A top view showing an embodiment of a medical device having a path length compensation drive mechanism using a sliding shuttle, according to one embodiment.

[0023] Figure 6A top view is shown of a path length compensation drive mechanism using a lever linkage device between movable winches according to one embodiment.

[0024] Figure 7 This is a perspective view of an apparatus according to one embodiment.

[0025] Figure 8 It is by Figure 7 The area Z shown is an enlarged perspective view of the transmission mechanism at the proximal portion of the device.

[0026] Figure 9 yes Figure 8 A perspective view of the transmission device shown.

[0027] Figure 10 According to one embodiment Figure 8 The exploded perspective view of the transmission device shown illustrates the adjustment mechanism.

[0028] Figure 11 and Figure 12 yes Figure 10 Front perspective view of the adjustment mechanism shown Figure 11 ) and left perspective ( Figure 12 ).

[0029] Figure 13 yes Figure 10 An exploded perspective view of the adjustment mechanism shown.

[0030] Figure 14 yes Figure 10 A perspective view of the movable component of the adjustment mechanism shown.

[0031] Figure 15 It is in the first configuration Figure 10 The top view of the adjustment mechanism shown.

[0032] Figure 16 It is in the first configuration Figure 10 A cross-sectional view of a portion of the adjustment mechanism shown, the cross-section being along... Figure 14 It is cut from line X16-X16 in the middle.

[0033] Figure 17 It is in the first configuration Figure 10 A cross-sectional view of a portion of the adjustment mechanism shown, the cross-section being along... Figure 14 It is taken from line X17-X17 in the middle.

[0034] Figures 18-19 It is in the second configuration ( Figure 18 ) and third configuration ( Figure 19 )of Figure 10 The top view of the adjustment mechanism shown. Detailed Implementation

[0035] The embodiments described herein advantageously maintain the cable length for pitch and yaw movements of the wrist assembly by allowing variations in cable path length in the wrist and autonomously applying compensated variations in cable path length in the device actuator (e.g., located proximally in the device). This arrangement facilitates improved device performance in smaller devices. In such applications, the size of the wrist may not allow sufficient space for an inherently long, constant path for all cables traversing the wrist; therefore, the embodiments described herein include a route-changing mechanism that alters the cable routing in the actuator (or rear end) to at least approximately maintain the total cable length from the actuator actuator (e.g., drive winch) to the driven mechanism (e.g., end effector). For example, medical devices lacking space for the yaw actuation cable to cross the pitch axis of the wrist may include a drive mechanism of the type shown and described herein that compensates for the lack of constant cable length in the wrist.

[0036] In some embodiments, the wrist assembly can route cables (e.g., yaw actuation cables of an actuated end effector) through the joint and offset them relative to the joint's axis of rotation. As a result, when the wrist assembly rotates about the joint (e.g., pitch rotation), the cable path length increases on one side of the axis of rotation, which tends to stretch some cables or increase tension in some cables, while the cable path length decreases on the opposite side of the axis of rotation, which allows some cables to slack off or reduce tension in some cables. In these embodiments, the adjustment mechanism described herein can maintain the tension in the cables within a suitable range during rotation by adjusting the tension in the proximal portion of the device or the cable path length. This prevents slack cables from derailing and prevents taut cables from deforming or damaging other components.

[0037] In some embodiments, an apparatus includes a wrist assembly, an end effector, a cable pair, and a drive mechanism. The wrist assembly has a proximal wrist portion and a distal wrist portion. The proximal wrist portion is coupled to a distal portion of a shaft. Actuation of the wrist assembly produces movement of the distal wrist portion relative to the proximal wrist portion. The wrist assembly defines a wrist cable path having a length that changes as the distal wrist portion moves relative to the proximal wrist portion. The end effector is coupled to the distal wrist portion. Actuation of the end effector produces movement of the end effector relative to the distal wrist portion. The cable pair is routed through the wrist cable path, and a first end of the cable pair is coupled to the end effector. The drive mechanism is coupled to the proximal portion of the shaft and is capable of moving a second end of the cable pair to actuate the end effector. The second end of the cable pair is routed through a drive cable path within the drive mechanism. The drive mechanism includes an adjustment mechanism configured to change the length of the drive cable path in response to a change in the length of the wrist cable path.

[0038] In some embodiments, a device includes a wrist assembly, an end effector, a cable pair, and a drive mechanism. The wrist assembly has a proximal wrist portion and a distal wrist portion. The proximal wrist portion is coupled to a distal portion of a shaft. Actuation of the wrist assembly produces movement of the distal wrist portion relative to the proximal wrist portion. The end effector is coupled to the distal wrist portion. Actuation of the end effector produces movement of the end effector relative to the distal wrist portion. The cable pair has a first end and a second end, the first end being coupled to the end effector. The drive mechanism is coupled to the proximal portion of the shaft and is capable of moving the second end of the cable pair to actuate the end effector. The second end of the cable pair is wired through a drive cable path within the drive mechanism. The drive mechanism includes an adjustment mechanism having an input portion that receives a force applied by the second end of the cable pair. The adjustment mechanism is configured to change the length of the drive cable path in response to a change in the force applied by the second end of the cable pair.

[0039] In some embodiments, an apparatus includes a wrist assembly, an end effector, a cable pair, a drive mechanism, and an adjustment tool. The wrist assembly has a proximal wrist portion and a distal wrist portion. The proximal wrist portion is coupled to a distal portion of a shaft. Actuation of the wrist assembly produces movement of the distal wrist portion relative to the proximal wrist portion. The wrist assembly defines a wrist cable path having a length that changes as the distal wrist portion moves relative to the proximal wrist portion. The end effector is coupled to the distal wrist portion. Actuation of the end effector produces movement of the end effector relative to the distal wrist portion. The cable pair is routed through the wrist cable path and has a first end coupled to the end effector. The drive mechanism is coupled to the proximal portion of the shaft and includes an actuator that moves a second end of the cable pair to actuate the end effector. The second end of the cable pair is routed through a drive cable path within the drive mechanism. The adjustment tool is configured to change the length of the drive cable path in response to a change in the length of the wrist cable path.

[0040] In some embodiments, a medical device includes a drive mechanism, a shaft extending from the drive mechanism, and a driven mechanism on the shaft. A pair of cables have routes in the driven mechanism and through the shaft to the drive mechanism, and actuation of the degrees of freedom of the driven mechanism causes a change in the path length of the pair of cables outside the drive mechanism. The drive mechanism includes a route-changing mechanism that engages with the pair of cables, and during actuation, the route-changing mechanism autonomously changes the path length of the first pair of cables in the drive mechanism to compensate for the change in the path length of the first pair of cables in the driven mechanism.

[0041] In some embodiments, a medical device includes a transmission, a shaft extending from the transmission, and a drive mechanism within the transmission. A first pair of cables extends from the transmission through the shaft to a driven mechanism and is coupled to actuate a first degree of freedom of the driven mechanism. A second pair of cables extends from the transmission through the shaft to an actuating mechanism. The second pair of cables is coupled to actuate a second degree of freedom of the driven mechanism. The drive mechanism is coupled to the first and second pairs of cables and includes a path-changing mechanism that actuates the mechanism in response to tension variations caused by a lack of constant length in the paths of the first and second pairs of cables through the shaft.

[0042] In some embodiments, a device includes a chassis, a cable pair, an actuator, and an adjustment mechanism. The chassis is coupled to a proximal portion of a shaft. The distal portion of the shaft is configured to be coupled to a wrist assembly. The cable pair is routed through the shaft and has a first end and a second end. The first end of the cable pair is configured to be coupled to the wrist assembly. The second end of the cable pair is routed through a drive cable path within the chassis. The actuator is located within the chassis and is configured to move the second end of the cable pair. The adjustment mechanism has an input portion that receives a force applied by the second end of the cable pair. The adjustment mechanism is configured to change the length of the drive cable path in response to a change in the force applied by the second end of the cable pair.

