Low-friction small medical tool with easy-to-assemble members

Abstract

The invention relates to a low-friction small medical tool with easy-to-assemble members. The friction medical device includes a first link, a second link, and a tension element. The first link is coupled to the instrument shaft and defines a first guide path within the first link. The second link is rotatable through a range of angles relative to the first link. A distal end portion of the second link is rotatably coupled to the tool element. A curvilinear guide path is defined within the second link between the tool element and the first guide path. The curvilinear guide surface of the second link defines a portion of a second guide path. A first portion of the tension element is parallel to a centerline of the first guide path and a second portion is coupled to the tool element. A third portion of the tension element between the first and second portions is in contact with the curvilinear guide surface through a portion of the angular range.

Description

[0001] This application is a divisional application of Chinese patent application 201980024569.2 (PCT / US2019 / 020654) entitled “Low-friction small medical tool with easy-to-assemble components” filed on March 5, 2019.

[0002] Related Applications

[0003] This patent application claims the benefit of priority and filing date to U.S. Provisional Patent Application No. 62 / 639,631 (filed on March 7, 2018), entitled “LOW-FRICTION, SMALL PROFILE MEDICAL TOOLS HAVING EASY-TO-ASSEMBLE COMPONENTS”, which is incorporated herein by reference in its entirety. Background Art

[0004] Embodiments described herein relate to grasping tools, more particularly to medical devices, and still more particularly to endoscopic tools. More particularly, embodiments described herein relate to low friction tools and devices including roller-assisted tension members that can be used, for example, in surgical applications.

[0005] Known techniques for minimally invasive surgery (MIS) employ instruments to manipulate tissues, which can be controlled manually or by computer-assisted teleoperation. A variety of known MIS instruments include a therapeutic or diagnostic end effector (e.g., pliers, cutting tools, or cautery tools) mounted at the distal end of an extension (also referred to herein as a main tube or spindle) on a wrist-shaped mechanism. In an MIS procedure, the end effector, wrist-shaped mechanism, and the distal end of the main tube can be inserted into a small incision or natural orifice of the patient to position the end effector at a work site in the patient's body. An optional wrist-shaped mechanism can be used to change the orientation of the end effector relative to the main tube to perform a desired procedure at the work site. Known wrist-shaped mechanisms generally provide desired degrees of freedom (DOF) for the movement of the end effector. For example, for pliers or other grasping tools, known wrist-shaped mechanisms are generally capable of changing the pitch and yaw of the end effector relative to the main tube. The wrist can optionally provide a roll DOF for the end effector, or the roll DOF can be achieved by rolling the main tube. The end effector may optionally have additional mechanical DOFs, such as gripping or knife blade motion. In some cases, the wrist and end effector mechanical DOFs may be combined. For example, U.S. Pat. No. 5,792,135 (filed May 16, 1997) discloses a mechanism in which the wrist and end effector gripping DOFs are combined.

[0006] To achieve the desired movement of the wrist mechanism and the end effector, known instruments include a tension element (e.g., cables, cable / hypotube combinations, tension bands) that extends through the main tube of the instrument and connects the wrist mechanism to a transmission (also referred to herein as a back-end mechanism). The back-end mechanism moves the cables to operate the wrist mechanism. For teleoperation systems, the back-end mechanism is motor-driven and can be operably coupled to a processing system to provide a user interface for the physician to control the instrument.

[0007] Patients benefit from the continuous efforts to improve the effectiveness of MIS methods and tools. For example, reducing the size and / or operating footprint of the main tube and wrist mechanism can allow a smaller entry incision, thereby reducing the negative effects of surgery, such as pain, scarring, and undesirable healing time. However, it can be challenging to produce small-diameter medical devices that achieve the clinically desired functions of minimally invasive procedures. Specifically, simply reducing the size of known wrist mechanisms by "scaling down" components will not lead to effective solutions due to the inability to scale with the required components and material properties. For example, the effective implementation of the wrist mechanism may be complicated because the cables must be carefully routed through the wrist mechanism to maintain cable tension throughout the range of motion of the wrist mechanism, and to minimize the interaction (or coupling effect) of one rotation axis with another rotation axis. Further, pulleys and / or contoured surfaces are generally required to reduce cable friction, which extends the life of the instrument and allows operation without applying excessive force to the cables or other structures in the wrist mechanism. The increased localized forces that may be generated by smaller structures (including cables and other components of the wrist mechanism) may result in undesirable lengthening of the cable during storage and use (eg, "stretching" or "creep"), shortened cable life, etc.

[0008] Further, some medical devices have end effectors that require electrical energy to perform clinical functions such as desiccation, hemostasis, cutting, dissection, drainage, incision, tissue destruction, cauterization, and vessel sealing. Therefore, known devices include one or more conductors routed through a wrist mechanism to the portion of the end effector to be powered. It may be difficult to assemble all components of the wrist mechanism, drive cables, and wires into a small diameter (e.g., less than about 10 mm) while maintaining the necessary strength and functionality of these components.

[0009] In addition to reducing the size of medical devices, it is also desirable to develop low-cost instruments that can be effectively disposable (i.e., intended to be used only once at an economic cost). Using such instruments, each MIS procedure can be performed with a new sterilized instrument, which eliminates the cumbersome and expensive instrument reuse cleaning and sterilization procedures. However, many current instrument designs are expensive to produce, so for economic reasons, these instruments are sterile reprocessed for multiple surgical procedures. In part, the cost of these instruments may be due to the fact that the multi-strand tungsten cable and hypotube portions bear the operating load.

[0010] In some cases, known wrist mechanisms utilize multiple pairs of cables to provide control to move the wrist mechanism within various ranges of motion, including yaw, pitch, and roll movement of the wrist mechanism relative to the main tube. These conventional wrist mechanisms use a pair of pitch cables coupled together to form a cable loop to provide pitch control for the wrist mechanism. The placement of individual cables in such known wrist mechanisms can enhance pitch control, but can also limit movement of the pitch cables during pitch movement and increase friction associated with actuating pitch movement. Further, the inclusion of cable guides and connection features of these mechanisms can also increase the size of the wrist mechanism or make it difficult to reduce its size and footprint.

[0011] Additionally, known wrist mechanisms may be difficult to assemble. For example, the assembly procedure of some known wrist mechanisms may include performing a cable crimping procedure to axially connect a pair of cables to one another, thereby forming a cable loop, and then coupling the pair of cables to the wrist mechanism, wherein the crimp is retained in a pocket formed in the wrist mechanism. Although crimping and connecting the cables to one another prior to installation may avoid damage associated with the crimping operation, the installation of the cable loop along with the installation of an attached cable crimp may complicate the installation of the cable loop and increase undesired bending or damage to the cable loop during installation.

[0012] Therefore, there is a need for improved endoscopic tools. The improvements may include a wrist mechanism having a reduced size, reduced number of parts, lower material cost, and increased strength of a tensile element that operates with low friction during use. Additionally, the improvements may allow for ease of assembly, including installation of a tensile element in a wrist mechanism to axially connect two or more individual tensile elements while avoiding adversely affecting the integrity of the tensile element due to bending, twisting, or other effects during installation. Summary of the invention

[0013] This section introduces certain aspects of the embodiments described herein to provide a basic understanding. This section is not an extensive overview of the inventive subject matter and is not intended to identify key or critical elements or to delineate the scope of the inventive subject matter.

[0014] In some embodiments, a low-friction medical device includes a first link, a second link, and a tension element. The first link is connected to the instrument shaft and defines a first guide path therein. The second link has a proximal portion and a distal portion. The second link can rotate relative to the first link through a certain angle range. The distal portion of the second link is connected to a tool element, and the tool element can rotate around a second axis relative to the second link. A second guide path is defined within the second link, between the tool element and the first guide path. The second link includes a curved guide surface that defines a portion of the second guide path. The tension element has a first tension element portion, a second tension element portion, and a third tension element portion between the first tension element portion and the second tension element portion. The first tension element portion is within the first guide path, and the second tension element portion is connected to the tool element. The third tension element portion contacts the curved guide surface throughout a portion of the angle range. The first tension element portion is parallel to the centerline of the first guide path.

[0015] In some embodiments, a low friction medical device includes a first link, a second link, and a tension element. The first link is coupled to an instrument shaft and defines a first guide path. The second link is coupled to the first link and is rotatable relative to the first link about a first axis. The second link defines a second guide path, a holding pocket, a connection path, and an assembly path. The connection path extends through a portion of the second link between the second guide path and the holding pocket. The wall of the second link surrounds a portion of the connection path. A centerline of the connection path and a centerline of the second guide path define a first plane within the second link. The assembly path extends through a portion of the second link into the holding pocket. The centerline of the assembly path is not parallel to the centerline of the connection path in a second plane that is not parallel to the first plane. The tension element has a first tension element portion, a second tension element portion, and a holding element coupled to the second tension element portion. The first tension element portion is configured to: (A) be inserted through the assembly path along the centerline of the assembly path, and (B) be rotated until the first tension element portion is within the second guide path. The holding element is held within the holding pocket after the first tension element portion is rotated, so that the movement of the tension element relative to the second link is limited. The second link is configured to rotate relative to the first link about the first axis when the first tension member portion moves within the second guide path.

[0016] After reading the following drawings and detailed description, other medical devices, related components, medical device systems and / or methods according to the embodiments will be or become apparent to those skilled in the art. It is intended that all such additional medical devices, related components, medical device systems and / or methods included in this description are within the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1is a plan view of a minimally invasive teleoperated medical system according to an embodiment, which is being used to perform a medical procedure such as surgery.

[0018] Figure 2 yes Figure 1 A perspective view of an optional auxiliary unit of the minimally invasive teleoperated surgical system is shown.

[0019] Figure 3 yes Figure 1 A perspective view of a user control console of a minimally invasive tele-operated surgical system is shown.

[0020] Figure 4 yes Figure 1 A front view of a manipulator unit including a plurality of instruments of a minimally invasive teleoperated surgical system is shown.

[0021] Figure 5 is a diagrammatic perspective view of a portion of an instrument of a surgical system in a first position according to an embodiment.

[0022] Fig. 6A It is first-oriented Figure 5 Diagrammatic top view of the device portion shown.

