Joint structures and related devices and methods

Abstract

Joint structures and related devices and methods. A joint structure includes a first link and a second link coupled to each other by a joint. The first link and the second link are hingedly movable relative to each other about the joint. An actuation element extends through a first guide channel in the first link and a second guide channel in the second link. The first guide channel terminates in an opening, with the actuation element extending from the first link to extend across the joint to the second link. A first edge portion of the opening is at a first position along a longitudinal axis of the first guide channel and a second edge portion of the opening is at a second position along the longitudinal axis of the first guide channel different from the first position. Systems and devices include associated joint structures.

Description

[0001] This application is a divisional application of Chinese patent application 2020800729443 (PCT / US2020 / 056635), whose international application date is October 21, 2020 and whose national phase entry date is April 18, 2022, and whose name is “Joint structure and related devices and methods”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to U.S. Provisional Application No. 62 / 925,805 (filed on October 25, 2019), entitled “Joint Structures and Related Devices and Methods,” the entire contents of which are incorporated herein by reference. Technical Field

[0004] Aspects of the present disclosure relate to instruments having articulatable joint structures, such as wrists, and related devices, systems, and methods. Specifically, aspects of the present disclosure relate to instruments having articulatable joint structures in response to forces transmitted by an actuating element extending through a link coupled together at the joint. Background Art

[0005] Various tools, such as medical (e.g., surgical) or other industrial instruments, typically include an articulated joint structure that imparts one or more degrees of freedom of motion to such instruments. Such a joint structure may include one or more joints, each of which may articulate with one or more degrees of freedom, which may be the same or different.

[0006] The articulation of the joint structure can be controlled by one or more actuating elements, which are coupled to a manipulator system through various components, and the manipulator system receives input from a user (such as a surgeon or other operator) to position the instrument as needed. Such a manipulator system may include a remotely operated (e.g., computer-controlled) manipulator system or a manipulator system configured for manual operation. In some cases, it is desirable that the joint structure exhibits a relatively high stiffness in any given articulation position to facilitate the ability of the instrument to maintain a given position under a reaction force (such as a reaction force generated by the operation of the end effector of the instrument).

[0007] The instrument may include a joint structure coupling the end effector at a distal portion of the shaft, and articulation of the joint structure may allow the end effector to pivot and orient relative to the shaft. One or more actuation elements extend from a transmission mechanism through the instrument shaft to the (one or more) links of the joint structure, such that forces transmitted by the one or more actuation elements impart articulation movement of the (one or more) links relative to each other about the (one or more) joints, thereby allowing remote "steering" of the joint structure.

[0008] Because the joint structure actuation elements typically travel in positions that are off-centerline of the joint structure, articulating (bending) the joint structure results in bending of the actuation element(s). Such repeated bending may result in changes in the path length affecting the actuation element(s) and may affect other properties of the wrist, such as the ability of the articulated joint structure to withstand externally applied loads without deflecting from the intended position.

[0009] In addition, some joint structures include load-bearing features that may potentially be compromised by the intrusion of environmental matter and debris present in and / or near the working part of the instrument. Such intrusion may be prevented by the use of a protective covering such as a sheath. However, including such a protective covering may result in a relatively larger outer diameter of the instrument compared to an instrument not so equipped. In the case of a desired minimum overall diameter of the instrument, a sheath may be undesirable.

[0010] There is a need to provide an instrument joint structure with improved positioning accuracy and consistency. There is also a need to provide an instrument joint structure with sufficient stiffness under applied loads. There is also a need to provide an instrument joint structure with low sensitivity to the intrusion of environmental materials or debris. Summary of the invention

[0011] Exemplary embodiments of the present disclosure may solve one or more of the above problems and / or may exhibit one or more of the above desirable features.Other features and / or advantages may become apparent from the following description.

[0012] According to at least one exemplary embodiment, a joint structure includes a first link and a second link, the first link and the second link are coupled to each other through a joint, the first link and the second link can be hinged relative to each other around the joint, and the first link is proximal to the second link. An actuating element extends through a first guide channel in the first link and a second guide channel in the second link. The actuating element causes the first link and the second link to hinge relative to each other around the joint in response to a tension applied to the actuating element in a proximal direction. The first guide channel terminates in an opening, wherein the actuating element extends from the first link to extend across the joint to the second link, a first edge portion of the opening is at a first position along the longitudinal axis of the first guide channel, and a second edge portion of the opening is at a second position different from the first position along the longitudinal axis of the first guide channel.

[0013] According to at least another exemplary embodiment, a medical device includes a first link and a second link, which are arranged in series in a proximal-to-distal direction and define an articulated member. An actuating element extends through a first guide channel of the first link and through a second guide channel of the second link in the proximal-to-distal direction. In the non-articulated motion state of the articulated member, a portion of the actuating element between the first guide channel of the first link and the second guide channel of the second link is positioned at a first radial distance from a longitudinal centerline of the articulated member. In the articulated motion state of the articulated member and on the convex side of the articulated shape of the articulated member, a portion of the actuating element between the first guide channel of the first link and the second guide channel of the second link is positioned at a second radial distance from the longitudinal centerline of the articulated member. The second radial distance is greater than the first radial distance.

[0014] According to another exemplary embodiment, a joint structure includes a first link and a second link, wherein the first link and the second link are coupled to each other through a joint. The first link and the second link can be articulated relative to each other around the joint, and the first link is proximal to the second link. An actuating element extends through a first guide channel in the first link and a second guide channel in the second link. The actuating element causes the first link and the second link to articulate relative to each other around the joint in response to a tension applied to the actuating element in a proximal direction. When the joint structure is in an articulated state, when the actuating element is on the concave side of the articulated joint structure, the actuating element is located at a first radial distance from the center line of the joint. When the actuating element is on the convex side of the articulated joint structure, the actuating element is located at a second radial distance from the center line of the joint, and the second radial distance is different from the first radial distance.

[0015] According to yet another exemplary embodiment, a joint structure includes a first link and a second link, the first link and the second link are coupled to each other through a joint, and the first link and the second link can be hinged relative to each other around the joint. The first link is proximal to the second link. An actuating element extends through a first guide channel in the first link and a second guide channel in the second link, and the actuating element causes the first link and the second link to hinge relative to each other around the joint in response to a tension applied to the actuating element in a proximal direction. The first guide channel terminates in an opening, wherein the actuating element extends from the first link to extend across the joint to the second link, and the opening is located in a plane having a non-perpendicular angle to the longitudinal axis of the first guide channel.