[0043] This document also describes a method of manipulating a device. In some embodiments, a method includes actuating a wrist assembly of the device to move a distal wrist portion relative to a proximal wrist portion from a first orientation to a second orientation. The proximal wrist portion is coupled to a distal portion of a shaft. The distal wrist portion is coupled to an end effector. A cable pair is routed through a wrist cable path such that a first end of the cable pair is coupled to the end effector, and a second end of the cable pair is coupled to an actuator within a transmission (also referred to as a rear end). This transmission is coupled to the proximal portion of the shaft. As the distal wrist portion moves from the first orientation to the second orientation, the length of the wrist cable path changes. The length of the transmission cable path through which the second end of the cable pair is routed changes in response to the change in the length of the wrist cable path. The second end of the cable pair is moved via the actuator within the transmission to actuate the end effector.

[0044] As used herein, when used with reference numerals, the term "about" means the reference numeral plus or minus up to 10% of that reference numeral. For example, the term "about 50" covers a range of 45 to 55. Similarly, the term "about 5" covers a range of 4.5 to 5.5.

[0045] As used in this specification, the term "distal" refers to the direction toward the working site, while the term "proximal" refers to the direction away from the working site. Thus, for example, the end of the instrument closest to the target tissue will be the distal end of the tool, while the end opposite the distal end (i.e., the end manipulated by the user) will be the proximal end of the instrument.

[0046] Furthermore, the specific words chosen to describe one or more embodiments and optional elements or features are not intended to limit the invention. For example, spatially relative terms—such as “below,” “under,” “lower,” “above,” “upper,” “near,” “far”, etc.—are used to describe the relationship between one element or feature and another element or feature as shown in the figures. In addition to the orientations and orientations shown in the figures, these spatially relative terms are also intended to cover different orientations (i.e., translational arrangements) and orientations (i.e., rotational arrangements) of the device in use or operation. For example, if the device in the figures is flipped, an element described as “below” or “under” other elements or features would be described as “above” or “on” other elements or features. Thus, the term “below” can include orientations and orientations above and below. The device can be in other orientations (e.g., rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein are interpreted accordingly. Similarly, descriptions of movement along (translation) and about (rotation) various axes include various spatial device orientations and orientations. The combination of body orientation and orientation defines the body posture.

[0047] Similarly, geometric terms such as “parallel,” “perpendicular,” “circular,” or “square” do not require absolute mathematical precision unless the context otherwise specifies. Instead, such geometric terms allow for variations caused by manufacturing or equivalent functions. For example, if an element is described as “circular” or “generally circular,” elements that are not precisely circular (e.g., elements that are slightly elliptical or polygonal with multiple sides) are still covered by this description.

[0048] Furthermore, the singular forms “a,” “an,” and “the” also include the plural forms, unless the context otherwise requires. The terms “comprising,” “including,” “having,” etc., specifically describe the presence of the stated features, steps, operations, elements, components, etc., but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, or groups.

[0049] Unless otherwise stated, the terms “device,” “medical device,” “instrument,” and their variations are used interchangeably.

[0050] The various aspects of the present invention are primarily described in relation to embodiments using a surgical system, such as the daemon, commercially available from Intuitive Surgical, Inc. of Sunnyvale, California, USA. Surgical systems. An example of such surgical systems is da. Xi TM Surgical system (model IS4000) and da Vinci Surgical system (model IS4000) and da Vinci Surgical system (model IS3000). However, those skilled in the art will understand that the inventive aspects disclosed herein can be embodied and implemented in various ways, including computer-aided embodiments and implementations, non-computer-aided embodiments and implementations, and mixed combinations of manual and computer-aided embodiments and implementations. Regarding da... The embodiments of the surgical systems (e.g., models IS4000, IS3000, IS2000, and IS1200) are presented by way of example only and are not intended to limit the scope of the inventive aspects disclosed herein. Where applicable, inventive aspects can be embodied and implemented in relatively small handheld manual operating devices and relatively large systems with additional mechanical supports.

[0051] Figure 2A and Figure 2B A schematic side view of a medical device 200 for use in minimally invasive medical procedures is shown. The medical device 200 includes a wrist 230, which includes a pitch joint 240 through which a first pair of actuation cables 222a and 222b and a second pair of actuation cables 224a and 224b extend. (Cables 222b and 224b are in...) Figure 2A and Figure 2B Not visible in the side view, but Figure 2C(The wrist 230 shown is visible in the perspective view.) In the illustrated configuration, the pitch joint 240 is formed by a proximal link (or proximal wrist portion) 242 and a distal link (or distal wrist portion) 244, which are mechanically connected or arranged to allow rotation about the pitch axis 246. The term "pitch" is arbitrary and is used herein to refer to the movement of the distal link 244 relative to the proximal link 242. The pitch joint 240 may alternatively employ many types of joint structures, such as using pins, rolling surfaces, or flexures. A pair of actuation cables 226a and 226b attached to the link 244 extend from the link 244 in the joint 240 through the spindle 220 of the instrument 200 to the drive mechanism 210 of the instrument 200. Each cable 222a, 222b, 224a, 224b, 226a, and 226b may include a section of stranded cable, conductor, strip, tape, tube, rod, or similar elongated structure. In some embodiments, each cable includes a section of stranded cable crimped onto a hyaluronic acid tube, the stranded cable being used where the cable undergoes significant bending or tangling, and the hyaluronic acid tube being used in other sections to limit the cable's stretch. More generally, the term "cable" is used herein to refer to any tendon or tendon-like structure that can be pulled to actuate a mechanism.

[0052] The drive mechanism 210 can be configured to engage with a robot to move cables, resulting in rotation of the distal link 244 relative to the proximal link 242 and movement of the end effector 258 relative to the distal link 244. Movement of the end effector 258 and rotation of grippers 252 and 254, which are together or opposed to each other (e.g., as grippers), can occur about a yaw axis (the term "yaw" is arbitrary). Thus, the drive mechanism 210 can move the proximal end of any combination of cables to produce desired movement via any suitable mechanism. In some embodiments, the drive mechanism 210 (and any drive mechanism described herein) may include a winch or other motor-driven roller that rotates or "wraps" the cable to produce movement. For example, in some embodiments, the drive mechanism 210 may include any end-end assembly or component described in U.S. Patent No. 9,204,923 entitled "Medical Instrument ElectronicallyEnergized Using Drive Cables," the entire contents of which are incorporated herein by reference.

[0053] For pitch actuation (i.e., rotation of the distal link 244 about the pitch axis 246), the transmission 210 may include a conventional drive mechanism (not shown, also referred to as an actuator) powered by a motor. In particular, the robot can operate the conventional drive mechanism in the transmission 210 to wind up one cable 226a or 226b and release another cable 226b or 226a, thereby rotating the distal link 244 relative to the proximal link 242. Figure 2A The medical device 200 is shown in a first (or unbent) configuration, and Figure 2B The medical device 200 is shown in a second configuration, wherein the length of cable 226b has been released and the length of cable 226a has been pulled in to cause the distal link 244 (and the more distal portion of the medical device 200) to rotate about the pitch axis 246 relative to the proximal link 242.

[0054] Cables 222a and 222b passing through joint 240 are used to actuate gripper 252, for example, to rotate gripper 252 about a yaw axis corresponding to pivot 256. Cables 224a and 224b are used to actuate gripper 254, for example, to rotate gripper 254 about a yaw axis corresponding to pivot 256. As shown, joint 240 does not include a cable path that allows cables 222a, 222b, 224a, and 224b to pass through joint 240 along a continuous path of cable length. Similarly, joint 240 does not define a cable path through pitch axis 246. For example, as Figure 2C As shown, links 242 and 244 may require space for a central lumen 247, which passes through links 242 and 244 for use in flushing, pressurizing, or other medical systems (not shown), such as visual systems. Therefore, cables 222a and 222b do not cross the axis of rotation 246 of joint 240. Instead, as shown, cables 222a and 222b pass through the pitch joint 240 offset to one side of the axis of rotation 246, while cables 224a and 224b similarly pass through the pitch joint 240 offset to the opposite side of the axis 246. In some embodiments, the offset distance of cables 222a and 222b from the axis of rotation of joint 240 is the same as the offset distance of cables 224a and 224b from the axis of rotation of joint 240.