[0023] Figure 6B yes Figure 5 The device part shown Fig. 6A A magnified view of area H is shown.

[0024] Figure 7 It is of the second orientation Figure 5 Diagrammatic top view of the device portion shown.

[0025] Figures 8A-8B is a diagrammatic illustration of a portion of an instrument system according to an embodiment.

[0026] Fig. 9 is a perspective view of instruments of a surgical system in a first orientation according to an embodiment.

[0027] Fig.10 Is Fig. 9 An enlarged perspective view of the distal portion of the instrument indicated by area Z is shown.

[0028] Fig.11 Shown in exploded view Fig.10 A perspective view of the distal portion of the instrument.

[0029] Fig.12 yes Fig.11 An enlarged perspective view of a portion of a tensile element is shown.

[0030] Fig.13 yes Fig.10A perspective view of the distal portion of the instrument is shown with the second link removed to expose a portion of the tension element.

[0031] Fig.14A is along Fig. 9 The first orientation is taken by the line YY shown in FIG. Fig.10 A side view of a distal portion of the instrument is shown with the first link and tension element removed to expose a portion of the guide path.

[0032] Fig. 14B Is Fig.14A The area K shown indicates the first orientation Fig.10 An enlarged side view of the distal portion of the instrument.

[0033] Fig.15A It is first-oriented Fig.10 A top view of the distal portion of the instrument.

[0034] Fig. 15B and 15C yes Fig.15A The enlarged top view of the portion indicated by areas L and M is shown, showing Fig.10 The thimble structure of the second link of the instrument.

[0035] Fig.16A is along Fig.15A The line RR shown is cut Fig.10 Cross-sectional view of the distal portion of the instrument.

[0036] Fig. 16B Is Fig.16A An enlarged cross-sectional view of the distal portion of the instrument indicated by area S is shown.

[0037] Fig.17A is along Fig.15A The second orientation is shown taken along line RR. Fig.10 Cross-sectional view of the distal portion of the instrument.

[0038] Fig. 17B is along Fig.15A The third orientation is shown by the line RR. Fig.10 Cross-sectional view of the distal portion of the instrument.

[0039] Fig.18 According to the implementation method Fig. 9 An enlarged perspective view of the distal portion of another instrument, indicated by area Z, is shown.

[0040] Fig.19 is along Fig. 9 The first orientation intercepted by the line YY Fig.18 Side view of the distal portion of the instrument.

[0041] Fig. 20 It is first-oriented Fig.18 A side view of a distal portion of the instrument is shown with the first link removed to expose a portion of the tension element.

[0042] Fig.21 It is of the second orientation Fig.18 A side view of a distal portion of the instrument is shown with the first link removed to expose a portion of the tension element.

[0043] Fig. 22 yes Fig.18 A side view of the distal portion of the instrument showing the Fig. 20 The first orientation is superimposed Fig.21 and a second orientation, and both are shown with the first link removed to expose a portion of the tensile element.

[0044] Fig.23 yes Fig. 20 The area T shown indicates the first orientation Fig.18 An enlarged side view of the distal portion of the instrument.

[0045] Fig.24 yes Fig.21 The area U indicates the second orientation of Fig.18 An enlarged side view of the distal portion of the instrument.

[0046] Fig.25 is along Fig. 20 The first orientation of the line XX is shown Fig.18 Cross-sectional view of the distal portion of the instrument.

[0047] Fig.26 is a diagrammatic front view of a portion of an instrument of a surgical system in a first orientation according to an embodiment.

[0048] Fig. 27 is based on Fig.26 The first orientation observed by line NN Fig.26 A diagrammatic side view of a portion of the instrument is shown and is shown without the tension member to expose a path formed therein.

[0049] Fig.28 is along Fig. 27 The first orientation is intercepted by the line QQ shown Fig.26 and 27 A diagrammatic cross-sectional view of a portion of the device is shown and is shown without a tension member to expose a path formed therein.

[0050] Fig.29 is along Fig. 27The first orientation is taken by the line PP shown Fig.26 and 27 A diagrammatic cross-sectional view of a portion of the device is shown and is shown without a tension member to expose a path formed therein.

[0051] Fig.30 yes Fig.26 and 27 A diagrammatic top view of a distal portion of a tension element of the instrument portion is shown.

[0052] Fig.31A yes Fig.26 and 27 A diagrammatic top view of a distal portion of a tensile element of an instrument portion is shown illustrating an installation bend in the tensile element as part of an installation method according to an embodiment.

[0053] Fig.31B and 31C is along Fig. 27 The line PP shown is taken Fig.26 and 27 Diagrammatic cross-sectional views of the device parts shown, and each together with Fig.30 A top view of a distal portion of a tension element is shown to illustrate an installation method according to an embodiment.

[0054] Fig.32 is an enlarged perspective view of a distal portion of the instrument in a first orientation according to an embodiment.

[0055] Fig.33 yes Fig.32 An enlarged perspective view of a distal portion of the instrument is shown with some of the tension element, first link, and pulley removed to expose a portion of the second link.

[0056] Fig.34 Is Fig.33 The area F indicated Fig.32 and 33 An enlarged perspective view of a portion of the apparatus.

[0057] Fig.35 It is first-oriented Fig.32 Side view of the distal portion of the instrument.

[0058] Fig.36 It is first-oriented Fig.32 A side view of the second link of the apparatus.

[0059] Fig.37 is along Fig.36 The first orientation is intercepted by the line VV shown in FIG. Fig.32 A bottom view of the second link of the device.

[0060] Fig.38 yes Fig.32 A perspective view of the third tension element of the apparatus.

[0061] Fig.39 and 40 It is first-oriented Fig.32 A perspective view of a portion of a second link and a pitch tension element of an apparatus illustrating the installation of the pitch tension element.

[0062] Fig.41 and 42 yes Fig.32 The second connecting rod portion of the device and Fig.38 The line WW shown is used for observation Fig.38 and 39 A top cross-sectional view of a pitch tension element of the pitch tension element installation is shown. DETAILED DESCRIPTION

[0063] The embodiments described herein can be advantageously used for various grasping, cutting and manipulation operations associated with minimally invasive surgery. Specifically, the instruments described herein can be low-cost disposable instruments that are useful for use in only one procedure. As described herein, the instrument includes one or more cables (which serve as tension elements) that can be moved to actuate the end effector with multiple degrees of freedom. In addition, the cables can include areas with larger cross-sectional areas to promote increased strength, or the cables can be wrapped or bent to allow efficient routing within a miniaturized wrist assembly.

[0064] In some embodiments, a low-friction medical device includes a first link, a second link, and a tension element. The first link is connected to the instrument shaft and defines a first guide path therein. The second link has a proximal portion and a distal portion. The second link can rotate relative to the first link around a first axis through a certain angle range. The distal portion of the second link is connected to a tool element, and the tool element can rotate relative to the second link around a second axis. A curved guide path is defined between the tool element and the first guide path within the second link. The second link includes a curved guide surface that defines a portion of the second guide path. The tension element has a first tension element portion, a second tension element portion, and a third tension element portion between the first tension element portion and the second tension element portion. The first tension element portion is within the first guide path, and the second tension element portion is connected to the tool element. The third tension element portion contacts the curved guide surface throughout a portion of the angle range. The first tension element portion is parallel to the centerline of the first guide path.

[0065] In some embodiments, the centerline of the first guide path is offset from the centerline of the shaft by a first distance, and the curvilinear guide surface is characterized by a radius about the first axis. In such embodiments, the radius is equal to the first distance. In some embodiments, the centerline of the first guide path is offset from the centerline of the shaft by a first distance, and the curvilinear guide surface is characterized by a radius of curvature that defines a first portion of the second guide path. The center of the radius of curvature is offset from the shaft by a second distance, and the second distance is equal to the sum of the radius of curvature and the first distance.

[0066] In some embodiments, the tension element includes a fourth tension element portion between the first tension element portion and the third tension element portion. The fourth tension element portion is parallel to the centerline of the first guide path throughout the angular range. In some embodiments, the curved guide surface of the second link is the outer surface of a pulley coupled to the second link, or the curved guide surface is a wall of the second link. In some embodiments, the curved guide surface is a first curved guide surface, and the second link includes a second curved guide surface. The first curved guide surface includes the outer surface of a pulley coupled to the second link and forms a first portion of the second guide path. The second curved guide surface defines a second portion of the second guide path. The portion of the angular range is the first portion, and the third tension element portion is in contact with the outer surface of the pulley throughout the first portion of the angular range. The third tension element portion is in contact with the second curved guide surface throughout the second portion of the angular range. The fourth tension element portion is parallel to the centerline of the first guide path throughout the first angular range and the second angular range. In some embodiments, when the second link is in a first orientation relative to the first link, the third tension element portion is spaced apart from the outer surface of the pulley and in contact with the second curved guide surface. The third tension element is spaced apart from the second curvilinear guide surface and in contact with an outer surface of the pulley when the second link is in a second orientation relative to the first link.

[0067] In some embodiments, the centerline of the first guide path is offset from the centerline of the shaft by a distance, and the outer surface of the pulley defines a pulley radius equal to the distance. In some embodiments, the second curvilinear guide surface is characterized by a radius of curvature, and the distance is less than the sum of the pulley radius and the radius of curvature. In some embodiments, the distance is a second distance, the center of the radius of curvature is offset from the centerline of the shaft by a first distance, and the first distance is equal to the sum of the second distance and the radius of curvature.

[0068] In some embodiments, the low friction medical device includes a first link, a second link, and a tension element. A first guide path is defined in the first link, and the centerline of the first guide path is offset by a certain distance from the centerline of the shaft. The second link has a proximal portion and a distal portion. The proximal portion of the second link is rotatably connected to the first link, and the second link can rotate around the first axis relative to the first link through a certain angle range. The distal portion of the second link is rotatably connected to the tool element, and the tool element can rotate around the second axis relative to the second link. A second guide path is defined between the tool element and the first guide path in the second link. The second link includes a curved guide surface that defines a portion of the second guide path. The curved guide surface is characterized by a radius around the first axis. The radius is equal to the distance that the centerline of the first guide path is offset from the centerline of the shaft. The tension element has a first tension element portion, a second tension element portion, and a third tension element portion between the first tension element portion and the second tension element portion. The first tension element portion is in the first guide path, and the second tension element portion is connected to the tool element. The third tension element portion is in contact with the curvilinear guide surface throughout at least a portion of the angular range.