[0016] According to yet another exemplary embodiment, a medical device includes a shaft, an end effector, and a wrist that couples the end effector to a distal portion of the shaft. The wrist includes a first link and a second link that are coupled to each other via a joint. The first link and the second link are articulated relative to each other around the joint, and the first link is proximal to the second link. An actuating element extends through a first guide channel in the first link and a second guide channel in the second link. The actuating element causes the first link and the second link to articulate relative to each other around the joint in response to a tension applied to the actuating element in a proximal direction. The first guide channel terminates in an opening, wherein the actuating element extends from the first link to extend across the joint to the second link. A first edge portion of the opening is at a first position along the longitudinal axis of the first guide channel, and a second edge portion of the opening is at a second position different from the first position along the longitudinal axis of the first guide channel.

[0017] According to another exemplary embodiment, a medical device includes a shaft, an end effector, and a wrist, wherein the wrist couples the end effector to a distal portion of the shaft. The wrist includes a first link and a second link, wherein the first link and the second link are coupled to each other via a joint. The first link and the second link can be articulated relative to each other around the joint, and the first link is proximal to the second link. An actuating element extends through a first guide channel in the first link and a second guide channel in the second link. The actuating element causes the first link and the second link to articulate relative to each other around the joint in response to a tension applied to the actuating element in a proximal direction. The first guide channel terminates in an opening, wherein the actuating element extends from the first link to extend across the joint to the second link, and the opening is located in a plane having a non-perpendicular angle to the longitudinal axis of the first guide channel.

[0018] Other purposes, features and / or advantages will be explained in part in the following description, and in part will be obvious from the description, or can be learned by the practice of this disclosure and / or claims. At least some of these purposes and advantages can be realized and obtained by the elements and combinations particularly pointed out in the appended claims.

[0019] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the claims; rather, the claims should be entitled to their full scope, including equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] From the following detailed description, it can be seen thatFigure 1 The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The accompanying drawings illustrate one or more exemplary embodiments of the present disclosure and together with the description explain certain principles and operations. In the accompanying drawings,

[0021] Figure 1 is a schematic diagram of an instrument including a joint structure in the form of a wrist according to the present disclosure.

[0022] Figure 2 is a schematic longitudinal cross-sectional view of an instrument joint structure having a symmetrical actuation element path length across the joint structure.

[0023] Figure 3 is a schematic longitudinal cross-sectional view of an instrument joint structure having an asymmetric actuation element path length across the joint structure according to an embodiment of the present disclosure.

[0024] Figure 4 yes Figure 3 A detailed view of section 4-4 shows the Figure 3 An exemplary configuration of an actuating element guide channel of a connecting rod of a joint structure.

[0025] Figure 5A and Figure 5B yes Figure 3 Detailed perspective view of a joint structure of , showing the outer and inner actuation elements extending away from the proximal link and across the joint in an articulated position of the joint structure.

[0026] Figure 6 is a graph showing the variation of the actuating element moment arm with the articulation angle of the joint structure according to the present disclosure.

[0027] Figure 7 is a graph showing the variation of actuation element path length with articulation angle for an exemplary embodiment of a joint structure according to the present invention.

[0028] Figure 8 is a graph showing the change in the moment arm of the actuating element with the articulation angle according to another exemplary embodiment of the joint structure of the present disclosure.

[0029] Fig. 9 is a graph showing the change in actuation element path length as a function of articulation angle for another exemplary embodiment of a joint structure according to the present disclosure.

[0030] Fig.10 is a graph showing the change in the moment arm of the actuating element with the articulation angle according to another exemplary embodiment of the joint structure of the present disclosure.

[0031] Fig.11 is a graph showing the change in actuation element path length as a function of articulation angle for another exemplary embodiment of a joint structure according to the present disclosure.

[0032] Fig.12 is a schematic diagram of another embodiment of a joint structure according to the present disclosure.

[0033] Fig.13 is a perspective view of another embodiment of a joint structure according to the present disclosure.

[0034] Fig.14 yes Fig.13 Side view of the joint structure.

[0035] Fig.15 is a perspective view of a manipulation system according to an exemplary embodiment of the present disclosure.

[0036] Fig.16 is a partial schematic diagram of an embodiment of a manipulator arm of a manipulation system according to the present disclosure, with two instruments in an installed position. DETAILED DESCRIPTION

[0037] The present disclosure contemplates joint structures including, for example, features that can provide desired stiffness and predictable movement during articulation, such as, but not limited to, a wrist. Various embodiments of the present disclosure contemplate changes in the path along which one or more actuating elements extend across a joint structure. For example, various embodiments of the present disclosure use an asymmetric configuration of the paths of actuating elements positioned crosswise to each other on diameters along an instrument joint structure. Such a configuration can allow controlled and relatively wide-ranging articulation of the joint structure while also maintaining relatively high stiffness to allow precise positioning of the joint structure during bending and return to a neutral (straight) configuration after bending. In addition, such a configuration can provide sufficient stiffness for a joint structure in a bent position to avoid buckling under a compressive force acting along the longitudinal axis of the joint structure.

[0038] In various disclosed embodiments, an asymmetric actuating element path across a joint is achieved by configuring a guide channel in a connecting rod of a joint, the guide channel receiving an actuating element and causing the actuating element to travel across a joint between adjacent connecting rods. For example, a channel may have a channel support portion that terminates at different positions relative to a centerline of a longitudinal axis defined by a connecting rod of a joint. For example, the terminal position of the actuating element channel support portion may depend on a radial distance from the longitudinal axis. A first support portion of the actuating element guide channel may terminate at an edge portion at a first longitudinal position, and a second support portion of the channel may terminate at a second edge portion at a longitudinal position different from the first longitudinal position. In other words, the terminal positions of the support portions of the actuating element guide channel are asymmetric relative to the centerline of the channel. The first portion may be an inner circumferential portion of the channel, and the second portion may be an outer circumferential portion of the channel, wherein the inner circumferential portion and the outer circumferential portion are relative to a radial distance from the longitudinal centerline of the joint. Such an arrangement may provide support for the actuating element at different regions of the actuating element, depending on whether the actuating element is placed along an outer portion or an inner portion of a bend in a bent position of the joint. For example, the outer portion corresponds to a longer path of the actuation element across the joint along the convex portion of the bend, and the inner portion corresponds to a shorter path of the actuation element across the joint along the concave portion of the bend.

[0039] This arrangement of the asymmetric end positions of the actuator guide channel can change the geometric relationship between the actuator element and the connecting rod of the joint structure. The different support areas of the actuator guide channel define the distance from the actuator element to the longitudinal centerline of the joint structure, that is, the moment arm that the actuator element acts on the connecting rod of the joint structure when the joint structure is articulated. The configuration of the support area of ​​the actuator guide channel can be selected to customize the moment arm to provide sufficient leverage on the connecting rod of the joint structure for the tensioned actuator element, thereby providing the desired stiffness level.