[0055] Each pair of cables 222a and 222b or 224a and 224b can be preloaded with tension to reduce the possibility of slack development within the cables, thereby keeping cables 222a, 222b, 224a, and 224b engaged with guide pulleys (not shown) or grippers 252 or 254. For example, when device 200 is in Figure 2AIn the first configuration shown, cables 222a, 222b, 224a, and 224b can all have equal tension. For example... Figure 2A As shown, wrist 230 defines a first wrist cable path 222' through which cables 222a and 222b are routed between the distal link 244 and the proximal link 242. When device 200 is in a first configuration, the first wrist cable path has a length L1. Wrist 230 defines a second wrist cable path 224' through which cables 224a and 224b are routed between the distal link 244 and the proximal link 242. When device 200 is in the first configuration, the second wrist cable path has a length L2. Although shown as a symmetrical embodiment where lengths L1 and L2 are equal when device 200 is in the first configuration, in other embodiments, lengths L1 and L2 may not be equal in the first (or any other) configuration.

[0056] When joint 240 is actuated to rotate distal link 244 relative to proximal link 242, such as Figure 2B As shown, the rotation of joint 240 and the offset characteristics of the first cable path 222' and the second cable path 224' cause a change in the length of the cable paths (and they become unequal). Specifically, in the second (or rotational) configuration, the first cable path 222' has a length L'1 that is less than the length L1. The reduced path length tends to reduce tension and create slack in the cable pair 222a and 222b. Similarly, in the second (or rotational) configuration, the second cable path 224' has a length L'2 that is greater than the length L2. The increased path length tends to increase tension and stretch the cable pair 224a and 224b.

[0057] To minimize cable slack or deformation of cables 222a, 222b, 224a, and 224b during movement of joint 240, transmission 210 includes a path length compensation drive mechanism 212 capable of automatically compensating for changes in cable path length within pitch joint 240. In some embodiments, the path length compensation drive mechanism 212 may change the length of the cable path (i.e., the transmission cable path) within transmission 210 in response to changes in the length of the corresponding wrist cable path. For example, in some embodiments, the path length compensation drive mechanism 212 may change the length of the cable path within transmission 210 in response to a decrease in the path length indicated by L'1, through which cable pairs 222a and 222b are routed. In this way, the total cable path length (from transmission 210 and through joint 240) remains substantially constant (i.e., the path length is held constant). In some embodiments, the path length compensation drive mechanism 212 may change the length of the cable path (i.e., the transmission cable path) within transmission 210 in response to changes in the force applied by the cables. For example, in some embodiments, the path length compensation drive mechanism 212 may change the length of the cable path within the transmission device 210 in response to a decrease in the tension applied to the drive mechanism 212 by the cable pairs 222a and 222b, wherein the cable pairs 222a and 222b are wired through the cable path.

[0058] In some embodiments, the transmission may include an adjustment mechanism that compensates for variations in the path length of a pair of cables within the wrist or joint assembly by moving the orientation of the actuator within the transmission. For example, in some embodiments, the transmission (e.g., transmission 210) may include a winch around which the cable pair is wound, and the adjustment mechanism may change the axis of rotation of the winch to alter the length of the cable path within the transmission. Figure 3 A drive mechanism 300 is shown, which can be used in an instrument transmission to drive a pair of cables 222a and 222b with distal wires having non-constant cable lengths. The drive mechanism 300 includes an input spindle 310 rotatably mounted in a fixed position on a chassis 330 within the instrument transmission. The position of the spindle 310 can be fixed according to the position of an external actuator (e.g., a drive motor (not shown) for a docking port in a medical device). For example, a control robot (not shown) may have docking ports accommodating interchangeable medical devices, and the transmission for each interchangeable medical device may be shaped to fit the docking port, potentially requiring one or more input spindles to be fixed in positions corresponding to the drive motor in the docking port. Therefore, the specifications of the robot's docking port can define the size, shape, and position of the spindle 310 on the chassis 330.

[0059] The drive mechanism 300 includes at least one winch 320 around which cables 222a and 222b are wound. The drive mechanism also includes a mounting member 340 that allows movement of the winch 320. Adjustment of the winch orientation can be used to adjust the length of the cable path within the drive mechanism. Adjustment of the winch orientation can also maintain the tension in cables 222a and 222b at a constant or within a desired operating range. The winch 320 may be a cylindrical winch mounted on an axle 322. Figure 3 As shown, the mounting member 340 includes one or more arm-shaped members, each attached to rotate about a fixed axle 312 of the spindle 310, and these arm-shaped members support the winch axle 322 at a fixed distance from the spindle axle 312. In use, the position of the winch axle 322 can move along a circular path about the spindle axle 312. Furthermore, the drive mechanism 300 includes an adjustment mechanism comprising the mounting member 340 and a spring system 342. The spring system 342 biases the winch 320 and the mounting member 340 to pull or push against the tension applied to the winch 320 by the cables 222a and 222b. In this way, the drive mechanism 300 (and the adjustment mechanism therein) is used to maintain or limit the tension in the cables 222a and 222b. Specifically, the spring system can apply a force to the winch 320 against the force applied to the winch 320 by the cables 222a and 222b.

[0060] Figure 3 One embodiment is shown in which the spring system 342 is a spring with one end fixed to the chassis 330 and the other end coupled to the mounting member 340 or the axle 322. However, other embodiments may include any suitable spring system configuration or biasing system to resist tension in the cables 222a and 222b. For example, in some embodiments, the spring may be stretched or compressed to apply force to the mounting member 340 or the axle 322. Furthermore, many types of springs may be employed, such as helical springs or flexural springs. The spring system may also function as a Hooke's Law spring, which allows the preload tension in the cables 222a and 222b to vary with the orientation of the axle 322, or as a constant force spring, which maintains a constant average tension in the cables 222a and 222b. In some embodiments, the spring system may be incorporated into an arm-shaped member of the mounting member 340, for example, the arm-shaped member may be fixed to the spindle axle 312 and may be bent to provide both movement of the axle 322 and spring force to resist tension in the cables 222a and 222b.

[0061] The drive mechanism 340 includes a drive coupling 350 between the winch 320 and the spindle 310, which connects the winch 320 to rotate as the spindle 310 rotates. Although the drive coupling 350 is shown as a strip, in other embodiments, any suitable coupling may be used to link the rotation of the spindle 310 about the axle 312 to cause the winch 320 to rotate about the axle 322 at any position or a series of positions of the axle 322. For example, in some embodiments, the drive coupling 350 may include a cable, chain drive, or gear system.

[0062] As shown in the figure, the cable pair (i.e., cables 222a and 222b) is wound on a winch 320 such that rotation of the winch 320 about axle 322 releases a certain length of one of cables 222a or 222b while simultaneously winding up an equal length of the other cable 222b or 222a. During operation, if the pitch movement of the wrist joint or other system along the main instrument axis cannot maintain the cable lengths of cables 222a and 222b within the wrist joint, mounting 340, the drive mechanism 300 can move the winch 320 without external intervention to compensate for changes in cable length caused by rotation of the device about a pitch axis (e.g., pitch axis 246). Specifically, as the path length of the cable pair 222a, 222b decreases within the wrist joint, spring 342 pulls axle 322 back (as indicated by arrow AA) to fill the slack created in the two cables 222a and 222b. Similarly, as the path length of cables 222a and 222b increases within the wrist joint, the increased tension applied to the winch 320 will cause the winch 320 to move forward in cables 222a and 222b where the tension might otherwise be potentially destructive (as indicated by arrow BB). Specifically, the spring system 342 maintains constant or desired tension in cables 222a and 222b by compensating for changes in path length within the wrist assembly, such that rotation of the fixed spindle 310 at any orientation of the axle 322 and during movement of the axle 322 can cause rotation of the winch 320, thereby dynamically coupling the driven mechanism of cables 222a and 222b.