[0069] In some embodiments, the low friction medical device includes a first link, a second link, and a tension element. A first guide path is defined in the first link. The centerline of the first guide path is offset by a first distance from the centerline of the shaft. The second link has a proximal portion and a distal portion. The proximal portion of the second link is rotatably coupled to the first link. The second link can rotate through a certain angle range around the first axis relative to the first link. The distal portion of the second link is rotatably coupled to the tool element, and the tool element can rotate around the second axis relative to the second link. A second guide path is defined between the tool element and the first guide path in the second link. The second link includes a curved guide surface that defines a portion of the second guide path. The curved guide surface is characterized by a radius of curvature. The center of the radius of curvature is offset by a second distance from the centerline of the shaft. The second distance is equal to the sum of the radius of curvature and the first distance. The tension element has a first tension element portion, a second tension element portion, and a third tension element portion between the first tension element portion and the second tension element portion. The first tension element portion is in the first guide path, and the second tension element portion is coupled to the tool element. The third tension element portion is in contact with the curvilinear guide surface throughout at least a portion of the angular range.

[0070] In some embodiments, the tool element has a pulley portion that is coupled to a distal portion of the second link by a pin. The second portion of the tension element is wound around the pulley portion offset from the pin so that when the tension element is moved, the tool element rotates relative to the second link about the second axis. The second portion of the tension element is parallel between the curved guide surface of the second link and the pulley portion of the tool element.

[0071] In some embodiments, a medical device includes a first link, a second link, and a tension element. The first link is coupled to an instrument shaft and defines a first guide path. The second link is rotatably coupled to the first link to rotate relative to the first link about a first axis. The second link defines a second guide path, a holding pocket, a connection path, and an assembly path. The connection path extends through a portion of the second link between the second guide path and the holding pocket. The wall of the second link surrounds a portion of the connection path. A centerline of the connection path and a centerline of the second guide path define a first plane within the second link. The assembly path extends through a portion of the second link into the holding pocket. The centerline of the assembly path is not parallel to the centerline of the connection path in a second plane that is not parallel to the first plane. The tension element has a first tension element portion, a second tension element portion, and a holding element coupled to the second tension element portion. The first tension element portion is configured to: A) be inserted through the assembly path along the centerline of the assembly path, and B) rotate until the first tension element portion is within the second guide path. The holding element is held within the holding pocket after the first tension element portion rotates, so that movement of the tension element relative to the second link is limited. The second link is further configured to rotate relative to the first link about the first axis when the first tension element portion moves within the second guide path.

[0072] In some embodiments, the tension element is a cable and the retaining element is a cable crimp. In some embodiments, the cable crimp is configured to have an angular torsion from a relaxed state relative to a longitudinal axis of the tension element at the cable crimp during installation. In some embodiments, the first tension element portion is rotated through an installation angle of approximately 90 degrees. In some embodiments, an elongated slot is defined within the second link, and the cable crimp is configured to slide through the elongated slot and into a retaining pocket when the tension element portion is rotated. In some embodiments, the cable crimp is configured to return to a relaxed state without angular torsion after installation. In some embodiments, the size of the retaining pocket is larger than the size of the connection path. In some embodiments, the second plane intersects the first plane. In some embodiments, the centerline of the assembly path and the centerline of the connection path form an insertion angle between 5 degrees and 45 degrees. In some embodiments, the retaining element includes a swage connector attached to the tension element.

[0073] In some embodiments, a medical device includes a first link, a second link, and a tension element. The first link is coupled to an instrument shaft and defines a first guide path therein. The second link is rotatably coupled to the first link to rotate relative to the first link about a first axis. The second link defines a second guide path, a holding pocket, a connection path, and an assembly path. The connection path extends through a portion of the second link between the second guide path and the holding pocket. A first wall of the second link defines an elongated slot that opens into the holding pocket. A second wall of the second link defines a distal boundary of the holding pocket. A connection path centerline and a centerline of the second guide path define a first plane within the second link. The assembly path extends through the portion of the second link into the holding pocket. An assembly path centerline of the assembly path is non-parallel to the connection path centerline in a second plane that is non-parallel to the first plane. The tension element has a first tension element portion, a second tension element portion, and a holding element coupled to the second tension element portion. The first tension element portion is configured to A) be inserted through the elongated slot and the assembly path along the assembly path centerline, and B) rotate until the first tension element portion is within the second guide path. The retaining element is retained within the retaining pocket after the first tensile element portion rotates such that movement of the tensile element relative to the second link is limited. The second link is configured to rotate relative to the first link about the first axis when the first tensile element portion moves within the second guide path.

[0074] In some embodiments, a method of assembling a portion of a wrist assembly is provided, wherein the wrist assembly includes a first link and a second link. The first link defines a first guide path, and the second link is rotatably coupled to the first link to rotate about a first axis relative to the first link. The method includes inserting a first end portion of a tension element through an assembly path defined within the second link. The assembly path extends through a portion of the second link into a retaining pocket defined by the second link. The tension element includes a second end portion and a retaining element coupled to the second end portion. The method further includes, after the insertion, rotating the portion of the tension element about a rotational axis that is not parallel to a longitudinal axis of the first end portion of the tension element. The rotation causes the first end portion of the tension element to be within a second guide path and a connection path defined by the second link. The connection path extends through a portion of the second link between the second guide path and the retaining pocket. An assembly path centerline of the assembly path is not parallel to a connection path centerline of the connection path.

[0075] In some embodiments, the method of assembling portions of a wrist assembly further comprises inserting a first end portion of the tensile element into the first guide path. In some embodiments, rotating comprises rotating the tensile element through an angle of 5 to 45 degrees.

[0076] As used herein, the term "about" when used in conjunction with a referenced numerical indication means the referenced numerical indication plus or minus up to 10% of the referenced numerical indication. For example, the expression "about 50" encompasses a range of 45 to 55. Similarly, the expression "about 5" encompasses a range of 4.5 to 5.5.

[0077] The term "flexible" in connection with a component such as a mechanical structure, component, or component assembly should be interpreted broadly. Essentially, the term means that the component can be repeatedly bent and returned to its original shape without damage to the component. Certain flexible components may also be elastic. For example, if a component (e.g., a flexure) has the ability to absorb energy when it is elastically deformed and then release the stored energy (i.e., return to its original state) when unloading, the component is said to be elastic. Many "rigid" objects have a slight inherent elastic "bendability" due to the properties of the material, although such objects are not considered "flexible" when the term is used in this article.

[0078] Flexible components may have infinite degrees of freedom (DOF). Flexibility is an extended property of the object and therefore depends on the material from which the object is formed as well as certain physical properties of the object (e.g., cross-sectional shape, length, boundary conditions, etc.). For example, the flexibility of an object can be increased or decreased by selectively including materials having a desired elastic modulus, flexural modulus, and / or hardness in the object. The elastic modulus is an intensive (i.e., intrinsic) property of the constituent material and describes the tendency of an object to deform elastically (i.e., non-permanently) in response to an applied force. In the presence of the same applied stress, a material with a high elastic modulus will not deflect as much as a material with a low elastic modulus. Thus, the flexibility of an object can be reduced, for example, by introducing a material with a relatively high elastic modulus into the object and / or constructing the object with a material with a relatively high elastic modulus. Examples of such components include closed, bendable tubes (composed of, for example, Polymers, soft rubbers, etc.), helical coil springs, etc., which can be bent into a variety of simple or compound curves, usually without significant cross-sectional deformation.

[0079] Other flexible components can approximate such infinite DOF components by using a series of closely spaced members that resemble a serial arrangement of short connected links like a snake-like "vertebrae". In this vertebral arrangement, each member is a short link in a kinematic chain, and a movable mechanical constraint (e.g., pin hinge, cup and ball, living hinge, etc.) between each link can allow relative movement of one DOF (e.g., pitch) or two DOF (e.g., pitch and yaw) between the links. The short flexible member can act as and be molded into a mechanical constraint (joint) that provides one or more DOF between two links in a kinematic chain - even though the flexible member itself can be a kinematic chain made of several connected links with multiple DOF or infinite DOF links.

[0080] As used in this specification and the appended claims, the word "distal" refers to a direction approaching a working site, while the word "proximal" refers to a direction away from a working site. Thus, for example, the end of a tool closest to the target tissue would be the distal end of the tool, while the end opposite the distal end (i.e., the end manipulated by the user or coupled to the actuation shaft) would be the proximal end of the tool.

[0081] Further, the specific words selected to describe one or more embodiments and optional elements or features are not intended to limit the present invention. For example, spatial 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 of the example in the figure. These spatial relative terms are intended to cover the different positions (i.e., translation placement) and orientations (i.e., rotation placement) of the device in use or operation except the position and orientation shown in the drawings. For example, if the device in the drawings is flipped, the element described as "below" or "below..." of other elements or features will then be "above" or "above" of other elements or features. Therefore, the term "below" can cover the position and orientation of the upper and lower parts at the same time. The device can be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein are interpreted accordingly. Similarly, the description of the movement along (translation) and around (rotation) various axes includes various spatial device positions and orientations. The combination of the position and orientation of the subject defines the posture of the subject.

[0082] Similarly, unless the context indicates otherwise, geometric terms such as "parallel," "perpendicular," "circular," or "square" are not intended to require absolute mathematical precision. Instead, such geometric terms allow for variations resulting from manufacturing or equivalent functions. For example, if an element is described as "circular" or "generally circular," this description still encompasses components that are not strictly circular (e.g., components that are slightly elliptical or have many sides and are polygonal).

[0083] In addition, unless the context indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms as well. The terms "comprising", "including", "having", etc. specify the presence of the features, steps, operations, elements, components, etc., but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, or groups.

[0084] Unless otherwise indicated, the terms "device," "medical device," "apparatus," and variations thereof are used interchangeably.