[0040] The longitudinal position where the actuating element guide channel support area terminates can be different and can be selected based on various desired results. In order to provide different longitudinal positions where the actuating element guide channel terminates, the opening of the guide channel can be provided in an inclined plane relative to the longitudinal centerline of the guide channel. In an embodiment of a joint structure including a connecting rod with a complementary contact surface (such as a rolling contact surface), the actuating element guide channel can have a support area that is not coplanar with the rolling axis of the rolling contact surface. In some exemplary embodiments, the inclined opening and therefore the longitudinal position of the support area of ​​the actuating element when the actuating element leaves the channel and crosses the joint can be selected to provide a larger moment arm, and the actuating element uses this moment arm to act on the connecting rod of the joint structure. In some exemplary embodiments, the longitudinal position can be selected so that the free path length of the actuating element is customized to compensate for the slack that will otherwise develop in one or two of the actuating elements when the joint structure is articulated. Such an arrangement can also promote the stiffness of the joint structure by eliminating the undesirable slack in one or two actuating elements.

[0041] The present invention also contemplates joint structures that include features that minimize or prevent environmental matter (e.g., tissue or other matter at a surgical site) from interfering with mechanical components. For example, in some exemplary embodiments, the disclosed actuating element guide channel outlets position the actuating elements so that they are outside other interface connection components of the joint structure, for example, contacting bearing surfaces of adjacent connecting rods of the joint structure and / or intermeshing teeth or other gear components. The outside positioning of the actuating elements can facilitate minimizing or preventing environmental matter from interfering with mechanical components.

[0042] In some exemplary embodiments, the joint structure of the present invention includes a rolling contact surface having a cut-out portion near the outer surface of the connecting rod of the joint structure. The cut-out portion provides a gap between portions of the rolling contact surface, and the gap can be sized to prevent material at the working site around the instrument (e.g., tissue at the surgical site) from being clamped between the rolling contact surfaces. Such a feature can be used in combination with an actuator guide channel having different support areas, resulting in an asymmetric end position as described above. Optionally, such a cut-out portion can be used in combination with a joint structure including other actuators and guide channel arrangements.

[0043] Reference now Figure 1, a schematic side view of an embodiment of an instrument 100 (e.g., a surgical instrument) is shown. Although aspects of the present disclosure are discussed in the context of a surgical instrument having a joint structure in the form of a wrist that supports an end effector of the instrument, embodiments of the present disclosure may be used with a variety of instruments used in medical procedures. For example, such instruments include those used for diagnosis, treatment, and sensing, including, for example, imaging instruments, such as endoscopes and other imaging instruments. Thus, medical instruments as used herein encompass a variety of instruments used in surgical, diagnostic, and therapeutic applications. In addition, aspects of the present disclosure may have non-surgical applications such as in other remotely actuatable instruments for inspection and other industrial uses, general robotic uses, manipulation of non-tissue workpieces, and the like.

[0044] The instrument 100 includes a shaft 104 having a transmission mechanism 102 at a proximal end portion of the shaft 104 and an end effector 106 at a distal end portion 107 of the shaft. In an exemplary embodiment, the transmission mechanism 102 is configured to be coupled to a manipulation system (such as the following respectively) Fig.15 and Fig.16 Alternatively, the transport mechanism 102 may be configured for manual operation, such as for use with a manual laparoscopic instrument that may have a handle or other arrangement configured to be directly manipulated by a user.

[0045] The end effector 106 is coupled at the distal portion 107 of the shaft 104 by a joint structure 105, and the joint structure 105 may include one or more articulatable joints to give the end effector 106 one or more degrees of freedom of movement relative to the shaft 104 (for example, to move the end effector 106 in one or more of pitch and yaw). Therefore, the joint structure 105 may include two links coupled together by a joint, or a series of more than two links coupled by a series of joints. For ease and simplicity, the embodiments discussed below show two links and a single joint (referred to as a joint structure below), but the principles disclosed herein can be applied to joint structures having more than two links and more than one joint, as will be familiar to those of ordinary skill in the art. In addition, the joint structure according to an exemplary embodiment may include a series of links connected to the joint, wherein one or more joints have the same or different axes about which they cause the joined links to articulate.

[0046] Certain coordinated movements of the multiple joints may, for example, achieve pivoting of the end effector 106, longitudinal translation, combined movement in pitch and yaw, or other compound movement of the end effector 106 in multiple degrees of freedom relative to the instrument axis 104. Figure 1A single actuation element 108 is shown, but other additional actuation elements may also be operably coupled between the transmission mechanism 102 and the joint structure 105 to actuate articulated motion D of the joint structure 105 along various degrees of freedom associated with various joints of the joint structure 105, such as various wrists.

[0047] The end effector 106 may be operated manually or by a manipulation system (e.g., Fig.15 and 16 The transmission mechanism 102 is controlled by a driver of the manipulation system (shown in FIG. 1 ). The transmission mechanism 102 includes various mechanical and / or electromechanical devices that transmit movement, energy, and / or signals, such as from the manipulation system or from an input end at the transmission mechanism 102 that can be operated by a user, to the end effector 106. For example, one or more actuator elements ( Figure 1 An actuating element 108 is shown extending from the transmission mechanism 102 through the shaft 104 and to the end effector 106 to operably couple the transmission mechanism 102 (or a component thereof) to the end effector 106. A force applied by the transmission mechanism 102 to the actuating element 108 can actuate (e.g., close, open, or otherwise control) the end effector 106. Figure 1 The end effector 106 shown includes a pair of opposing jaw members, but other end effector configurations (such as staplers, clip appliers, ligation tools, and other tools) are considered within the scope of the present disclosure. In various embodiments, the actuation element can include a flexible member, such as a polymer or metal (e.g., tungsten) solid or braided actuation element.

[0048] Reference now Figure 2 , shows a side view of a joint structure 210 according to the prior art. The joint structure 210 joins a first link 212 and a second link 214 at opposing rounded contact surfaces 216, which define a rolling axis A R1 , A R2 When the joint structure 210 is articulated, each of the first link 212 and the second link 214 rotates around the rolling axis A R1 , A R2Rotation. The joint structure 210 includes intermeshing parts 218 and 220, and when the joint structure 210 articulates, the intermeshing parts 218 and 220 prevent sliding between the first link 212 and the second link 214. Although exemplary embodiments of the present disclosure are shown and described herein with reference to joint structures having rounded contact surfaces (such as 216), aspects of the present disclosure are equally applicable to joint structures and other joint structures having other kinematic control components (such as pin joints and other configurations of articulated and / or flexible joints). In addition, although the description and drawings herein show joint structures having a single degree of freedom, aspects of the present disclosure are also applicable to joint structures having multiple joints and therefore multiple degrees of freedom (such as parallel motion mechanisms or other serial joints).