[0063] In some operations, the change in cable path length caused by pitch actuation can occur simultaneously with yaw or grip actuation. The term "grip actuation" here broadly refers to the opening or closing of a pair of grippers (e.g., grippers 252 and 254), for example, gripping or releasing an object if the grippers are used as tweezers or a cauterizing tool, or cutting if the grippers are used as scissors. For grip actuation using two pairs of cables (i.e., one pair of cables per gripper), one cable in each pair typically has low tension, while the other cable in the pair typically has high tension to close or hold the grippers. By using a separate spring-loaded path-changing mechanism for each cable pair, the high tension in one cable may resist the spring force attempting to compensate for the length change, and thus may disrupt the function of the path-changing system. Therefore, in some embodiments, the adjustment mechanism can maintain the path length in both pairs of cables and can balance the high clamping tension that may occur in one cable of one pair with the accompanying high clamping tension in one cable of the other pair. Adjustment mechanisms that maintain a constant path length in two pairs of cables are particularly useful in systems with joints or distal mechanisms that cause complementary changes in path length. For example, Figure 2C The wrist 230 routes a pair of cables 222a and 222b to one side of the pitch axis 246 with a certain offset, and routes cables 224a and 224b to the opposite side of the pitch axis 246 with the same offset. As a result, pitch movement causes an increase in the cable path length of one cable pair 222a and 222b or 224a and 224b within the wrist by an amount equal to a decrease in the cable path length of the other cable pair 224a and 224b or cable pair 222a and 222b within the wrist. Therefore, the cable length-constant drive mechanism may include an adjustment mechanism that simultaneously causes complementary displacement of the cable routes in the drivetrain to compensate for further changes in path length.

[0064] In some embodiments, for example, the adjustment mechanism may be located within the drive mechanism of the device and may adjust the drive cable path lengths of multiple cable pairs (i.e., the lengths of the cable pairs routed within the drive mechanism). For example, in some embodiments, the adjustment mechanism may receive input from two or more cable pairs to simultaneously increase the drive cable path of one cable pair while decreasing the drive cable path of another cable pair. For example, in some embodiments, the medical device may include an adjustment mechanism with a pivot arm (or pendulum) located within the drive mechanism of the device and balancing the tension in opposing cable pairs. For example, Figure 4A and Figure 4B The diagram shows a plan view and a sectional side view of a portion of a medical device 400, which has a transmission mechanism 410 from which a main device shaft 420 extends. The device includes a wrist (not shown, but may be similar). Figure 2C The wrist (230) or any other driven mechanism causes the path length changes of the first cable pairs 222a and 222b to be opposite to the path length changes of the second cable pairs 224a and 224b. The wrist may be coupled to the distal end of the spindle 420.

[0065] The drive unit 410 includes four input spindles 412, 414, 416, and 418, which are positioned on the chassis of the drive unit 410 as needed to interface with actuators in a docking port controlling the robot. Input spindles 412 and 414 correspond to the furthest degree of freedom of the medical device 400, such as yaw movement of a pair of grippers (not shown, but similar to grippers 252, 254). Spindle 416 corresponds to one degree of freedom of motion of the wrist joint (e.g., pitch movement), which, as described herein, can cause a change in path length at a location outside the drive unit 410. Specifically, actuation of cable pairs 226a and 226b by spindle 416 can produce a change in the length of the wrist cable path for cable pairs 222a and 222b and cable pairs 224a and 224b. Spindle 418 can correspond to another degree of freedom of motion of the medical device 400, such as axial rotation of the spindle 420. As described herein, the device 400 does not include input from an external control device (e.g., a robot control unit) to dynamically control the cable path length, because path length compensation occurs autonomously within the drive unit 410 via an adjustment mechanism 450. Specifically, as described, the adjustment mechanism 450 responds to tension changes that occur when the distal portion of the medical device 400 (e.g., the wrist assembly) fails to maintain the cable length. This autonomous compensation allows the medical device 400 to maintain the entire cable length (i.e., the total cable length from the drive unit 410 to the distal end of the device) by adjusting the length of the drive cable path.

[0066] The winches on spindles 412, 414, and 416 can be simple cylindrical winches with a circular cross-section around which the cables are wound. In some embodiments, cables 226a and 226b are wound in opposite directions around one or more winches mounted on the axle of spindle 416. A fixed idler pulley 436 redirects cables 226a and 226b back into spindle 420. From there, cables 226a and 226b can be connected to, for example... Figure 2CThe pitch joint is of the type shown. Cables 222a and 222b are wound in opposite directions around one or more winches mounted on the axle of spindle 412, and from there they are routed around a fixed idler pulley 432, a movable pulley 442 on the pivot arm 440, and then around a fixed idler pulley 436, which redirects cables 222a and 222b back into the spindle 420. After extending from the drive unit 410, cables 222a and 222b can travel along a non-constant cable length route, such as across the pitch joint (similar to...). Figures 2A-2C The wrist cable path (as shown) is then connected to the driven mechanism (e.g., Figure 2C (The gripper 252). Similarly, cables 224a and 224b are wound in opposite directions around one or more winches mounted on the axle of spindle 414, and from there routed around a fixed idler 434, a movable pulley 444 on pivot arm 440, and then around a fixed idler 436, which redirects cables 224a and 224b back into spindle 420. After extending from drive unit 410, cables 224a and 224b can travel along non-constant cable length routes, such as across a traverse pitch joint (similar to...). Figure 2A-2C The wrist cable path (as shown) is then connected to another driven mechanism (e.g., Figure 2C (gripper 254).

[0067] The adjustment mechanism 450 includes a pivot arm 440 that is freely rotatable about a pivot 446 fixed to the chassis of the transmission 410. In use, the angular orientation of the pivot arm 440 can be shifted during pitch movements to maintain the desired tension in cable pairs 222a and 222b and cable pairs 224a and 224b without external control of releasing or winding cable lengths from drive winches on spindles 412 and 414. For example, if the pitch movement tends to remotely (i.e., within the wrist) decrease the cable path length and thus decrease the tension in the first cable pairs 222a and 222b, while simultaneously tending to remotely (i.e., within the wrist) increase the cable path length and thus increase the tension in the second cable pairs 224a and 224b, the increased tension in the cable pairs 224a and 224b drives the pendulum 440 to rotate about the pivot 446 and decrease the cable path lengths of the cable pairs 224a and 224b within the transmission 410. The rotation of the pendulum 440 simultaneously increases the cable path lengths for the first cable pairs 222a and 222b within the transmission 410. Similarly, if the pitch motion tends to remotely decrease the cable path lengths and reduce the tension in cable pairs 224a and 224b (i.e., causing slack) and tends to remotely increase the cable path lengths and increase the tension in cable pairs 222a and 222b, the increased tension causes the pendulum 440 to rotate in the opposite direction about the pivot 446 to decrease the cable path lengths for cable pairs 222a and 222b within the transmission 410 and increase the cable path lengths for cable pairs 224a and 224b within the transmission 410. Therefore, the device 400 has a cable length-constant drive mechanism within the transmission 410 that compensates for the opposite changes in the distal cable path lengths of the two cable pairs.

[0068] In other embodiments, a cable-length-constant medical device may include an adjustment mechanism using a linear shuttle that shifts from one side to the other to alter the transmission cable paths of two pairs of cables in the medical device's drivetrain. For example, Figure 5 A medical device 500 is shown, which includes a transmission 510, a main shaft 420 extending from the transmission 510, and a wrist 230 at the distal end of the main shaft 420. The wrist 230 may include, as shown in the reference above... Figure 2A , Figure 2B and Figure 2C The aforementioned structures are actuated using three pairs of actuation cables as described above (e.g., cables 222a and 222b for actuating the yaw movement of one gripper, cables 224a and 224b for actuating the yaw movement of the second gripper, and cables 226a and 226b for actuating the pitch of the wrist joint).