[0085] The main one used is the da Aspects of the present invention are described herein with reference to an implementation of a surgical system. An example of such a surgical system is the da Vinci Surgical System (Model IS4000) and da Vinci Surgical System (Model IS3000). However, the skilled person will appreciate that the inventive aspects disclosed herein may be implemented and realized in a variety of ways, including computer-assisted, non-computer-assisted, and hybrid combinations of manual and computer-assisted embodiments and implementations. Implementation on surgical systems (e.g., Model IS4000, Model IS3000, Model IS2000, Model IS1200) is presented only as an example, and should not be considered to limit the scope of the inventive aspects disclosed herein. Where applicable, aspects of the invention can be implemented and realized in relatively small, handheld, manually operated devices as well as relatively larger systems with additional mechanical support.

[0086] Figure 11010 is a plan view example of a computer-assisted remote operation system. A medical device is shown, which is a minimally invasive robotic surgery (MIRS) system 1000 (also referred to herein as a minimally invasive remote operation surgery system) for performing minimally invasive diagnostic or surgical procedures on a patient P lying flat on an operating table 1010. The system can have any number of components, such as a user control unit 1100 for use by a surgeon or other technical clinician S during the procedure. The MIRS system 1000 may further include a manipulator unit 1200 (commonly referred to as a surgical robot) and an optional auxiliary equipment unit 1150. The manipulator unit 1200 may include an arm assembly 1300 and a tool assembly removably connected to the arm assembly. While the surgeon S observes the surgical site and controls the movement of the tool 1400 through the control unit 1100, the manipulator unit 1200 can manipulate at least one removably connected tool assembly 1400 (also referred to herein as a "tool") through a minimally invasive incision or natural orifice in the body of the patient P. The image of the surgical site is obtained through an endoscope (not shown), such as a stereo endoscope, which can be manipulated by the manipulator unit 1200 to orient the endoscope. The auxiliary equipment unit 1150 can be used to process the image of the surgical site for subsequent display to the surgeon S through the user control unit 1100. The number of tools 1400 used at one time will generally depend on the diagnostic or surgical procedure and the space limitations in the operating room, as well as other factors. If it is necessary to replace one or more of the instruments 1400 being used during the procedure, the assistant removes the instrument 1400 from the manipulator unit 1200 and replaces it with another instrument 1400 from the tray 1020 in the operating room. Although shown as being used in conjunction with instrument 1400, any instrument described herein can be used in conjunction with MIRS1000.

[0087] Figure 2 11 is a perspective view of the control unit 1100. The user control unit 1100 includes a left-eye display 1112 and a right-eye display 1114 for presenting a coordinated stereoscopic view of the surgical site with depth perception to the surgeon S. The user control unit 1100 further includes one or more input control devices 1116, which in turn cause the manipulator unit 1200 ( Figure 1 The input control device 1116 provides at least the same degrees of freedom as the instrument 1400 with which it is associated, thereby providing the surgeon S with telepresence, or the perception that the input control device 1116 is integral with (or directly connected to) the instrument 1400. In this way, the user control unit 1100 provides the surgeon S with a strong sense of directly controlling the instrument 1400. Therefore, position, force, and tactile feedback sensors (not shown) can be used to transmit position, force, and tactile sensations from the instrument 1400 back to the surgeon's hand through the input control device 1116.

[0088] The user control unit 1100 Figure 1 The user control unit 1100 is shown as being in the same room with the patient, so that the surgeon S can directly monitor the procedure, be present in person if necessary, and talk directly with the assistant, rather than through a telephone or other communication medium. However, in other embodiments, the user control unit 1100 and the surgeon S can be located in a different room from the patient, a completely different building, or other location away from the patient, to achieve a remote surgical procedure.

[0089] Figure 3 is a perspective view of the auxiliary equipment unit 1150. The auxiliary equipment unit 1150 can be connected to the endoscope (not shown) and can include one or more processors to process the captured images for subsequent display, such as via the user control unit 1100 or on another suitable display at a local and / or remote location. For example, in the case of using a stereoscopic endoscope, the auxiliary equipment unit 1150 can process the captured images to present a coordinated stereoscopic image of the surgical site to the surgeon S via the left eye display 1112 and the right eye display 1114. Such coordination can include alignment between relative images and can include adjusting the stereo working distance of the stereoscopic endoscope. As another example, image processing can include using predetermined camera calibration parameters to compensate for imaging errors of the image capture device, such as optical aberrations.

[0090] Figure 4 A front perspective view of the manipulator unit 1200 is shown. The manipulator unit 1200 includes components (e.g., walls, connectors, motors, sensors, etc.) to provide manipulation of the instrument 1400 and an imaging device (not shown), such as a stereo endoscope, for capturing images of the procedure site. Specifically, the instrument 1400 and the imaging device can be manipulated by a remote operating mechanism having multiple joints. In addition, the instrument 1400 and the imaging device are positioned and manipulated through an incision or natural orifice of the patient P in such a way that the kinetic remote center of motion remains at the incision or orifice. In this way, the incision size can be minimized.

[0091] Figure 5 , 6A, 6B and 7 are illustrated examples of various portions of instrument 2400 according to an embodiment. In some embodiments, instrument 2400 or any component thereof is optionally a component of a surgical system that performs a minimally invasive surgical procedure and may include a manipulator unit, a series of kinematic connectors, a series of cannulas, etc. Instrument 2400 (and any instrument described herein) may be used in any suitable surgical system (such as the MIRS system 1000 shown and described above). Instrument 2400 includes a wrist assembly 2500, at least one tensioning element 2420, and a tool element 2462. Although only one tensioning element 2420 is shown, one or more additional tensioning elements or one or more additional tool elements may be included. As described herein, instrument 2400 is configured such that movement of tensioning element 2420 produces movement of wrist assembly 2500 (such as Fig. 6A and 7 As shown), movement of tool element 2462 (as Figure 5 exemplified), or movement of the wrist assembly 2500 and movement of the tool element 2462.

[0092] The wrist assembly 2500 includes a proximal first link 2510 and a distal second link 2610. The first link 2510 has a proximal portion 2511 and a distal portion 2512. The proximal portion 2511 is coupled to an instrument shaft (not shown). Figure 5-7 The instrument shaft is not shown in the figure, but the proximal portion 2511 can be coupled to any suitable instrument shaft, such as the instrument shaft 4410 ( Fig. 9). In addition, the proximal portion 2511 of the first link 2510 can be coupled to the instrument shaft via any suitable mechanism (e.g., welding, interference fit, adhesive, etc.). As described below, the distal portion 2512 is rotatably coupled to the second link 2610. In this manner, the first link 2510 and the second link 2610 form a wrist assembly 2500 having a first rotation axis A1 (which serves as a pitch axis; the term pitch is arbitrary), and the second link can rotate through a certain angular range of the wrist assembly relative to the first link about the first rotation axis A1. The proximal first link 2510 defines a first guide path 2515 extending from its proximal portion 2511 to its distal portion 2512 within and through the first link. At least a portion of the first guide path 2515 is parallel to the centerline CL1 of the shaft (not shown), but offset relative to the centerline of the shaft, as discussed further below. Thus, the centerline CL2 of the first guide path 2515 is offset from the centerline CL1 of the shaft by a first distance d1. In some embodiments, the centerline CL1 of the shaft is coaxial with the centerline of the first link 2510 and intersects the first rotation axis A1. Thus, in such embodiments, the centerline CL2 of the first guide path 2515 is offset from the first rotation axis A1 of the shaft by a first distance d1.

[0093] The second link 2610 has a proximal portion 2611 and a distal portion 2612. As described above, the proximal portion 2611 is rotatably coupled to the distal portion 2512 of the first link 2510 to form a wrist-like joint. The rotation axis A1 is located on the centerline CL1 of the shaft (and in some embodiments, the first link 2510) and along the centerline CL3 of the second link 2610 (see Figure 7 ).exist Figure 5 , 6A In the first orientation shown in FIG6B , the shaft centerline CL1 (also the centerline of the first link 2510) and the centerline CL3 of the second link are collinear. Figure 7In the second orientation shown, the axial centerline CL1 of the first link 2510 forms a certain angle (i.e., a pitch angle) with the centerline CL3 of the second link. In some embodiments, the proximal portion 2611 can be connected to the distal portion 2512 via a pin-type joint (such as the pin-type joint between the proximal clevis 220 and the distal clevis 230 shown and described in U.S. Pat. No. US8,821,480B2 (filed on July 16, 2008), entitled "Four-Cable Wrist with Solid Surface Cable Channels", which is incorporated herein by reference in its entirety). In other embodiments, the proximal portion 2611 can be connected to the distal portion 2512 via a mating disc surface (such as the type shown and described in U.S. patent application publication No. US2017 / 0120457A1 (filed on February 20, 2015), entitled "Mechanical Wrist Joints with Enhanced Range of Motion, and Related Devices and Methods," which is incorporated herein by reference in its entirety).

[0094] The distal end portion 2612 of the second link 2610 includes a connector 2680 coupled to the tool element 2462 so that the tool element 2462 can rotate relative to the wrist assembly 2500 about the second rotation axis A2 through a certain angular range. Figure 5As shown, the second rotation axis A2 (also referred to as the yaw axis or grip axis) is not parallel to the first rotation axis A1. As described herein, the axis A2 acts as a yaw axis (the term yaw is arbitrary) when the tool element 2462 rotates together with another tool element (not shown, but the second tool element can be optionally included in the instrument 2400), and acts as a grip axis (grip axis) when the tool element rotates opposite to another tool element (not shown). Therefore, the instrument 2400 provides up to three degrees of freedom (i.e., pitch rotation around the first rotation axis A1, yaw rotation around the second rotation axis A2, and gripping movement around the second rotation axis A2). Although the second rotation axis A2 is shown as perpendicular to the first rotation axis A1, in other embodiments, the second rotation axis A2 can be offset from the first rotation axis A1 by any suitable angle. The connector can be any suitable connector to rotatably connect the tool element 2462 to the second link 2610 to form a tool joint. For example, in some embodiments, the connector 2680 may include a U-clip and a pin, such as the pin-type connector shown and described in U.S. Patent No. 9,204,923 (filed on July 16, 2008), entitled "Medical Instrument Electronically Energized Using Drive Cables", which is incorporated herein by reference in its entirety. In other embodiments, the connector 2680 may include a compliant mechanism, such as the compliant mechanism shown and described in International Publication No. WO 2016 / 123139 A2 (filed on January 26, 2016), entitled "Rolling-Contact Joint Mechanisms and Methods", which is incorporated herein by reference in its entirety.