[0049] One or more actuating elements extend through the joint structure 210. Figure 1 As discussed, one or more actuating elements may be operably coupled to the transmission mechanism 102 ( Figure 1 ) to actuate the articulation movement of the joint structure 210. Figure 2 In the exemplary embodiment of FIG. 2 , two actuating elements 222 and 224 are visible. In order to actuate the joint structure 210 from a neutral position (not shown) to Figure 2 The actuating element 222 is tensioned and the actuating element 224 is relaxed by articulating the actuating element 222 to the position shown. The tensioning and relaxing can be achieved by coupling the actuating elements 222 and 224 to the transmission mechanism 102 ( Figure 1 ) in a single capstan such that when the capstan rotates, one actuating element is released and another actuating element is put in at the same time. In some configurations, actuating elements 222 and 224 can represent two parts of a single actuating element having a middle portion wound around the capstan. Therefore, as used herein, actuating elements 222 and 224 can represent individual actuating elements or separate parts of a single actuating element. Figure 2 The arrangement of actuating elements 222 and 224 in may be referred to as a "pull-pull arrangement". The simultaneous tensioning and relaxation of the opposing actuating elements creates a coupling that causes the joint to rotate (i.e., articulate) about an articulation axis. Although the exemplary embodiments discussed herein are characterized by a "pull-pull" arrangement, the present disclosure encompasses other arrangements of actuating elements, such as a push-pull or other configurations.

[0050] like Figure 2 As shown, the actuating elements 222 and 224 extend through corresponding actuating element guide channels 225, 226 in the first link 212 and through actuating element guide channels 227, 228 in the second link 214. Figure 2 In the joint structure configuration, the actuating element guide channels 225, 226 in the first link 212 terminate in a plane L1 which is parallel to the rolling axis A.R1 The actuating element guide channels 227, 228 of the second link 214 terminate in a plane L2 that passes through the rolling axis A. R2 and is orthogonal to the longitudinal axis of the actuating element guide channels 227 and 228. Geometrically, this configuration promotes conservation of the path lengths of the actuating elements 222 and 224 as the joint structure 210 articulates from the neutral position (i.e., the sum of the path lengths of the actuating element guide channels remains constant). In other words, as the joint structure 210 articulates from the neutral position, a decrease in the distance between the actuating element guide channels 226 and 228 on the inside of the joint structure 210 is offset by an equal increase in the distance between the actuating element guide channels 225 and 227 on the outside of the joint structure 210. This configuration is useful for actuating elements 222 and 224 that represent separate cables or are arranged around a transmission mechanism (e.g., Figure 2 A joint architecture in which different portions of a single cable or other member are wound around a capstan in the transmission mechanism 102 in the joint structure 210 may be desirable. For example, when a portion of the actuating element 222 is paid out from the capstan, an equal portion of the actuating element 224 is wound onto the capstan, thereby preventing significant slack from developing on either side of the joint structure 210.

[0051] When the joint structure 210 is in the neutral position, the actuating elements 222 and 224 act on the segments to articulate the joint structure 210 with a moment arm equal to the moment arm from the axis A. R1 and A R2 Plane A L The distance from the center line of the corresponding actuating element guide channel 226, 228. Figure 2 , the joint structure 210 is shown articulating from a neutral position. As the joint structure 210 articulates from the neutral position, the moment arms of the actuating elements 222 and 224 acting on the segments to articulate the joint structure 210 effectively change based on the degree of articulation of the joint structure 210. For example, when the joint structure 210 articulates to an angle of 45 degrees between the first segment 212 and the second segment 214, the length of the moment arm effectively decreases because the unsupported length of the actuating elements 222 and 224 between the actuating element guide channels 225, 226, 227, 228 is pulled closer to the axis passing through A. R1 and A R2 Plane A L That is, considering the actuating element 222 and the first segment 212, when the segments articulate relative to each other, the moment arm becomes equal to the distance H1, which is the distance from line A to line B. L The distance to the actuator 222 can be obtained by multiplying the distance through the axis A R1and A R2 Plane A L and the longitudinal center line L of the first segment 212 C1 The distance H1 is calculated by taking the cosine of the angle between Figure 2 It is obvious that the distance H1 is less than the distance from the axis A R1 The length of the center line of the guide channel 225 located in the plane L1 is reduced, and therefore when the first link 212 and the second link 214 are hinged relative to each other, the actuating element 222 acts on the first link 212 with a shorter moment arm. The moment arm of each of the actuating elements 222, 224 acting on the first link 212 and the second link 214 is similarly reduced.

[0052] Because the positions of the first and second links 212, 214 relative to each other are at least partially controlled and maintained by the actuating elements 222, 224, when the first and second links 212, 214 are subjected to external forces (such as applied to the instrument (e.g., Figure 1 The reduction in the moment arm of the actuating elements 222, 224 acting on the first and second links 212, 214 correspondingly increases the force applied to the actuating elements 222, 224 when the reaction force of the instrument 100 in the joint structure 210 is increased. Therefore, as the angle of articulation of the joint structure 210 increases, the "stiffness" of the joint structure 210 (i.e., the ability of the joint structure 210 to withstand the applied external force without deflecting from the intended position under the applied external force) decreases.

[0053] The present disclosure contemplates an actuating element guide channel having a configuration that changes the effective moment arm as the angle between the joint structure links changes. An actuating element guide channel having such a configuration can provide conservation of length of the actuating element, or in some embodiments, provide an approximate conservation of length that is sufficiently close to true conservation of length so as to avoid any excessive slack or over-tension as the joint structure articulates through its angular travel.

[0054] Reference now Figure 3 , shows a joint structure 430 according to the present invention, and the joint structure 430 has the same Figure 2 The joint structure 430 includes a first link 432 and a second link 434, which are articulated relative to each other via a joint including a rolling contact surface 416, which defines an articulation axis A. R1 and A R2 . Combined with Figure 2Like the joint structure 210 shown and described above, the joint structure 430 includes intermeshing components 418 and 420 that prevent sliding between the first link 432 and the second link 434 when the joint structure 430 articulates. Such intermeshing components are optional, and some exemplary embodiments of the present disclosure do not include such intermeshing components.

[0055] Each of the first link 432 and the second link 434 includes an actuating element guide channel 435, 436 and 437, 438. The actuating elements 422 and 424 pass through the corresponding actuating element guide channels 435, 436 and 437, 438, and coordinate the tensioning and releasing of the actuating elements 422 and 424 (e.g., by Figure 1 The actuating element guide channels 435, 436 and 437, 438 include features for changing the effective moment arms of the actuating elements 422 and 424 acting on the first link 432 and the second link 434 according to the angle of the hinged motion between the first link 432 and the second link 434.