[0069] The instrument transmission device 510 is similar to Figure 4A and Figure 4BThe transmission device 410 specifically includes the input spindles 412, 414, 416, and 418 as described above, and fixed idler pulleys 432, 434, and 436. The transmission device 510 differs from transmission device 410 in that it includes an adjustment mechanism 540 implemented using a sliding system comprising pulleys 542 and 544 mounted on a shuttle 546, which slides on a guide or track 548. As shown, the device 500 includes cables 222a and 222b wound in opposite directions around one or more winches mounted on spindle 412. The transmission cable paths for cables 222a and 222b are further defined by routes around the fixed idler pulley 432, the movable pulley 542 on the shuttle 546, and the fixed idler pulley 436. Cables 224a and 224b are similarly wound in opposite directions around one or more winches mounted on spindle 414. The drive cable paths for cable pairs 224a and 224b are further defined by routes surrounding a fixed idler wheel 434, a movable pulley 544 on the shuttle 546, and a fixed idler wheel 466. During the pitch movement of the wrist 230, the cable path length of one pair of cables 222a and 222b or 224a and 224b within the wrist 230 increases, while the cable path length of the other pair of cables 224a and 224b or 222a and 222b decreases. In response to the change in cable path length in the wrist 230 and the resulting change in cable tension, the shuttle 546 slides to alter the drive cable path lengths of cables 222a, 222b, 224a, and 224b, thereby compensating for the wrist cable path length variation within the wrist 230. In this way, the adjustment mechanism can at least approximately maintain the entire cable path length.

[0070] Figure 6 A medical device 600 is shown, including a drive mechanism 610 having another path length compensation drive mechanism that compensates for opposite path length variations in two pairs of cables for actuating yaw degrees of freedom. In the device 600, each pair of cables 222a and 222b or 224a and 224b for actuating yaw or gripping rotation has a winch 320 with a rotatable mount 340, which may be similar to the one described above. Figure 3 The structure described above. Specifically, each winch 320 is rotatable on axle 322, and each mounting member 340 is rotatable in an arc about axle 312 of its associated drive spindle 310. A drive coupling 350 connects the drive spindle 310 to the corresponding winch 320 such that, regardless of the orientation of axle 322, each winch 320 rotates about its axle 322 in response to the rotation of its associated drive spindle 310 about its axle 312.

[0071] Reference Figure 3Compared to the described system, the mounting member 340 in device 600 is not coupled to the spring system. Instead, a rigid rod 640 couples the two winch axles 322. The mounting member 340 still allows each axle 322 to rotate about its associated spindle axle 312, but the connecting rod 640 connects the axles 322 such that when one axle 322 rotates about its associated spindle 312, the connecting rod 640 causes the other axle 322 to rotate about its associated spindle 312. Furthermore, the connecting rod 640 and the mounting member 340 have selected lengths and orientations such that rotation that shortens the cable path length of a pair of cables 222a and 222b or 224a and 224b in the transmission 610 simultaneously lengthens the path length of another pair of cables 224a and 224b or 222a and 222b in the transmission 610. The fixed spacing of the spindle wheel 312 on the chassis of the transmission device 610, the two mounting pieces 340, and the connecting rod 630 forms a four-bar linkage, essentially a four-bar pendulum, functioning similarly to the pivot arm or sliding system described above. The device 600 can have the advantage of requiring relatively few idler wheels 630 to route cables 222a, 222b, 224a, and 224b to the spindle 620. Cables 222a, 222b, 224a, and 224b can act as springs, because the lack of a constant cable length on the distal side, which causes an increase in cable tension in one cable pair and a decrease in tension in the other, will directly and automatically actuate the route-changing mechanism to compensate for the lack of constant cable length. Therefore, Figure 6 The adjustment mechanism shown does not require external control.

[0072] Figures 7-19These are various views of an instrument 1400 according to one embodiment. In some embodiments, the instrument 1400, or any component thereof, may optionally be part of a surgical assembly for performing minimally invasive surgery, and may include a patient-side remote manipulator unit, one or more motion linkage devices, one or more cannulas, etc. The instrument 1400 includes a drive mechanism 1700 (also referred to as a rear-end mechanism), a shaft 1410, a wrist assembly 1500, and an end effector 1460. The wrist assembly 1500 may be similar to any wrist assembly shown and described herein. The end effector 1460 may include any suitable tooling component and may be similar to any end effector described herein. The shaft 1410 may be any suitable elongated shaft coupling the wrist assembly 1500 to the drive mechanism 1700. Specifically, shaft 1410 includes a proximal portion 1411 and a distal portion 7412. The proximal portion 1411 is coupled to the housing 1760 of the drive unit 1700, and the distal portion 7412 is coupled to the wrist assembly 1500 (e.g., a proximal link of the wrist assembly 1500, similar to link 242 described above). Shaft 7410 defines one or more channels through which cables (described below) and other components (e.g., wires, ground wires, etc.) can be routed from the drive unit 1700 to the wrist assembly 1500.

[0073] The device 1400 includes a cable coupling a transmission 1700 to a wrist assembly 1500 and an end effector 1460. The device 1400 is configured such that movement of the cable can produce rotation of the wrist assembly 1500 about a joint axis (e.g., similar to the pitch axis 246 described above), rotation of the end effector 1460 about a rotation axis (e.g., similar to axis 256 described above, also referred to as the yaw axis), gripping rotation of the tool component of the end effector 1460 about the yaw axis, or any combination of these movements. Changes in the pitch, yaw, or grip of the device 1400 can be performed by manipulating the cable within the transmission 1700. Specifically, see reference... Figure 8 , Figure 10 and Figures 15-17 The device 1400 includes a first cable pair 1420 and a second cable pair 1430. The first cable pair 1420 includes cables 1420A and 1420B and has a first end (not shown) coupled to and actuating a tool member of an end effector 1460 (similar to the arrangement of cable pair 222 actuating tool member 252 shown above). The first cable pair 1420 is wired from the end effector 1460 through the wrist assembly 1500 and the shaft 1410, such that a second end 1421 of the first cable pair 1420 is located within the transmission 1700 (see [link to original document]). Figure 8 and Figure 10In this manner, the transmission 1700 can move the second end 1421 of the first cable pair 1420 to actuate the end effector 1460. The second cable pair 1430 includes cables 1430A and 1430B and has a first end (not shown) coupled to and actuating the tool member of the end effector 1460 (similar to the arrangement of the cable pair 224 actuating the tool member 254 shown above). The second cable pair 1430 is routed from the end effector 1460 through the wrist assembly 1500 and the shaft 1410, such that the second end 1431 of the second cable pair 1430 is within the transmission 1700 (see [link to original text]). Figure 8 and Figure 10 In this way, the transmission device 1700 can move the second end 1421 of the second cable pair 1430 to actuate the end effector 1460.

[0074] In some embodiments, the device 1400 may include a third cable pair (not shown) coupled to and actuating the wrist assembly 1500. For example, this third cable pair may be similar to cable pair 226 as described above and may be used to move the distal link of the wrist assembly 1500 relative to the proximal link of the wrist assembly 1500 (similar to the rotation of the distal link 244 relative to the proximal link 242 as shown and described above). This rotation of the wrist assembly 1500 may be referred to as pitch.