[0095] The second link 2610 defines within and through the second link a second guide path 2615 extending from the first guide path 2515 at a proximal portion 2611 thereof to the tool element 2462 at a distal portion 2612 thereof. The second link includes an inner guide surface 2616 that defines a portion of the second guide path and is located within the second guide path 2615 relative to the second link 2610. Although the inner guide surface 2616 is shown as being located at the proximal portion 2611 of the second link 2610 along the second guide path 2615, in other embodiments, the inner guide surface 2616 can be at any suitable location or define any suitable portion of the second guide path 2615. The inner guide surface 2616 is curved relative to the first rotation axis A1 such that the inner guide surface has a radius of curvature R relative to the first rotation axis A1. 弯曲, the radius of curvature R 弯曲 along Fig. 6A and 7 The direction CC shown extends throughout the rotational angle range of the wrist assembly 2500 about the first rotational axis A1. 弯曲 centered about the first axis of rotation A1, but in other embodiments, the radius of curvature of the inner guide surface 2616 can be centered about any suitable location. As discussed further below, the inner guide surface 2616 and the radius of curvature R 弯曲 Configured to keep the portion of the tension element 2420 located within the first guide path 2515 centered thereon to reduce frictional contact of the tension element 2420 during movement of the second link 2615 relative to the first link 2515, movement of the tool element 2462 relative to the second link 2615, or movement of both the tool element 2462 and the second link 2610.

[0096] The second link further includes an outer guide surface 2619 that defines a portion of the second guide path 2615 and is located on an exterior of the second guide path 2615 relative to the second link 2610. Although the outer guide surface 2619 is shown as being located within the second guide path 2615 near the distal portion 2612, in other embodiments, the outer guide surface 2619 can be at any suitable location or define any suitable portion of the second guide path 2615. As discussed further below, the outer guide surface 2619 biases the tension element 2420 into contact with the inner guide surface 2616. Additionally, the distal outer guide surface is configured to align the tension element 2420 with the tool element 2462 for attachment thereto.

[0097] Tension element 2420 has a proximal portion 2421, a distal portion 2422 coupled to tool element 2462, a distal center portion 2423, and a proximal center portion 2425. Proximal portion 2421 is located within a portion of first guide path 2515 of first link 2510. Distal center portion 2423 is between the distal portion and proximal center portion 2425, and is located within second guide path 2615 of second link 2610. Proximal center portion 2425 is between distal center portion 2423 and proximal portion 2421. When second link 2610 is in Figure 5 , 6A6B, at least the inner guide surface 2616 of the second link 2610 contacts the distal center portion 2423 of the tension element 2420. Similarly, the distal center portion 2423 of the tension element 2420 contacts the inner guide surface 2616 throughout a portion of the angular range of motion of the second link 2610 relative to the first link 2510. The inner guide surface 2616 guides the path of the tension element 2420 to Fig. 6A 24. In the first orientation shown, and when the second link 2610 is rotated relative to the first link 2510 in the direction CC shown, it transitions within the second curvilinear guide path 2615. Specifically, the inner guide surface 2616 is sized and positioned so that the proximal portion 2421, the proximal center portion 2425, or the proximal portion 2421 and the proximal center portion 2425 of the tension element are aligned with the centerline CL2 of the first guide path 2515. Similarly stated, this arrangement causes the proximal portion 2421, the proximal center portion 2425, or the proximal portion 2421 and the proximal center portion 2425 of the tension element to be parallel to the centerline CL2. In addition, the radius of curvature R of the inner guide surface 2616 is 弯曲 The proximal portion 2421, the proximal central portion 2425, or the proximal portion 2421 and the proximal central portion 2425 of the tension element remain parallel to the centerline CL2 within the range of movement of the second link 2610 relative to the first link 2510 in the direction CC. As a result, the tension element 2420 can move within the first guide path 2515 in the direction indicated by the arrow AB without contacting the surface within the first guide path. In this way, the frictional contact caused by the movement of the tension element 2420 is reduced within the angular range of movement in the direction CC.

[0098] In some embodiments, the inner guide surface 2616 has a radius of curvature R about the first rotation axis A1. 弯曲 , which is less than or equal to the distance d1, so that the proximal portion 2421, the proximal central portion 2425, or the proximal portion 2421 and the proximal central portion 2425 of the tension member remain parallel to the centerline CL2 within the range of motion of the second link 2610. Although shown as a single radius of curvature R 弯曲 , but in other embodiments, the inner guide surface 2616 can be a curved surface characterized by multiple different radii of curvature.

[0099] As described below in conjunction with other embodiments herein, in some embodiments, a second tension element (not shown) can be similarly offset in opposite directions relative to the longitudinal centerline CL1 of the first link 2510 and the first axis A1 to impart rotation in direction CC.

[0100] The proximal portion 2421 of the tension element 2420 extends proximally from the wrist assembly 2500, through the instrument shaft (not shown), and is coupled to an actuator (not shown) at the proximal end of the instrument. The actuator (which acts as a transmission) can move the proximal portion 2421 of the cable by any suitable mechanism to produce a resulting movement (or force) at the distal portion 2422 of the cable (e.g., Figure 5 and 6A AB in FIG. 26 ). In some embodiments, the actuator of the instrument 2400 is motor-driven and is therefore suitable for a robotic or teleoperated surgical system. The proximal central portion 2425 and the distal central portion 2423 of the tension element 2420 are disposed within the second guide path 2615, and the distal portion 2422 of the cable is coupled to the tool element 2462. In this manner, as described herein, movement of the tension element 2420 can produce rotation of the tool element 2462, rotation of the second link 2610, or rotation of the tool element 2462 and the second link 2610. The distal portion 2422 of the cable 2420 can be coupled to the tool element 2462 by any suitable mechanism. For example, in some embodiments, the distal portion 2422 can be coupled to the tool element 2462 by a pin or protrusion that engages with (or is received in) a connecting portion of the tool element 2462. In other embodiments, the distal portion 2422 can be coupled to the tool element 2462 via an adhesive. In yet another embodiment, the distal portion 2422 of the tension element can be wrapped around the pulley portion of the tool element 2462.

[0101] refer to Figure 5 , the tool element 2462 is coupled to the wrist assembly 2500 and rotates relative to the wrist assembly about the second rotation axis A2. Specifically, the first and second guide paths 2515, 2615 are offset from the second rotation axis A2 by a distance d2. In this way, applying tension to the tension element 2420 in the proximal direction (indicated by arrow AB as direction B) generates a torque on the tool element 2462 about the second rotation axis A2, which causes the tool element 2462 to rotate relative to the second link 2610, as shown in FIG. Figure 5DD in . In this way, the distal portion (e.g., engagement portion) of tool element 2462 can engage or manipulate target tissue during a surgical procedure. Tool element 2462 (or any tool element described herein) can be any suitable medical tool element. For example, in some embodiments, tool element 2462 (or any tool element described herein) can include an engagement surface that acts as a gripper, a cutter, a tissue manipulator, etc. In other embodiments, tool element 2462 (or any tool element described herein) can be an energized tool element for a cauterization procedure. Although only one tool element 2462 is shown, in other embodiments, instrument 2400 includes two mobile tool elements that cooperate to perform a gripping or shearing function. In this way, tool element 2462 can form part of an end effector for surgical instrument 2400.

[0102] like Figure 7 As shown, the second link 2610 defines a longitudinal centerline CL3 that intersects the first rotation axis A1. Figure 5 , 6A and 6B), the longitudinal centerline CL1 of the first link 2510 and the longitudinal centerline CL3 of the second link 2610 are collinear (and Figure 5 When the second link 2610 rotates relative to the first link 2510 (i.e., pitches), the longitudinal centerline CL1 of the first link 2510 and the longitudinal centerline CL3 of the second link form a pitch angle. The range of motion angles in the through direction CC includes Figure 7 At the high pitch angles shown, the tension element 2420 remains aligned with the centerline CL2 of the first guide path 2515 without frictionally contacting the surface of the first link 2510 within the first guide path.

[0103] Reference again Figure 7 , when the instrument is in a high pitch orientation, the reduced amount of frictional contact between the tension element 2420 and the components of the wrist assembly 2500 allows the cable 2420 to move in the direction AA, thereby moving the tool element 2462 in an efficient manner when in a high pitch orientation, and with a reduced likelihood that the tension element 2420 will bind. This allows the tool element 2462 to move throughout a range of pitch orientations (e.g., at 0 degrees ( Fig. 6A ) and 90 degrees ( Figure 7 ), a pitch angle between 0 and 45 degrees, a pitch angle between 0 and 60 degrees).

[0104] In some embodiments, the tension element 2420 (and any tension element described herein) can be formed as a cable made of tungsten or stainless steel to provide sufficient strength, flexibility, and durability. In some embodiments, the cable can be made of a plurality of filament braids to provide strength and flexibility. In some embodiments, the cable can be made of 150 to 350 braids of 0.018 mm to 0.025 mm (0.0007 inches to 0.001 inches) diameter tungsten wire, providing a cable having an outer diameter of 0.356 mm to 0457 mm (0.014 inches to 0.018 inches).

[0105] In some embodiments, the instrument 2400 can include any suitable tension element. For example, in some embodiments, the instrument 2400 (and any instrument described herein) can include a tension element having any suitable cross-sectional shape. For example, in some embodiments, the instrument 2400 (and any instrument described herein) can include a tension band of the type shown and described in U.S. Patent Application No. 62 / 598,620 (December 14, 2017), entitled "Medical Tools Having Tension Bands", which is incorporated herein by reference in its entirety. In some embodiments, such a band (and any tension element described herein) can have a trapezoidal shape. In other embodiments, such a band (and any tension element described herein) can include a slightly curved surface. In addition, such a band (and any tension element described herein) can be composed of any suitable material. For example, in some embodiments, such a band (and any tension element described herein) can be composed of a series of laminates bonded together (e.g., via an adhesive). The laminate can be composed of any suitable material (including tungsten, steel, or any suitable polymer).