[0056] For example, Figure 3 As shown, each actuating element guide channel 435, 436 and 437, 438 ends at an edge portion offset relative to the planes L1 and L2. In other words, the edge portions of the actuating element guide channels 435, 436 and 437, 438 are not located in the planes L1 and L2, but the edge portions are configured so that the actuating elements 422 and 424 leave the channels 435, 436 and 437, 438 at different longitudinal positions of the actuating elements 422 and 424, depending on the distance from the hinge axis A. R1 and A R2 Plane A L In other words, the line of the support portion where the channel (e.g., channel 435) terminates forms an oblique angle relative to the longitudinal axis of the channel. In this way, the configuration of the actuating element guide channels 435, 436 and 437, 438 can be used to change the moment arm of the actuating elements 422 and 424 acting on the first link 432 and the second link 434 according to the angle of the articulation movement of the joint structure 430, as further discussed below. For simplicity of description, the actuating element guide channels 435 and 437 are specifically discussed below, but all actuating element guide channels 435, 436 and 437, 438 may include corresponding features.

[0057] like Figure 3As shown, the actuator guide channel 435 has an inner portion 440 that extends parallel to the length of the actuator guide channel 435 (i.e., in a direction toward the second link 434) beyond the plane L1 by a distance D1. The actuator guide channel 435 has an outer portion 442 that terminates a distance D2 before the plane L1 (i.e., in a direction away from the second link 434). Figure 3 In the exemplary embodiment of , each of the four actuation element guide channels 435 , 436 , 437 , 438 has a similar configuration with an inner portion 440 and an outer portion 442 .

[0058] exist Figure 3 , the joint structure 430 is shown as articulating at an angle of approximately 60 degrees between a first link 432 and a second link 434. For the purposes of this specification, the "inside" of the articulating joint structure 430 is the portion of the joint structure 430 that is on the inside of the bend angle (i.e., on the inside of the bend angle). Figure 3 ), and the "outside" of the articulated joint structure 430 is the portion of the joint structure 430 that is on the outside of the bend angle (i.e., on the outside of the Figure 3 In other words, "outer" or "outside" refers to the convex portion of the bend of the joint, and "inner" or "inboard" refers to the concave portion of the bend of the joint.

[0059] like Figure 3 As shown, when the joint structure 430 is articulated, the outer actuating element 422 contacts the inner portion 440 of the actuating element guide channels 435 and 437. Because the inner portion 440 of the actuating element guide channels 435 and 437 does not end in the planes L1 and L2, the outer actuating element 422 contacts the inner portion 440 of the actuating element guide channels 435 and 437. Figure 2 Compared to the design discussed above, the actuating element 422 is positioned from the axis of rotation A through R1 and A R2 That is, in Figure 3 In the embodiment of the present invention, when the joint structure 430 is articulated from the neutral position, when passing through the axis A R1 The line between the actuator support portion 440 and the rotation axis A is perpendicular to the rotation axis A. R1 and A R2 Plane A L , the moment arm of the actuating element 422 acting on the connecting rods 432 and 434 initially increases and reaches a maximum value H1.

[0060] like Figure 3As shown in FIG. 1 , when the joint structure 430 articulates, the actuating element 424 on the inner side of the joint structure 430 breaks at the outer portion 442 of the actuating element guide channels 436 and 438. Because the outer portion 442 does not end in the planes L1 and L2, but ends at a distance D2 before the plane L1 (i.e., on the side of the plane L1 opposite to the contact surface 416), the outer portion 442 is not connected to the outer portion 442 of the joint structure 430. Figure 2 Compared to the embodiment discussed, the actuating element 424 is positioned to pass through A R1 and A R2 That is, when the joint structure 430 is articulated, the moment arm H2 of the actuating element 424 acting on the connecting rods 432 and 434 is greater than Figure 3 The corresponding moment arm in the embodiment of .

[0061] The distances D1 and D2 may be selected based on the desired characteristics of the joint structure 430 and therefore the effective moment arm of the actuating element acting on the joint structure link when the joint structure articulates. Figure 3 In some embodiments, distances D1 and D2 are equal, which configuration provides conservation of the length of the combined path of actuating elements 422 and 424 throughout the range of motion of joint structure 430. With this configuration, moment arms H1 and H2 are also equal because they vary throughout the range of articulation motion of joint structure 430. In some embodiments, distances D1 and D2 are selected to be unequal. While this arrangement may affect conservation of length of the actuating elements, D1 and D2 can be selected to "tune" joint structure 430 with desired characteristics, as described below in conjunction with Figure 6-10 The example embodiments discussed above.

[0062] An example of an arrangement that may require different distances D1 and D2 is a configuration in which the joint structure 430 has a relatively high inherent stiffness, for example due to the presence of an outer sheath, an internal drive member, or other components that extend along the joint structure and exhibit flexural elasticity. In such a configuration, the elasticity of the sheath, drive member, or other components can cause the tension in the inner actuating element (i.e., the control actuating element on the "inside" of the joint structure when the joint structure articulates) to be greater than the outer actuating element, causing the inner actuating element to stretch and the outer actuating element to relax. The development of relaxation leads to a loss of stiffness of the joint structure because external reaction forces or internal forces (such as tension or compression in the drive member) act on the joint structure.

[0063] According to embodiments of the present disclosure, the joint structure can be configured with unequal distances D1 and D2 to compensate for such slack development. For example, in a configuration where D1 is greater than D2, the actuating element path length is not conserved, but becomes longer as the angle of the joint structure articulation increases. In this way, slack that would otherwise be generated in the outer actuating element is compensated by the increased path length when the joint structure articulates, thereby promoting increased joint structure stiffness compared to conventional joint structure designs.

[0064] Reference now Figure 4 , shows an enlarged view of the connecting rod 532 of the joint structure according to an embodiment of the present disclosure to more clearly illustrate various aspects of the present disclosure. The actuating element guide channel 535 is along the longitudinal axis A of the connecting rod 532. L The actuator guide channel 535 extends along the longitudinal axis A. L Line T at an angle L In the embodiment of FIG. 5 , the cross-sectional shape of the actuating element guide channel 535 is circular. Therefore, along line T L , the guide channel 535 has a generally elliptical opening. One exemplary embodiment is characterized by a non-circular guide channel cross-sectional shape, such as but not limited to a straight line shape, a polygonal shape, an oval shape, etc. Figure 4 In an exemplary embodiment of the present invention, when the joint structure articulates, the actuating element (e.g., Figure 3 The portion of the actuator guide channel 535 on which the actuator elements 422 and 424 are bent is rounded with a radius r. The radius r is optional and can help reduce (e.g., minimize) friction of the actuator against the actuator guide when the joint structure is articulated, and can also reduce stress in the actuator by increasing the bending radius of the actuator. In an exemplary embodiment of the present disclosure, the radius r can be, for example, in the range of from 0 to 0.1 inches (2.54 mm). Figure 4 In an embodiment of the present invention, the radius r is 0.033 inches (0.838 mm). Other values ​​of r (such as other values ​​between 0 and 0.1 inches, or values ​​greater than 0.1 inches) are within the scope of the present disclosure. Such changes in radius r can also affect the actuating element path length when the wrist articulates. For example, with all other parameters being equal, an increase in radius r on one side of the guide channel can have a similar effect on the path length and moment arm as changing distance D1 or D2. In other exemplary embodiments, the actuating element guide channel does not include radius r.