[0075] Similar to the wrist 230 described above, the wrist assembly 1500 may define one or more wrist cable paths through which a first end of the first cable pair 1420 and a first end of the second cable pair 1430 are routed. In some embodiments, the wrist assembly 1500 may define a first wrist cable path (similar to the first wrist cable path 222' described above) through which the first cable pair 1420 is routed and a second wrist cable path (similar to the second wrist cable path 224' described above) through which the second cable pair 1430 is routed. Furthermore, when the wrist assembly 1500 is actuated to produce pitch rotation, the lengths of the wrist cable paths may change (and become unequal). Specifically, when the distal link of the wrist assembly 1500 is rotated in a first direction, the first wrist cable path decreases, which tends to reduce tension and create slack in the first cable pair 1420, and the second wrist cable path increases, which tends to increase tension and may stretch the second cable pair 1430. Conversely, when the distal link of the wrist assembly 1500 is rotated in the second direction, the length of the first wrist cable path increases, which tends to increase tension and may stretch the first cable pair 1420, and the length of the second wrist cable path decreases, which tends to decrease tension and create slack in the second cable pair 1430. As described below, the transmission 1700 includes an adjustment mechanism 1800 that automatically compensates for changes in cable path length occurring in the wrist assembly 1500. In this way, the overall cable path length (from the transmission 1700 through the wrist assembly 1500 to the actuated end effector tool component) remains substantially constant (i.e., the path length is constant).

[0076] The drive mechanism 1700 generates movement in each cable pair to produce the desired movement (pitch, yaw, or grip) at the wrist assembly 1500. Specifically, the drive mechanism 1700 includes components and controls to move some cables in a proximal direction (i.e., pull or "pay in") while allowing distal movement of other cables (i.e., release or "pay out"). For example, proximal movement of cable 1420A and corresponding distal movement of cable 1420B will produce rotation of the tool member (e.g., tool member 252) about the yaw axis. See also Figures 8-10 The transmission device 1700 includes a chassis 1760, a first winch assembly 1710, a second winch assembly 1720, a third winch assembly 1730, and an adjustment mechanism 1800.

[0077] The chassis 1760 provides structural supports for mounting and aligning components of the transmission 1700. For example, the chassis 1760 defines an opening therein for mounting the proximal portion 1411 of the shaft 1410, and multiple openings therein for mounting the winch assembly. The chassis 1760 includes a mounting bracket 1765 that provides additional mounting surfaces and support (e.g., for the winch assembly). Figure 10 As shown, the bracket 1765 includes a pair of mounting portions 1766 (only one of the mounting portions 1766 is shown), which engage with a mounting tab 1812 of the cable adjustment mechanism 1800 to retain the cable adjustment mechanism 1800 within the transmission 1700. In addition to providing mounting support for the internal components of the transmission 1700, the chassis 1760 also includes external features (e.g., recesses, clips, etc.) that interface with a mating port for connection to a drive device (not shown). The drive device may be, for example, a computer-aided remote surgical system that can receive and manipulate instruments 1400 to perform various surgical procedures. In other embodiments, the drive device may be an assembly system that can receive and manipulate instruments 1400 to perform various assembly operations.

[0078] The first winch assembly 1710 includes a shaft that can be driven by a motor to rotate about a winch wheel axle. This rotating shaft includes a portion wound around the second end 1421 of a first cable pair 1420. In this manner, cable 1420A extends tangentially from one side of the first winch assembly 1710, and cable 1420B extends tangentially from the other side of the first winch assembly 1710. Therefore, when the first winch assembly 1710 rotates in a first direction, cable 1420A can move proximally (i.e., can be pulled inward or wound around the rotating shaft), and cable 1420B can move distally (i.e., can be released from or unwound from the rotating shaft). The movement of the cable pair 1420 can be reversed by changing the rotational direction of the first winch assembly 1710. The second winch assembly 1720 includes a shaft that can be driven by a motor to rotate about a winch wheel axle. This rotating shaft includes a portion wound around the second end 1431 of a second cable pair 1430. In this manner, cable 1430A extends tangentially from one side of the second winch assembly 1720, and cable 1430B extends tangentially from the other side of the second winch assembly 1720. Therefore, when the second winch assembly 1730 rotates in the first direction, cable 1430A can move proximally (i.e., it can be pulled inward or wound around the axis of rotation), and cable 1430B can move distally (i.e., it can be released from or unwound from the axis of rotation). By changing the direction of rotation of the first winch assembly 1710, the movement of the second cable 1430 can be reversed.

[0079] Reference Figure 15The arrangement of the first winch assembly 1710 and other components within the transmission 1700 defines a first drive cable path P1 through which the second end 1421 of the first cable pair 1420 is routed. Similarly, the arrangement of the second winch assembly 1720 and other components within the transmission 1700 defines a second drive cable path P2 through which the second end 1431 of the second cable pair 1430 is routed. As described herein, the adjustment mechanism 1800 is configured to change the lengths of the first drive cable path P1 and the second drive cable path P2 in response to changes in the length of the corresponding wrist cable paths. In this way, the overall cable path length of each cable pair (from the transmission 1700 through the wrist assembly 1500 to the actuated end effector tool component) remains substantially constant (i.e., the path length is held constant). This allows the tension within the first cable pair 1420 and the second cable pair 1430 to be maintained within a desired range, regardless of the pitch orientation of the wrist assembly 1500.

[0080] See Figures 11-13 The adjustment mechanism 1800 includes a frame 1810, a first mounting cover 1831, a second mounting cover 1832, and a movable member 1850. The frame 1810 is configured to snap-fit ​​into the chassis 1860 of the transmission device 1700. Specifically, the frame 1810 includes a pair of alignment pins 1813 and a pair of connecting tabs 1812, which engage with the mounting bracket 1765. See also... Figure 10 The connecting tab 1812 is configured to couple to the mounting portion 1766 to hold the adjusting mechanism 1800 in the proper position within the transmission 1700.

[0081] See Figure 13The frame 1810 includes a first idler wheel portion and a second idler wheel portion. The first idler wheel portion includes a pin 1818 and a pair of cable guides 1819. The first idler wheel 1841 is mounted to the pin 1818 on a first side (top side) of the frame 1810 and rotates about the pin 1818. Cable 1420A of the first cable pair 1420 is partially wound around the first idler wheel 1841. The cable guides 1819 have a curved shape corresponding to the shape of the first idler wheel 1841 and hold cable 1420A within the cable groove of the first idler wheel 1841. The second idler wheel 1842 is mounted to the pin 1818 on a second side (bottom side) of the frame 1810 and rotates about the pin 1818. Cable 1420B of the first cable pair 1420 is partially wound around the second idler wheel 1842. A cable guide 1819 (not shown) on the bottom side of frame 1810 has a curved shape corresponding to the shape of the second idler wheel 1842 and holds cable 1420B within the cable groove of the second idler wheel 1842. The second idler wheel portion includes a pin 1821 and a pair of cable guides 1822. A third idler wheel 1843 is mounted to the pin 1821 on the top side of frame 1810 and rotates about the pin 1821. Cable 1430A of the second cable pair 1430 is partially wound around the third idler wheel 1843. The cable guide 1822 has a curved shape corresponding to the shape of the third idler wheel 1843 and holds cable 1430A within the cable groove of the third idler wheel 1843. A fourth idler wheel 1844 is mounted to the pin 1821 on the bottom side of frame 1810 and rotates about the pin 1821. Cable 1430B of the second cable pair 1430 is partially wound around the fourth idler wheel 1844. The cable guide 1822 on the underside of frame 1810 has a curved shape corresponding to the shape of the fourth idler wheel 1844, and holds cable 1430B within the cable groove of the fourth idler wheel 1844. With this arrangement, the idlers define a portion of the first drive cable path P1 and the second drive cable path P2. Although the drive cable path P1 of the first cable pair 1420 comprises two slightly different paths (one for cable 1420A and the other for cable 1420B), for simplicity, the first drive cable path P1 is used to generally refer to the path of each of cables 1420A and 1420B. Similarly, although the drive cable path P2 of the second cable pair 1430 comprises two slightly different paths (one for cable 1430A and the other for cable 1430B), for simplicity, the second drive cable path P2 is used to generally refer to the path of each of cables 1430A and 1430B.