[0106] Although the first link 2510 and the second link 2610 are shown as having a rectangular cross-sectional shape, in other embodiments, the first link 2510, the second link 2610, or the first link 2510 and the second link 2610 can have any suitable cross-sectional shape. For example, in some embodiments, the first link 2510, the second link 2610, or the first link 2510 and the second link 2610 can have a substantially circular cross-sectional shape (i.e., the wrist assembly 2500 can be substantially cylindrical).

[0107] Although the second link 2610 is shown and described as having an inner surface 2616 (i.e., a surface located on the interior of the second guide path 2615), in other embodiments, the second link 2610 can have a curvilinear surface in any suitable location within (or defining any portion of) the second guide path 2615. For example, in some embodiments, the second link 2610 can include a curvilinear surface located on the exterior of the second guide path (i.e., an outer guide surface) that contacts a portion of the tension element 2420 such that the proximal portion 2421, the proximal central portion 2425, or both the proximal portion 2421 and the proximal central portion 2425 of the tension element remain parallel to the centerline CL2.

[0108] In some embodiments, the inner surface 2616 (or any of the surfaces within the second guide path 2615 or the first guide path 2515) can be coated, treated, or otherwise created to have a low friction surface. For example, in some embodiments, the inner surface 2616 (or any of the surfaces within the second guide path 2615 or the first guide path 2515) can be characterized by a coefficient of friction of less than 0.1. In some embodiments, the inner surface 2616 (or any of the surfaces within the second guide path 2615 or the first guide path 2515) can be coated with a friction reducing composition, such as a nitride coating.

[0109] In some embodiments, the first link 2510, the second link 2610, or any link described herein can include rollers, bearings, or other friction reducing mechanisms within the first guide path 2515, the second guide path 2615, or any guide path described herein. For example, in some embodiments, the inner surface 2616 can be the outer surface of a pulley coupled to the second link 2610. In other embodiments, the first link 2515, the second link 2615, or any link described herein can include rollers of the type shown and described in U.S. Provisional Patent Application Docket No. ISRG10440PROV / US, entitled "Low-Friction Medical Tools Having Roller-Assisted Tension Members" (filed on the same date as the present application), which application is incorporated herein by reference in its entirety.

[0110] Although the instrument 2400 is shown and described as including a single tool element 2462 and a single tension element (i.e., cable 2420), in other embodiments, the instrument may include any suitable number of tension elements or tool elements. For example, in some embodiments, the instrument may include four tension elements (or portions of tension elements). Fig. 8A3400, according to an embodiment. Instrument 3400 includes wrist assembly 3500, first tension element 3420, second tension element 3440, and end effector 3460. Instrument 3400 is configured so that movement of various portions of first tension element 3420 and second tension element 3440 can produce movement of wrist assembly 3500 around pitch axis A1, movement of end effector 3460 around yaw axis A2, grasping motion of end effector 3460, or any combination of these motions.

[0111] The wrist assembly 3500 (which acts as a joint assembly) includes a first link 3510 and a second link 3610. The first link 3510 is coupled to an instrument shaft (not shown) of the type shown and described herein. The second link 3610 has a proximal portion and a distal portion. The proximal portion is rotatably coupled to the first link 3510 to form a wrist assembly 3500 having a first axis of rotation A1 (which acts as a pitch axis, the term pitch being arbitrary), and the second link 3610 can rotate relative to the first link 3510 around the first axis of rotation A1. The wrist assembly 3500 can include any suitable coupling mechanism. For example, in some embodiments, the second link 3610 can be coupled to the first link 3510 via a pin-type joint of the type shown and described herein. In other embodiments, the second link 3610 can be coupled to the first link 3510 via a mating disk surface of the type shown and described herein.

[0112] The distal portion of the second link 3610 is coupled to the end effector 3460. More specifically, the distal portion of the second link 3610 is coupled to the pulley portion 3467 of the first tool element 3462 and the pulley portion 3487 of the second tool element 3482. This arrangement allows each of the tool element 3462 and the tool element 3482 to rotate about the second rotation axis A2 relative to the wrist assembly 3500. The second rotation axis A2 is not parallel to the first rotation axis A1 and acts as a yaw axis (the term yaw is arbitrary) when the tool elements rotate together, and also acts as a gripping axis when the tool elements rotate opposite to each other. Thus, the instrument 3400 provides up to three degrees of freedom (i.e., pitch motion about the first rotation axis A1, yaw rotation about the second rotation axis A2, and gripping motion about the second rotation axis A2). Although the end effector 3460 is shown as being coupled to the second link 3610 via a pin connection, in other embodiments, the end effector 3460 can be coupled to the wrist assembly 3500 by any suitable mechanism.

[0113] The end effector includes a first tool element 3462 and a second tool element 3482. The first tool element 3462 includes a contact portion 3464 and a pulley portion 3467, and the second tool element 3482 includes a contact portion 3484 and a pulley portion 3487. The contact portion 3464 and the contact portion 3484 are each configured to engage or manipulate the target tissue during a surgical procedure. For example, in some embodiments, the contact portion may include an engagement surface that acts as a grasper, a cutter, a tissue manipulator, etc. In other embodiments, the contact portion may be an energized tool element for a cauterization procedure. As described above, the pulley portion 3467 and the pulley portion 3487 are each rotatably coupled to the second link 3610 so that the tool element 3462 can rotate relative to the wrist assembly 3500 via the second rotation axis A2. The pulley portion may include a contact surface around which the corresponding tension element (i.e., the first tension element 3420 and the second tension element 3440) is wound. The first tool element 3462 and the second tool element 3482 (or any tool elements described herein) may be any suitable tool elements of the type shown and described herein.

[0114] The first tension element 3420 (which may be a belt or cable) has a first proximal portion 3421, a second proximal portion 3431, and a distal portion 3422. As shown, the distal portion 3422 is wrapped around the pulley portion 3467 of the first tool element 3462. In this manner, the first proximal portion 3421 and the second proximal portion 3431 each extend through the first link 3510 and into the instrument shaft (not shown). In addition, the first proximal portion 3421 and the second proximal portion 3431 are each coupled to an actuator (not shown) that can move each proximal portion (as indicated by the series of arrows labeled pitch, yaw, and grip). When the wrist assembly 3500 is in a Fig. 8A In the first orientation shown, first distal guide post 3617 is attached to second link 3610 adjacent first middle portion 3423 of first tension member 3420, which first middle portion 3423 extends between first proximal portion 3421 and distal portion 3422 of the first tension member. When wrist assembly 3500 is in the first orientation, an outer surface of first distal guide post 3617 contacts first middle portion 3423 of first tension member 3420. When wrist assembly 3500 is in the first orientation, Fig. 8A In the first orientation shown, first proximal guide post 3522 is attached to first link 3510 adjacent second intermediate portion 3433 of first tension member 3420, which extends between second proximal portion 3431 and distal portion 3422 of the first tension member. An outer surface of first proximal guide post 3522 contacts second intermediate portion 3433 of first tension member 3420 when wrist assembly 3500 is in the first orientation.

[0115] The second tension element 3440 (which may be a belt or cable) has a third proximal portion 3441, a fourth proximal portion 3451, and a distal portion 3442. As shown, the distal portion 3442 is wrapped around the pulley portion 3487 of the second tool element 3482. In this manner, the third proximal portion 3441 and the fourth proximal portion 3451 each extend through the first link 3510 and into the instrument shaft (not shown). In addition, the third proximal portion 3441 and the fourth proximal portion 3451 are each coupled to an actuator (not shown) that can move each proximal portion (as indicated by the series of arrows labeled pitch, yaw, and grip). When the wrist assembly 3500 is in a Fig. 8A In the first orientation shown, the second proximal guide post 3532 is attached to the first link 3510 adjacent to the fourth middle portion 3443 of the second tension element 3440, which extends between the fourth proximal portion 3451 and the distal portion 3442 of the second tension element. When the wrist assembly 3500 is in the first orientation, the outer surface of the second proximal guide post 3532 contacts the fourth middle portion 3443 of the second tension element 3440. When the wrist assembly 3500 is in the first orientation, the outer surface of the second proximal guide post 3532 contacts the fourth middle portion 3443 of the second tension element 3440. Fig. 8A In the first orientation shown, second distal guide post 3627 is attached to second link 3610 adjacent third intermediate portion 3453 of second tension element 3440, which extends between third proximal portion 3441 and distal portion 3442 of the second tension element. An outer surface of second distal guide post 3627 contacts third intermediate portion 3453 of second tension element 3440 when wrist assembly 3500 is in the first orientation.

[0116] In some embodiments, the first tension element 3420 or the second tension element 3440 (or both) can be integrally constructed such that the first proximal portion, the second proximal portion, and the distal portion are all within a single element. However, in other embodiments, the first tension element 3420 or the second tension element 3440 (or both) can include multiple separately constructed components (for example, the first proximal portion 3421 can be constructed separately from the second proximal portion 3431). In addition, the first tension element 3420 or the second tension element 3440 (or both) can have any suitable shape as described herein. In some embodiments, the first tension element 3420 or the second tension element 3440 (or both) can have a varying cross-sectional area. In some embodiments, the first tension element 3420 or the second tension element 3440 (or both) can be composed of a series of laminates bonded together (for example, via an adhesive). The laminate can be composed of any suitable material, including tungsten, steel, or any suitable polymer. In some embodiments, first tension member 3420 and second tension member 3440 may be configured as steel cables.

[0117] Changing the pitch, yaw, or grip of the instrument 3400 generally requires movement or action applied to each of the four proximal portions (the first proximal portion 3421, the second proximal portion 3431, the third proximal portion 3441, and the fourth proximal portion 3451), respectively. Movement of the tension element portions can generally be performed one at a time or simultaneously in any desired combination to change the pitch, yaw, and grip of the instrument 3400. For example, a pitch axis rotation causes the second link 3610 to rotate about the first rotation axis A1 (the pitch axis), as shown by arrow MM. With respect to clockwise rotation about the pitch axis A1, the actuator (not shown) pulls (i.e., moves proximally) the same length of the first proximal portion 3421 and the second proximal portion 3431, while releasing (i.e., allowing distal movement) the same length of the third proximal portion 3441 and the fourth proximal portion 3451. This is exemplified by the arrow labeled Pitch.