[0065] Figure 5A and 5B Shown in an articulated position Figure 3 A detailed perspective view of the joint structure. Figure 5A, the outer (ie, convex) side of the articulated joint structure is shown, and the actuating elements 422 and 424 rest on the inner portion 440 of the actuating element guide channel, as shown above in conjunction with Figure 3 discussed. Figure 5B In FIG. 4 , the inner (ie, concave) side of the articulated joint structure is shown, and the actuating elements 422 and 424 rest on the actuating element guide channel outer portion 442. Figure 5A and 5B , the generally oval shape of the actuating element guide channel 435 is apparent. Figure 3 , 4 , 5A and 5B has a substantially circular cross-sectional shape, but the guide channel according to the exemplary embodiment of the present disclosure may have various non-circular cross-sectional shapes as described above.

[0066] Figure 6-11 is a graph showing the operating characteristics of various example configurations of joint structures according to the present disclosure tested by the inventors. Figure 6 , shows a graph of the moment arm of an inner actuating element (i.e., an actuating element located on the interior of the bending operational characteristics of a joint structure) according to an exemplary embodiment of the present disclosure. In the exemplary embodiment, the radius is 0.033 inches (0.838 mm). As described above, in this embodiment, D1 and D2 are selected to be unequal, for example, to absorb any slack that occurs when the joint structure articulates. In the exemplary embodiment, D1 is selected to be 0.025 inches (0.635 mm), and D2 is selected to be 0.031 inches (0.787 mm). As Figure 6 As shown, when the joint structure articulates, the moment arm of the actuating element initially increases slightly from 0.1 inches (0.254 mm), and once the articulation exceeds 50 degrees, it only drops below 0.1 inches. Throughout the entire articulation range from 0 to 60 degrees, Figure 6 The embodiment has a larger moment arm, as indicated by line 652, than the conventional design indicated by dashed line 650.

[0067] Reference now Figure 7 , shows a diagram for Figure 6 FIG. 1 shows a graph of the total path length traveled by the actuating element of the same embodiment as a function of the articulation angle. Figure 7 As shown, the total path length begins to increase as the articulation angle increases beyond about 30 degrees. As described above, such an increase in path length can compensate for the development of slack due to high forces on the inner actuation elements when the joint structure articulates.

[0068] Figure 8is a graph showing the length of the moment arm as a function of the articulation angle of the joint structure for another exemplary embodiment of a joint structure according to the present disclosure. In this embodiment, D1 and D2 are nearly equal, with D1 being 0.036 inches (0.914 mm) and D2 being 0.0361 inches (0.917 mm). As described above, this arrangement provides increased joint structure stiffness due to the increased moment arm throughout the range of articulation of the joint structure. Similar to Figure 6 and Figure 7 Related embodiments, Figure 8 The embodiment includes a rounded actuating element outlet having a radius of 0.033 inches (0.838 mm). Figure 8 As shown, the inner actuator element moment arm remains equal to or greater than 0.1 inches (0.254 mm) throughout the entire range of articulation motion of the joint structure from 0 degrees to 60 degrees.

[0069] Reference now Fig. 9 , the total path length variation over the range of articulation from 0 to 60 degrees is only 0.003 inches (0.0762 mm), and this arrangement provides almost perfect conservation of length over 60 degrees of articulation. Such an arrangement may be advantageous in situations where a larger moment arm is desired that exceeds potential slack consumption.

[0070] Fig.10 and 11 is a graph illustrating characteristics associated with another exemplary embodiment of a joint structure according to the present disclosure. In this embodiment, the offset distance of the actuating element guide outlet is selected to provide an increase in path length when the joint structure articulates. For example, Fig.10 and 11 The embodiment represented by the graph of is characterized by a dimension D1 of 0.036 inches (0.9144 mm) and a dimension D2 of 0.0115 inches (0.292 mm). Figure 6-9 In a related embodiment, this embodiment is further characterized by a radius of 0.033 inches (0.838 mm) at the outlet of the actuating element.

[0071] like Fig.10 As shown, the moment arm of the inner actuator element is greater than that of the conventional joint structure within the range of articulation motion (in Fig.10 However, as the amount of articulation exceeds about 20 degrees, the inner actuator moment arm does begin to decrease from its initial value of 0.1 inches (0.254 mm) at the initial 0 degree articulation position. Fig.11, the total path length increases throughout the range of articulation from 0 to 60 degrees, and approaches 0.01 inches (0.254 mm) at 60 degrees of articulation. As described above, such an arrangement can compensate for the development of slack in the outer actuating elements as the joint structure articulates, while still providing an increase in the moment arm over conventional designs.

[0072] In addition to the slack dissipation and joint structural stiffness effects provided by using an asymmetric actuation element path across a joint, changing the actuation element path across a joint according to the various embodiments described above can also reduce the likelihood of mechanical interference between joint structural components and features of the environment in which a device including the joint structure is used. For example, again referring to Figure 2 , in the articulated position, the interengaging components 218 and 220 extend beyond the actuation element 224. In some cases, contact between the interengaging components 218 and 220 and tissue surrounding an operative site, such as where an instrument including a joint structure is used, could potentially result in undesirable interference between the interengaging components and the surrounding tissue.

[0073] like Figure 3 As shown, in the articulated position, since the inner actuating element guide portion 440 extends beyond the axis A R1 and A R2 , the actuation element 424 of the joint structure according to an exemplary embodiment of the present disclosure is positioned outside the interengaging components 418 and 420. In this way, the possibility of tissue or other environmental substances interfering with the interengaging components 418 and 420 is reduced.

[0074] Exemplary embodiments of joint structures according to the present disclosure may include additional features that are configured to avoid interference between components of the joint structure and surrounding environmental matter. For example, in some embodiments, an instrument including a joint structure according to an embodiment of the present disclosure may include a flexible sheath, sleeve, or other external protective component to prevent environmental matter from interfering between components of the joint structure. However, such a sleeve may facilitate an increased overall diameter of the instrument. Therefore, in some exemplary embodiments (particularly embodiments of instruments configured for minimally invasive surgical procedures), the components may include features that are configured to mitigate such interference without the need for any sleeve or other external protective component. For example, now referring to Fig.12 , a perspective view of a joint structure 1252 is shown. The joint structure 1252 includes a joint 1254 between a first link 1255 and a second link 1256. The joint 1254 includes a rolling contact surface 1216 that limits the motion of the joint 1254. Under some conditions, environmental matter (such as tissue) may interfere with the rolling contact surface 1216, such as being sandwiched between opposing contact surfaces 1216.