[0082] The end of frame 1810 includes a first pin 1824 and a second pin 1828, with bearings 1845 mounted around the first pin 1824 and the second pin 1828. The centerlines of the first pin 1824 and the second pin 1828 define the axis of rotation for each bearing 1845. Furthermore, as described in detail herein, the centerlines of pins 1824 and 1828 define a linear path along which a movable member 1850 translates to adjust the lengths of the first drive cable path P1 and the second drive cable path P2. Bearings 1845 can be any suitable bearing, such as roller bearings, ball bearings, or tapered roller bearings (i.e., cone bearings). Figure 13 As shown, the end of the frame 1810 also includes a pair of sliding surfaces 1825, 1829, and the corresponding surfaces 1858, 1868 can slide against the sliding surfaces 1825, 1829. The sliding surfaces 1825, 1829 may include a surface coating or treatment to reduce friction between the frame 1810 and the movable member 1850.

[0083] A first mounting cover 1831 is coupled to the frame 1810 and secures the bearing 1845 in place, and also restricts the upward movement of the movable member 1850. Specifically, the first mounting cover 1831 includes a first mounting hole 1833 and a second mounting hole 1835 through which fasteners can be placed to couple the first mounting cover 1831 to the frame 1810, and the second mounting hole 1835 is coupled around a pin 1824. The first mounting cover 1831 includes a stop surface 1836 mounted above a portion of the first fork 1851 of the movable member 1850, thus restricting the upward movement of the movable member 1850. A second mounting cover 1832 is coupled to the frame 1810 and secures the bearing 1845 in place, and also restricts the upward movement of the movable member 1850. Specifically, the second mounting cover 1832 includes a first mounting hole 1837 and a second mounting hole 1839 through which fasteners can be placed to couple the second mounting cover 1832 to the frame 1810, and the second mounting hole 1839 is coupled around the pin 1828. The second mounting cover 1832 includes a stop surface 1840 mounted above a portion of the second fork 1852 of the movable member 1850, thus restricting upward movement of the movable member 1850.

[0084] The movable member 1850 is configured to move relative to the frame 1810 to change the lengths of the first drive cable path P1 and the second drive cable path P2. Specifically, the movable member 1850 receives a first force from the first cable pair 1420 and a second force from the second cable pair 1430, and moves relative to the frame 1810 in response to an imbalance between the first and second forces. As shown, the movable member includes a first fork 1851, a second fork 1852, a first input portion 1861, a second input portion 1863, and a coupler 1870. The first fork 1851 includes two opposing bearing surfaces (only bearing surface 1855 is identified) and a bottom sliding surface 1858. The movable member 1850 is coupled to the frame 1810 such that a bearing 1845 is located within an opening between the opposing bearing surfaces 1855. The movable member 1850 has sufficient clearance to move in a direction orthogonal to the sliding motion direction, such as... Figure 16 As indicated by arrow DD in the diagram. In this manner, during operation of the adjusting mechanism 1800, either of the opposing bearing surfaces 1855 can contact the bearing 1845. The bottom sliding surface 1858 slides in contact with the corresponding sliding surface 1825 of the frame, which limits the downward vertical movement of the movable member 1850 relative to the frame 1810. The second fork 1852 includes two opposing bearing surfaces (only bearing surface 1865 is identified) and a bottom sliding surface 1868. The movable member 1850 is coupled to the frame 1810 such that the bearing 1845 is located within the opening between the opposing bearing surfaces 1865. The movable member 1850 has sufficient clearance to move in a direction orthogonal to the sliding motion direction, such as... Figure 16 As indicated by arrow DD. In this manner, during operation of the adjusting mechanism 1800, either of the opposing bearing surfaces 1865 can contact the bearing 1845. The bottom sliding surface 1868 slides in contact with the corresponding sliding surface 1829 of the frame, which restricts the downward vertical movement of the movable member 1850 relative to the frame 1810.

[0085] A first input portion 1861 defines a first slot in which a first pulley 1871 is coupled and a second slot in which a second pulley 1872 is coupled. A second input portion 1863 defines a third slot in which a third pulley 1873 is coupled and a fourth slot in which a fourth pulley 1874 is coupled. Pulleys 1871, 1872, 1873, and 1874 are coupled within the slots via a coupler 1870, which includes a pin about which the pulley rotates. Furthermore, as... Figure 14 As shown, the coupler 1870 includes a first guide pin 1875 and a second guide pin 1876. See also Figure 16Cable 1420A of the first cable pair 1420 is routed from the first idler pulley 1841 and partially wound around the first pulley 1871. The first guide pin 1875 holds cable 1420A within the cable groove of the first pulley 1871. After exiting the movable member 1850, cable 1420A is routed to the first winch assembly 1710 (see [link]). Figure 15 Similarly, cable 1430A of the second cable pair 1430 is routed from the third idler pulley 1843 and partially wound around the third pulley 1873. The second guide pin 1876 holds cable 1430A within the cable groove of the third pulley 1873. After exiting the movable member 1850, cable 1430A is routed to the second winch assembly 1720 (see...). Figure 15 ).

[0086] Reference Figure 16 Cable 1420B of the first cable pair 1420 is routed from the second idler pulley 1842 and partially wound around the second pulley 1872. A first guide pin 1875 holds cable 1420B within the cable groove of the second pulley 1872. After exiting the movable member 1850, cable 1420B is routed to the first winch assembly 1710 (see [link]). Figure 15 Similarly, cable 1430B of the second cable pair 1430 is routed from the fourth idler pulley 1844 and partially wound around the fourth pulley 1874. The second guide pin 1876 holds cable 1430B within the cable groove of the fourth pulley 1874. After exiting the movable member 1850, cable 1430B is routed to the second winch assembly 1720 (see...). Figure 15 ).

[0087] With this arrangement, the movable member 1850 (and the pulley therein) defines a portion of the first drive cable path P1 and the second drive cable path P2. Therefore, movement of the movable member 1850 relative to the frame 1810 can adjust the lengths of the first drive cable path P1 and the second drive cable path P2. For example, when the device is in the first configuration, the first cable pair 1420 has a first tension T1 and the second cable pair has a second tension T2. ​​In some embodiments, the wrist cable paths of the first cable pair 1420 and the second cable pair 1430 have equal lengths, so tension T1 equals tension T2. ​​In this case, the movable member is centered between the first pin 1824 and the second pin 1828.

[0088] However, when the wrist assembly 1500 is actuated, the wrist cable paths may have unequal lengths, and the tension in the cable alignment may become unbalanced. For example, Figure 18This illustrates a state where the length of the wrist cable path in the first cable pair 1420 is greater than the length of the wrist cable path in the second cable pair 1430. As described herein, this increases the tension in the first cable pair 1420. Therefore, when the device is in the second configuration, as... Figure 18 As shown, the first cable pair 1420 has a first tension T1' that is greater than the second tension T2' of the second cable pair 1430. The increased tension T1' of the first cable pair 1420 acts on the first pulley 1871 (from cable 1420A) and the third pulley 1873 (from cable 1420B). Because the tension T1' is greater than the tension T2' acting on the third pulley 1873 (from cable 1430A) and the fourth pulley 1874 (from cable 1430B), the movable member such as Figure 18 The movement is indicated by arrow CC. This movement alters the drive cable path P1' of the first cable pair 1420 and the drive cable path P2' of the second cable pair 1430. Specifically, the length of drive cable path P1' decreases and the length of drive cable path P2' increases. The simultaneous decrease in drive cable path P1' and increase in drive cable path P2' will cease when the tension in the first cable pair 1420 becomes equal to the tension in the second cable pair 1430. When the device is in the third configuration, as... Figure 19 As shown, the first cable pair 1420 has a first tension T1", which is less than the second tension T2 of the second cable pair 1430. The reduced first tension T1" of the first cable pair 1420 acts on the first pulley 1871 (from cable 1420A) and the third pulley 1873 (from cable 1420B). Because the tension T1" is less than the tension T2" acting on the third pulley 1873 (from cable 1430A) and the fourth pulley 1874 (from cable 1430B), the movable member such as Figure 19 The movement is indicated by arrow EE. This movement alters the drive cable path P1” of the first cable pair 1420 and the drive cable path P2” of the second cable pair 1430. Specifically, the length of drive cable path P1” increases and the length of drive cable path P2” decreases. The simultaneous increase in drive cable path P1” and decrease in drive cable path P2” ceases when the tension in the first cable pair 1420 becomes equal to the tension in the second cable pair 1430. Therefore, the movement of the movable member 1850 is caused by the change in tension in the cable pairs, which is due to the altered cable paths within the device.