[0118] The first proximal portion 3421 and the second proximal portion 3431 apply a force to the second link 3610 at a moment arm defined by a curvilinear guide path through the wrist assembly 3500. Similarly stated, the first link 3510 and the second link 3610 can define one or more curvilinear guide paths that are offset relative to the pitch axis A1 to generate a torque about the pitch axis A1. The curvilinear guide path can be any curvilinear guide path described herein (e.g., the curvilinear guide path shown and described in conjunction with the wrist assembly 2500 or the wrist assembly 4500). Similarly, with respect to the counterclockwise rotation of the second link 3610 about the pitch axis A1, the actuator pulls (i.e., moves proximally) the same length of the third proximal portion 3441 and the fourth proximal portion 3451, while releasing (i.e., allowing distal movement) the same length of the first proximal portion 3421 and the second proximal portion 3431.

[0119] The yaw rotation is a rotation of the first tool element 3462 and the second tool element 3482 in the same direction and through the same angle around the second rotation axis A2 (yaw axis). Specifically, when the actuator pulls (i.e., moves proximally) a certain length of the first proximal portion 3421 and releases (i.e., allows distal movement) an equal length of the second proximal portion 3431, the first tool element 3462 will rotate clockwise around the yaw axis A2 (see arrow NN). With respect to this rotation, the curved guide path or the pulley surface of the pulley portion 3467 defines a moment arm to which the force transmitted via the first tension element 3420 is applied. The resulting torque causes the first tool element 3462 to rotate clockwise. During this movement, the first proximal portion 3421 and the second proximal portion 3431 each slide within the curved guide path of the second link 3610. If the actuator simultaneously pulls in a certain length of the fourth proximal portion 3451 and releases the same length of the third proximal portion 3441, the second tool element 3482 will rotate clockwise through a certain angle, which is the same angle through which the first tool element 3462 rotated. Therefore, the first tool element 3462 and the second tool element 3482 maintain their relative positions to each other and rotate as a unit through a certain yaw angle. When the actuator pulls in equal lengths of the second proximal portion 3431 and the third proximal portion 3441 while releasing the same lengths of the first proximal portion 3421 and the fourth proximal portion 3451, a counterclockwise rotation of the end effector 3460 is similarly achieved. This is exemplified by the arrow marked yaw.

[0120] The grip rotation is a rotation of the first tool element 3462 and the second tool element 3482 about the yaw axis A2 in opposite directions and through the same angle. To open the grip of the end effector 3460, the actuator pulls the first proximal portion 3421 and the third proximal portion 3441 of equal length, while releasing the second proximal portion 3431 and the fourth proximal portion 3451 of equal length. This causes the first tool element 3562 to rotate in the opposite direction to the second tool element 3482. To close the grip of the end effector, the actuator pulls the second proximal portion 3431 and the fourth proximal portion 3451 of equal length, while releasing the first proximal portion 3421 and the third proximal portion 3441 of equal length. This causes the first tool element 3562 to rotate toward the second tool element 3482. When the contact portions of the tool elements are in contact, the tension in the second proximal portion 3431 and the fourth proximal portion 3451 can be maintained greater than the tension in the first proximal portion 3421 and the third proximal portion 3441 to maintain a desired gripping force.

[0121] The proximal guide posts (the first proximal guide post 3522 and the second proximal guide post 3532) are each coupled to the first link 3510 on opposite sides of the pitch axis A1 between the first tension element 3420 and the second tension element 3440. The outer surface of the first proximal guide post 3522 is at Fig. 8A The second intermediate portion 3433 of the first tension member is contacted when in the orientation shown. Similarly, the outer surface of the second proximal guide post 3532 is Fig. 8A The proximal guide posts 3522, 3532 contact the fourth middle portion 3443 of the second tension element when in the orientation shown. Thus, the outer surfaces of the proximal guide posts 3522, 3532 guide the position and orientation of the first tension element 3420 and the second tension element 3440 as the tension elements move. Thus, the proximal guide posts 3522, 3532 maintain the inner middle portions (the second middle portion 3433 and the fourth middle portion 3443) of the first and second tension elements 3420, 3440 in parallel alignment with the instrument axis regardless of the pitch, yaw and gripping movement of the wrist assembly 3500. Maintaining this parallel alignment prevents interfering contact between the first and second tension elements 3420, 3440 and other objects from occurring during movement of the wrist assembly, which may cause the tension elements to bind or become tangled. Additionally, maintaining this parallel alignment reduces friction of the wrist assembly 3500 during operation by avoiding rubbing or other frictional contact between the first and second tension elements 3420, 3440 and other portions of the wrist assembly 3500 and its components.

[0122] Further, the proximal guide posts 3522, 3532 advantageously reduce friction at high tensile stress locations along the tension elements 3420, 344. Specifically, each of the proximal guide posts 3522, 3532 is located on the opposite side of the pitch pivot A1 on the first link 3510, and the second link 3610 rotates around the pitch pivot A1 to perform pitch movement. When high pitch movement is performed, high tensile stress is applied to the tension elements 3420, 3440 located on the opposite side of the pitch rotation direction. The proximal guide posts 3522, 3532 can reduce friction at high tensile stress locations near the pitch pivot A1, which can reduce wear on the tension elements 3420, 3440 and enhance the operation of the wrist assembly 3500.

[0123] The distal guide posts (the first distal guide post 3617 and the second distal guide post 3627) are each connected to the second link 3610 on the opposite outer sides of the second link 3610. The outer surface of the first distal guide post 3617 is in the Fig. 8A The outer surface of the second distal guide post 3627 contacts the first intermediate portion 3423 of the first tension member when in the orientation shown. Fig. 8A The distal guide posts 3617, 3627 contact the third middle portion 3453 of the second tension element when in the orientation shown. In this way, the outer surface of each of the distal guide posts 3617, 3627 guides the position and orientation of the first tension element 3420 and the second tension element 3440. The distal guide posts 3617, 3627 are coupled to the second link 3610, which rotates during the pitch movement of the wrist assembly 3500. In this way, the distal guide posts 3617, 3627 guide the outer middle portions (third middle portion 3453 and first middle portion 3423) of the first and second tension elements 3420, 3440 during the pitch rotational movement to keep the first and second tension elements 3420, 3440 properly positioned to prevent them from getting stuck on objects and binding or tangling during movement of the wrist assembly. Further, the distal guide posts 3617, 3627 advantageously guide the path of the first and second tension elements 3420, 3440 throughout the range of motion, thereby performing pitch movement with low friction.

[0124] Guide posts 3522, 3532, 3617, and 3627 may be any suitable guide posts of the type shown and described herein. For example, in some embodiments, the radius of any of guide posts 3522, 3532, 3617, and 3627 may be less than the radius of curvature of any guide path defined within wrist assembly 3500. Furthermore, while guide posts 3522, 3532, 3617, and 3627 are shown and described as contacting their corresponding portions of first and second tension elements 3420, 3440, any of guide posts 3522, 3532, 3617, and 3627 may be spaced apart from their corresponding portions of first and second tension elements 3420, 3440 when wrist assembly is in the second configuration.

[0125] Wrist assembly 3500 (and any wrist assembly described herein) may include any suitable structure to define any suitable guide path in which the tension element moves, including utilizing a plurality of guide posts to maintain parallel alignment of the proximal portion of the tension element with its connection in the shaft throughout the various movements of the wrist assembly. For example, referring to Figure 8B In some embodiments, the first link 3510' includes a pair of inner and outer guide posts that together maintain the proximal portion of each tension element aligned parallel to the axis, which can avoid frictional contact between the tension element and part of the wrist assembly during movement.

[0126] The first pair of guide posts includes a first inner guide post 3516' and a first outer guide post 3517' located between the first proximal portion 3421' and the second proximal portion 3431' along the first middle portion 3423' of the first tension element 3420'. The first inner guide post 3516' is located on the inner side of the first middle portion 3423', and the first outer guide post 3517' is located on the outer side of the first middle portion 3423'. In a similar manner, the second pair of guide posts includes a second inner guide post 3521' located on the inner side of the second middle portion 3433' of the first tension element 3420', and a second outer guide post 3522' located on the outer side of the second middle portion 3433'. Further, the third pair of guide posts includes a third inner guide post 3526' located on the inner side of the third middle portion 3443' of the second tension element 3440', and a third outer guide post 3527' located on the outer side of the third middle portion 3443'. Likewise, the fourth pair of guide posts includes a fourth inner guide post 3531 ' located on the inner side of the fourth middle portion 3453' of the second tension element 3420', and a fourth outer guide post 3532' located on the outer side of the fourth middle portion 3453'.

[0127] The guide posts in each pair are co-located along the respective middle portion of the tension element such that each pair forms a goal-post type guide along and on each side of the respective middle portion (3423', 3433', 3443', 3453') that maintains the respective first tension element portion (3421', 3431', 3441' and 3451') in parallel alignment with the respective actuator (not shown). Figure 8B The guide post pairs maintain this parallel alignment in the first orientation shown and in other orientations, as well as during movement of the wrist assembly 3500'. Each of the inner guide posts (3516', 3521', 3526', and 3531') in each pair can be spaced apart from the corresponding outer guide post (3517', 3522', 3527', and 3532') so that the corresponding intermediate portion (3523', 3233', 3443', and 3553') disposed therebetween is spaced apart from the corresponding outer guide post (3517', 3522', 3527', and 3532') when in the first orientation shown and in other orientations, as well as during movement of the wrist assembly 3500'. Figure 8B The first orientation shown does not contact the guide posts and can therefore move freely in the longitudinal direction of the tension elements 3220' and 3420' without frictional contact with the guide posts. In this way, the tension elements 3420' and 3440' can move longitudinally in-line with their longitudinal axes with reduced friction when in the first orientation. Further, when the second link 3610' rotates about the first axis A1' relative to the first link 3510', the guide post pair can keep the portions of the first and second tension elements 3420' and 3440' disposed between the guide post pair and the corresponding actuator (not shown) aligned parallel to the corresponding actuator, which can avoid frictional contact with portions of the wrist assembly 3500 and reduce the possibility of tension element binding.