[0075] Embodiments of the present invention may include features configured to reduce the likelihood of environmental matter interfering between rolling contact surfaces 1216. For example, referring now to Fig.13 and 14 , the joint structure 1358 includes rolling contact surfaces 1360 and 1362, one or both of which may be radially inward relative to the adjacent let-off portion. Fig.13 In the exemplary embodiment of FIG. 1 , rolling contact surface 1362 is adjacent to cutout portion 1364, while rolling contact surface 1360 does not have any adjacent cutout portion. Fig.14 As shown, the cutout portion 1364 forms a gap 1370 between the rolling contact surface 1360 and the cutout portion 1364. The contact area 1368 of the rolling contact surface 1362 contacts the rolling contact surface 1360 to limit the movement of the joint structure components and support the relative rotation between the joint structure components. In other words, the cutout portion 1364 creates a surface portion of the rolling contact surface 1362 that is spaced apart from the opposing rolling contact surface 1360 of the outer surface 1372 of the adjacent joint structure 1358.

[0076] The gap 1370 between rolling contact surfaces 1360 and 1362 prevents environmental matter (such as tissue) from being caught or trapped between the contact area 1368 of rolling contact surface 1360 and rolling contact surface 1362. The gap 1370 can range from about 0.001 inches (0.0254 mm) to about 0.01 inches (0.254 mm) or more. In an exemplary embodiment, the gap 1370 is about 0.007 inches (0.178 mm).

[0077] Gap 1370 extends radially inwardly from outer surface 1372 of joint structure 1358 a distance D r The radial distance D r The size of gap 1370 may be selected to be larger than that of gap 1370 to provide a sufficient "buffer zone" to prevent environmental matter (such as tissue) from interfering with (e.g., being sandwiched by) contact area 1368 and rolling contact surface 1362. Fig.13 and 14 In the embodiment, the radial distance D r Greater than twice the size of gap 1370, i.e., radial distance D r is about 0.014 inches (0.0356 mm) or greater. In other exemplary embodiments, the radial distance D r It may be less than the value of gap 1370, less than twice the value of gap 1370, greater than twice the value of gap 1370, or other values.

[0078] Because gap 1370 causes contact region 1368 to have a smaller surface area than a corresponding rolling contact surface without gap 1370, the stress level present on contact region 1368 and the corresponding area of ​​rolling contact surface 1360 may potentially be greater than in Fig.12 To compensate for the greater stress levels, the joint structural components can be made of materials having a compressive strength sufficient to withstand the greater pressure levels that exist between the components due to gap 1370. In addition, contact area 1368 and rolling contact surface 1360 can be treated to provide greater strength, such as by heat treatment, surface modification (e.g., polishing, plating with various wear resistant materials), or other manufacturing processes.

[0079] exist Fig.13 In an exemplary embodiment of the present invention, rolling contact surface 1362 includes a cutout portion 1364, while rolling contact surface 1360 is not cutout. In other embodiments, the arrangement can be reversed, that is, rolling contact surface 1360 can include a cutout portion 1364, while rolling contact surface 1362 can be not cutout. In other exemplary embodiments, both rolling contact surfaces 1360 and 1362 can include similar cutout portions.

[0080] Exemplary embodiments of the present invention provide joint structures with improved rigidity and / or actuating element slack compensation compared to conventional joints.Such joints may also include features that may mitigate the possibility of environmental substances (such as tissues, for example, during surgical procedures) interfering with the mechanical operation of the joint structure.

[0081] Instruments including embodiments described herein may be used, for example, with a teleoperated computer-assisted surgical system employing robotics, such as a DA Surgical systems (such as DA VINCI Surgical system or DA VINCI Surgical systems, DA VINCI SP and ION (both with or without The present disclosure is not limited to use with surgical instruments for use with such surgical systems. For example, the various embodiments described herein may optionally be used in conjunction with handheld, manual or semi-automatic surgical instruments (such as surgical instruments used in manual laparoscopic surgery) or other surgical and non-surgical instruments.

[0082] As described above, according to various embodiments, the surgical instrument of the present disclosure is configured for use in a remotely operated computer-assisted surgical system (sometimes referred to as a robotic surgical system) that employs robotics. Fig.15 , shows an embodiment of a manipulation system 1500 of a computer-assisted surgical system to which surgical instruments are configured to be mounted for use. Such a surgical system may also include a user control system (such as a surgeon's console (not shown)) for receiving input from a user to control instruments coupled to the manipulation system 1500, and auxiliary systems (such as those described above with DAVINCI AND DA VINCI DA VINCI SP and auxiliary systems associated with the Ion system).

[0083] like Fig.15 As shown in the embodiment of FIG. 1 , the manipulation system 1500 includes a base 1520, a main column 1540, and a main boom 1560 connected to the main column 1540. The manipulation system 1500 also includes a plurality of manipulator arms 1510, 1511, 1512, 1513, each of which is connected to the main boom 1560. The manipulator arms 1510, 1511, 1512, 1513 each include an instrument mounting portion 1522 to which an instrument 1530 can be mounted, and the instrument mounting portion 1522 is shown as being attached to the arm 1510.

[0084] According to an embodiment, the instrument mounting portion 1522 includes a drive assembly 1523 and a sleeve mounting member 1524, wherein a transmission mechanism 1534 of the instrument 1530 (which may generally correspond to a combination of Figure 1 The transmission mechanism 102 discussed above is connected to the drive assembly 1523. The cannula mount 1524 is configured to hold a cannula 1536 through which the shaft 1532 of the instrument 1530 can extend to the surgical site during the surgical procedure. Although for ease of viewing, Fig.15 The embodiment shows the instrument 1530 attached only to the manipulator arm 1510 , but the instrument may be attached to any and each of the manipulator arms 1510 , 1511 , 1512 , 1513 .

[0085] Other configurations of surgical systems are also contemplated (such as surgical systems configured for single-port surgery). For example, referring now to Fig.16 , shows a portion of an embodiment of a manipulator arm 2140 of a manipulator system, wherein two surgical instruments 2300, 2310 are in an installed position. The surgical instruments 2300, 2310 may generally correspond to the instruments discussed above, such as in combination with Figure 1The disclosed device 100. For example, the embodiments described herein may be used with the DA VINCI commercialized by Intuitive Surgical, Inc. of Sunnyvale, California. For simplicity, Fig.16 The schematic illustration of depicts only two surgical instruments, but as is familiar to those skilled in the art, more than two surgical instruments may be mounted in a mounting position at the manipulation system. Each surgical instrument 2300, 2310 includes a shaft 2320, 2330 having a movable end effector or endoscope, camera or other sensing device at the distal end, and may or may not include a wrist mechanism (not shown) to control movement of the distal end.