[0089] Although various embodiments have been described above, it should be understood that they are presented by way of example only and not by way of limitation. Where the methods and / or diagrams described above indicate specific events and / or process patterns occurring in a specific order, the order of specific events and / or operations may be modified. While these embodiments have been specifically shown and described, it should be understood that various changes in form and detail may be made.

[0090] Although the drive unit 1700 is shown and described as including a winch assembly for actuating cables, in other embodiments, any suitable actuator can be used to actuate the cables. Such actuators may include, for example, linear actuators, actuators including universal joint mounting components, etc. For example, in some embodiments, a linear actuator can move each end of the cable pair by pulling (or releasing) each end of the cable pair linearly rather than by winding (or unwinding) the ends of the cable pair around the winch.

[0091] Although the first fork 1851 and the second fork 1852 of the movable member 1850 are shown as symmetrical, in other embodiments, the movable member may include asymmetrical forks.

[0092] Although the adjusting mechanism 1800 is shown as being located between the winch assembly and the exit path of the shaft 1410, in other embodiments, the adjusting mechanism may be located behind the winch assembly (i.e., the winch assembly may be located between the adjusting mechanism and the exit path of the shaft 1410).

[0093] refer to Figure 4A , Figure 4B , Figure 5 and Figure 6 The described path length compensation for the two pairs of cables typically does not require that the changes in cable path length in the instrument drive perfectly match the changes in cable path length in the more distal parts of the medical device. Specifically, by means of... Figure 4A The path lengths of the pivot 440 and cables 222a and 222b vary depending on the angular orientation and movement of the pivot 440 and the angle at which cables 222a and 222b engage the movable pulley 442. Furthermore, the changes in the cable lengths of cables 222a and 222b in the transmission device 410 may differ from the changes in the cable lengths of cables 224a and 224b in the transmission device 410. Figure 5 The purely linear movement of the movable pulleys 542 and 544 in the device 500 can be achieved through... Figure 4A and Figure 4B The slight arcing movement of pulleys 442 and 444 in the device 400 causes a slight variation in the cable length. Figure 6The four-bar linkage provides a response dependent on the lengths of link 640, mounting arm 340, and the degree of separation of spindle wheel 312. Furthermore, in pitch joints or other mechanisms with non-constant cable lengths, variations in the cable lengths of cables 222a, 222b, 224a, and 224b depend on the specific implementation of the mechanism. However, precise matching of the transmission path length variation with the distal path length variation is generally not required to maintain cable tension within a safe operating range.

[0094] The medical devices and drive mechanisms disclosed herein can provide autonomous or independent path length compensation or alteration, thereby enabling the entire medical device to operate as a cable length-constant mechanism. Specifically, drive mechanisms 300 and medical devices 400, 500, and 600 operate autonomously by altering (e.g., shortening or lengthening) the path length of one or more cable pairs without requiring an external control system, such as a system that monitors cable path length or tension and subsequently actively and dynamically operates or drives the path length alteration mechanism within the device drive. Therefore, some of the disclosed medical devices allow for simpler control techniques and avoid the need for additional interface components that might otherwise be required to allow an external control system to actively operate the path length alteration mechanism.

[0095] Although various embodiments have been described as having specific combinations of features and / or components, other embodiments may have any combination of features and / or components from any of the embodiments discussed above. Various aspects have been described in the context of general medical devices and more specifically surgical instruments; however, the various aspects of the invention are not necessarily limited to use in medical devices.

Claims

1. An apparatus comprising: A wrist assembly having a proximal wrist portion and a distal wrist portion, the proximal wrist portion being coupled to a distal portion of a shaft, wherein actuation of the wrist assembly produces movement of the distal wrist portion relative to the proximal wrist portion; An end effector coupled to the distal wrist portion, wherein actuation of the end effector produces movement of the end effector relative to the distal wrist portion; A cable pair having a first end and a second end, the first end being coupled to the end effector; as well as A drive mechanism coupled to the proximal portion of the shaft, the drive mechanism including an actuator configured to move a second end of the cable pair to actuate the end effector, the second end of the cable pair being routed through the drive mechanism and defining a drive cable path, the drive mechanism including an adjustment mechanism configured to change the drive cable path within the drive mechanism, the adjustment mechanism including a movable member configured to automatically move linearly in response to tension in the cable pair so as to change the length of the drive cable path in response to a change in tension corresponding to a change in the length of the wrist cable path, the change in the length of the drive cable path arising from the linear movement of the movable member being configured to automatically compensate for the change in the length of the wrist cable path so as to maintain the tension within a specific range.

2. The apparatus according to claim 1, wherein the adjusting mechanism comprises: A shuttle is mounted to slide along a guide on the chassis of the transmission device; as well as A pair of pulleys, mounted on the shuttle and engaging with the cable, wherein: Sliding the shuttle along the guide in a first direction increases the length of the transmission cable path; and The shuttle is slid along the guide in a second direction to reduce the length of the transmission cable path.

3. The apparatus of claim 1, wherein the cable pair is a first cable pair, the first end of the first cable pair is coupled to a first tool of the end effector, the drive cable path is a first drive cable path, the actuator is a first actuator, and the apparatus further comprises: The wiring passes through the transmission device to a second cable pair of the wrist assembly, the first end of the second cable pair being coupled to a second tool of the end effector. The transmission device includes a second actuator configured to move a second end of the second cable pair to cause the second cable pair to actuate the second tool of the end effector, the second end of the second cable pair being wired through the transmission device and defining a second transmission cable path, and the adjustment mechanism being configured to change the second transmission cable path.

4. The apparatus of claim 3, wherein the adjusting mechanism includes a movable member operably coupled to the first cable pair and the second cable pair, wherein movement of the movable member simultaneously increases the length of the first transmission cable path and decreases the length of the second transmission cable path.

5. The apparatus of claim 4, wherein the first cable applies a first force on a first side of the movable member, and the second cable applies a second force on a second side of the movable member.

6. The apparatus of claim 5, wherein the movable member comprises a first pulley and a second pulley, a portion of the first cable pair is wound around the first pulley and applies a first force to the first pulley, a portion of the second cable pair is wound around the second pulley and applies a second force to the second pulley, and the movable member is configured to move within the transmission device.

7. The apparatus according to any one of claims 5 or 6, wherein the movable member is configured to translate back and forth along a linear path within the transmission device.

8. The apparatus according to claim 7, wherein: The adjustment mechanism includes a bearing; and The movable member includes a bearing surface that contacts the bearing, and the movable member is configured to translate within the transmission device. The translation of the movable member in the first direction increases the length of the first transmission cable path and decreases the length of the second transmission cable path, and the translation of the movable member along the bearing surface in the second direction decreases the length of the first transmission cable path and increases the length of the second transmission cable path.

9. The apparatus according to claim 8, wherein: The adjustment mechanism includes a frame coupled within the transmission device; The bearing is a first roller bearing coupled to the frame around a first pin; and The adjustment mechanism includes a second roller bearing coupled to the frame around a second pin, and the movable member is configured to translate along a linear path defined between the centerline of the first pin and the centerline of the second pin.

10. The apparatus of claim 5, wherein at least one of the first actuator or a portion of the adjustment mechanism moves within the transmission device to change the length of the first transmission cable path.

11. The apparatus according to any one of claims 1-2, wherein the actuator comprises a winch, the second end of the cable pair is wound around the winch, the winch is configured to rotate about an axle to move the second end of the cable pair, and the axle is configured to move within the transmission to change the length of the transmission cable path.

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