[0086] exist Fig.16 In the embodiment of the present invention, the distal end portion of the surgical instrument 2300, 2310 is received by a single port structure 2380 for introduction into the patient. As shown, the port structure includes a cannula and an instrument entry guide inserted into the cannula. Individual instruments are inserted into the entry guide to reach the surgical site.

[0087] Other configurations of manipulation systems that may be used in conjunction with the present disclosure may use several individual manipulator arms. Additionally, an individual manipulator arm may include a single instrument or multiple instruments. Furthermore, as described above, the instrument may be a surgical instrument with an end effector, or may be a camera instrument or other sensing instrument used to provide information (e.g., visualization, electrophysiological activity, pressure, fluid flow, and / or other sensing data) of a remote surgical site during a surgical procedure.

[0088] The transmission mechanism 2385, 2390 (which generally corresponds to the combination Figure 1 The disclosed transmission mechanism 102 is disposed at the proximal end of each shaft 2320, 2330 and is connected to the drive assembly 2420, 2430 through the sterile adapter 2400, 2410. The drive assembly 2420, 2430 includes various internal mechanisms (not shown) that are controlled by a controller (e.g., at a control cart of the surgical system) to respond to input commands at the surgeon-side console of the surgical system to transmit force to the transmission mechanism 2385, 2390 to actuate the surgical instruments 2300, 2310.

[0089] The embodiments described herein are not limited to Fig.15 and 16Embodiments of the present invention and various other teleoperated computer-assisted surgical system configurations may be used with the embodiments described herein. The diameter or diameters of the instrument shaft, wrist mechanism, and end effector are typically selected based on the size of the cannula to be used with the instrument and in accordance with the surgical procedure being performed.

[0090] This description and the accompanying drawings of illustrated exemplary embodiments should not be considered as limiting. Without departing from the scope of this specification and the claimed invention (including equivalents), various mechanical, composition, structure, electrical and operational changes can be carried out. In some cases, known structures and technologies are not shown or described in detail to avoid blurring the present disclosure. The same numbers in two or more figures represent the same or similar elements. In addition, the elements described in detail with reference to an embodiment and their related features can be included in other embodiments that are not specifically shown or described in any practicable situation. For example, if an element is described in detail with reference to an embodiment, and the element is not described with reference to the second embodiment, but the element may also be required to be included in the second embodiment.

[0091] For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers expressing quantities, percentages or ratios, as well as other numerical values ​​used in the specification and claims should be understood as being modified in all instances by the term "about", provided that they have not been so modified. Therefore, unless indicated to the contrary, the numerical parameters set forth in the specification and the appended claims are approximate values ​​that may vary depending upon the desired properties sought to be obtained. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques, and not attempting to limit the application of the doctrine of equivalents to the scope of the claims.

[0092] It should be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the," as well as any singular use of any word, include plural referents unless expressly and unambiguously limited to one referent. As used herein, the term "include" and its grammatical variations are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that can be substituted or added to the listed items.

[0093] In addition, the terms of this description are not intended to limit the present invention. For example, spatially relative terms, such as "below", "below", "lower", "above", "upper", "near side", "distal side", etc., can be used to describe the relationship between an element or feature and another element or feature shown in the figure. These spatially relative terms are intended to cover the different positions (positions) (that is, positions (locations)) and orientations (that is, rotational placement) of the equipment in use or operation other than the positions and orientations shown in the figures. For example, if the equipment in the figure is flipped, the elements described as "below" or "below" other elements or features will be "above" or "on" other elements or features. Therefore, the exemplary term "below" can cover both the position and direction of the upper and lower parts. The equipment can be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used in this article are interpreted accordingly.

[0094] In view of the disclosure herein, further modifications and alternative embodiments will be apparent to those of ordinary skill in the art. For example, systems and methods may include additional components or steps that are omitted from the figures and descriptions for clarity of operation. Therefore, this specification is to be interpreted as illustrative only and is intended to teach those skilled in the art the general manner of implementing the content of this teaching. It should be understood that the various embodiments shown and described herein will be considered exemplary. Elements and materials and the arrangement of these elements and materials may replace those shown and described herein, parts and processes may be reversed, and certain features of this teaching may be used independently, which will all be apparent to those skilled in the art after benefiting from the description herein. Changes may be made to the elements described herein without departing from the spirit and scope of this teaching and the following claims.

[0095] It is to be understood that the specific examples and embodiments set forth herein are non-limiting and that modifications in structure, dimensions, materials, and methods may be made without departing from the scope of the present teachings.

[0096] Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. The specification and examples are intended to be considered exemplary only, and the appended claims are to be given their fullest scope, including equivalents, under applicable law.

Claims

1. A joint structure, comprising: A first link and a second link, the first link and the second link are coupled to each other through a joint, the first link and the second link are hinge-movable relative to each other around the joint, and the first link is proximal to the second link; as well as an actuation element extending through a first guide channel in the first link and a second guide channel in the second link, wherein the actuation element causes articulated movement of the first link and the second link relative to each other about the joint in response to tension applied to the actuation element in a proximal direction; in: The first guide channel terminates in an opening, wherein the actuating element extends from the first link to extend across the joint to the second link, a first edge portion of the opening is at a first position along the longitudinal axis of the first guide channel, and a second edge portion of the opening is at a second position along the longitudinal axis of the first guide channel that is different from the first position.

2. The joint structure according to claim 1, wherein the second guide channel terminates in a second opening, wherein the actuating element extends from the second link to extend across the joint to the first link, a first edge portion of the second opening is at a first position along the longitudinal axis of the second guide channel, and a second edge portion of the opening is at a second position along the longitudinal axis of the second guide channel that is different from the first position.

3. The joint structure of claim 1, wherein the first position along the longitudinal axis is on a first side of a plane that intersects the first link's rotational axis about the joint, and the second position along the longitudinal axis is on a second side opposite to the first side of the plane.

4. The joint structure of claim 3, wherein the first position along the longitudinal axis is offset from the plane by a first distance, and the second position along the longitudinal axis is offset from the plane by a second distance. The joint structure according to claim 4 , wherein the first distance is equal to the second distance. The joint structure of claim 4 , wherein the first distance is different from the second distance. 7 . The joint structure according to claim 1 , wherein at least one of the first edge portion and the second edge portion of the first guide channel includes a rounded portion.

8. The joint structure of claim 1, wherein the first link and the second link contact each other along complementary rolling contact surfaces, the complementary rolling contact surfaces comprising an at least partially cylindrical surface profile.

9. The joint structure of claim 8, wherein the first link and the second link include interengaging features that prevent the rolling contact surfaces from sliding relative to each other.

10. A joint arrangement according to claim 9, wherein in an articulated state of the joint, the actuation element is located radially outwardly from the interengaging features.

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