[0128] Figure 9-1 7 is various views of an instrument 4400 according to an embodiment. In some embodiments, the instrument 4400 or any component thereof is optionally a component of a surgical assembly that performs a minimally invasive surgical procedure and may include a manipulator unit, a series of kinematic connections, a series of cannulas, etc. The instrument 4400 (and any instrument described herein) can be used in any suitable surgical system (such as the MIRS system 1000 shown and described above). The instrument 4400 includes a transmission assembly 4700 (which can act as an actuator mechanism), an instrument shaft 4410, a wrist assembly 4500, and an end effector 4460.

[0129] refer to Fig.10, the instrument 4400 also includes a first tensioning element 4420 and a second tensioning element 4440 that couple the transmission mechanism 4700 to the wrist assembly 4500. The instrument 4400 is configured so that movement of the tensioning elements can produce a rotation of the wrist assembly 4500 about the first rotation axis A1 (i.e., a pitch rotation), a yaw rotation of the end effector 4460 about the second rotation axis A2, a gripping rotation of the tool element of the end effector 4460 about the yaw axis, or any combination of these movements. Changing the pitch, yaw, or grip of the instrument 4400 can be performed by manipulating the four tensioning elements in a manner similar to that described above with respect to the instrument 3500. Therefore, the specific movement of each of the four tensioning elements to achieve the desired movement is not described below. Although shown and described as including two tensioning elements wrapped around the end effector 4480 (resulting in four proximal tensioning element portions (i.e., a four-tensioning element arrangement)), in other embodiments, the instrument 4400 may include additional tensioning elements that individually change the pitch of the instrument 4400.

[0130] The transmission mechanism 4700 generates movement of each of the first tension element 4420 and the second tension element to produce a desired movement (pitch, yaw, or grip) at the wrist assembly 4500. Specifically, the transmission mechanism 4700 includes components and controls to move some tension elements in a proximal direction (i.e., pulling certain tension elements closer) while allowing other tension elements to move distally (i.e., releasing or "paying out") an equal length. In this way, the transmission mechanism 4700 can maintain the desired tension within the tension elements and can ensure that the length of the tension elements is maintained (i.e., equal movement) throughout the range of movement of the wrist assembly 4500. In some embodiments, for example, the transmission assembly 4700 can be any transmission assembly shown and described in International Patent Application No. PCT / US2017 / 062258, entitled "Cable Length Conserving Medical Instrument" (filed on November 14, 2017), which is incorporated herein by reference in its entirety. However, in other embodiments, the length of the tension elements need not be maintained.

[0131] In some embodiments, the transmission mechanism 4700 may include one or more linear actuators that produce translation (linear motion) of a portion of the tension element. Such a transmission mechanism may include, for example, a gimbal, a lever, or any other suitable mechanism to directly pull (or release) the end portion of any tension element. For example, in some embodiments, the transmission mechanism 4700 may include any of the transmission assemblies or components described in U.S. Patent Application Publication No. US2015 / 0047454 A1 (filed on August 15, 2014) entitled "Lever Actuated Gimbal Plate" or U.S. Patent No. US6,817,974B2 (filed on June 28, 2001) entitled "Surgical Tool Having Positively Positionable Tendon-Actuated Multi-Disk Wrist Joint", which are incorporated herein by reference in their entirety. However, in other embodiments, the transmission mechanism 4700 may include a capstan or other motor-driven roller that rotates or "wraps" a portion of any tension element to produce the desired tension element movement. For example, in some embodiments, the back-end mechanism 4700 may include any of the back-end components or members described in U.S. Patent No. 9,204,923 B2 (filed on July 16, 2008), entitled "Medical Instrument Electronically Energized Using Drive Cables," which is incorporated herein by reference in its entirety.

[0132] The instrument shaft 4410 can be any suitable elongated shaft that couples the wrist assembly 4500 to the transmission mechanism 4700. Specifically, the instrument shaft 4410 includes a proximal portion 4411 coupled to a housing of the backend mechanism 4700 and a distal portion 4412 coupled to the wrist assembly 4500. The instrument shaft 4410 defines a channel or series of channels through which the tensioning elements and other components (e.g., electrical wires, ground wires, etc.) can be routed from the transmission mechanism 4700 to the wrist assembly 4500. Although shown as being cylindrical, in other embodiments, the instrument shaft 4410 can have any suitable shape.

[0133] refer to Figure 10-13, wrist assembly 4500 includes a proximal first link 4510 and a distal second link 4610. The first link 4510 has a proximal portion 4511 and a distal portion 4512. The proximal portion 4511 is coupled to the distal portion 4412 of the instrument shaft 4410. The proximal portion 4511 can be coupled to the instrument shaft 4410 via any suitable mechanism. For example, in some embodiments, the proximal portion 4511 can be cooperatively disposed within a portion of the instrument shaft (e.g., via an interference fit). As shown, the proximal portion 4511 can include one or more protrusions, recesses, openings, or connectors that couple the proximal portion 4511 to the instrument shaft. The proximal portion 4511 can be fixedly coupled to the instrument shaft 4410 via an adhesive bond, welding, or any other permanent coupling mechanism (i.e., a coupling mechanism that is not intended to be removed during normal use).

[0134] The distal portion 4512 includes a joint portion 4540 that is rotatably coupled to a mating joint portion 4640 of the second link 4610. In this manner, the first link 4510 and the second link 4610 form a wrist assembly 4500 having a first rotation axis A1 (also referred to as a pitch axis), and the second link 4610 can rotate relative to the first link 4510 about the first rotation axis A1. A pin 4541 extends through the distal joint portion 4540 and the second link joint portion 4640 to rotatably couple the second link 4610 to the first link 4510. Fig.10 As shown, the first link 4510 and the second link 4610 define a longitudinal centerline CL that intersects the pitch axis A1 when the instrument is in an initial (or "straight" configuration).

[0135] refer to Fig.11, a first guide channel 4515, a second guide channel 4520, a third guide channel 4525, and a fourth guide channel 4535 are defined in the first link 4510. The first proximal portion 4421 of the first tension element 4420 is movably disposed in the first guide channel 4515. The first proximal portion 4431 of the second tension element 4440 is movably disposed in the second guide channel 4520. The second proximal portion 4441 of the first tension element 4440 is movably disposed in the third guide channel 4525. The second proximal portion 4451 of the second tension element 4440 is movably disposed in the fourth guide channel 4530. In this way, the portion of the first tension element 4420 coupled to the first tool element 4462 is in separate guide channels. However, in some embodiments, the first guide channel 4515 may be combined with the third guide channel 4525 to form a single channel, and the first proximal portion 4421 and the second proximal portion 4441 of the first tension element 4420 are disposed in the single channel. In this manner, the portion of the second tension element 4440 coupled to the second tool element 4482 is within a separate guide channel. However, in some embodiments, the second guide channel 4520 can be combined with the fourth guide channel 4535 to form a single channel, and the first proximal portion 4431 and the second proximal portion 4451 of the second tension element 4440 are disposed within the single channel.

[0136] The first link 4510 also defines an additional hole or guide channel 4550. The additional guide channel 4550 can contain (or allow passage of) various components of the wrist assembly, such as, for example, electrical wires. In some embodiments, the guide channel 4550 can contain an additional tension element (not shown) that is coupled to the second link 4610 and causes the second link 4610 to rotate relative to the first link 4510 (i.e., pitch rotation) when the tension element is moved. In this manner, the wrist assembly 4500 can be a six-tension element configuration (two tension elements or tension element portions control pitch rotation, and four tension elements or tension element portions control yaw and grip rotation).

[0137] The distal second link 4610 has a proximal portion 4611 and a distal portion 4612. As described above, the proximal portion 4611 includes a joint portion 4640, which is rotatably coupled to the joint portion 4540 of the first link 4510. The distal portion 4612 of the second link 4610 includes a connector 4680, which is coupled to the end effector 4460. In this way, the first tool element 4462 and the second tool element 4482 can rotate relative to the second link 4610 about the second rotation axis (also referred to as the yaw axis) A2. The connector 4680 is a pin-type connector and includes a pin 4683, which is supported by (and disposed in) a pin opening 4682. In some embodiments, connector 4680 may include any of the structures and features of a pin-type connector shown and described in U.S. Pat. No. 9,204,923 B2 (filed July 16, 2008), entitled "Medical Instrument Electronically Energized Using Drive Cables," which is incorporated herein by reference in its entirety. Fig.10 As shown, the second rotation axis A2 (also called the yaw axis) is not parallel to the pitch axis A1. Therefore, the instrument 4400 provides up to three degrees of freedom (i.e., pitch motion around the first rotation axis A1, yaw rotation around the second rotation axis A2, and gripping motion around the second rotation axis A2).

[0138] refer to Fig.11 , 14A , 14B, 15A-C, the second link 4610 defines a first sleeve structure 4660 and a second sleeve structure 4665. The first sleeve structure 4660 and the second sleeve structure 4665 are each formed as a raised structure disposed on opposite side portions of the second link 4610, and the raised structures each extend laterally outward from the longitudinal centerline CL of the second link 4610 (see Fig.15A Each of the first and second sleeve structures 4660, 4665 includes a smooth, contoured outer side surface 4661, 4662 that extends substantially around the periphery of the respective first and second sleeve structures 4660, 4665 (see Fig.14A ). The first and second sleeve structures 4660, 4665 are disposed on opposite side portions of the second link 4610 so that the contoured outer side surfaces 4661, 4662 each extend around opposite ends of the joint portion 4640 connected to the joint portion 4540 of the first link, and each outer side surface extends around the first rotation axis A1.

[0139] The contoured outer side surfaces 4661, 4662 of the first and second sleeve structures 4660, 4665 are configured to serve as support surfaces for the tension elements 4420, 4440, which can protect the tension elements from bending or kinking at high load bearing areas within the second link 4610. As discussed below, the contoured outer side surfaces 4661, 4662 are also configured to help guide the tension elements 4420, 4440 through the curvilinear guide paths 4615, 4620 defined in one side of the second link 4610 of the wrist assembly 4500 (see Fig. 14B ), and through a similar curvilinear guide path on the opposite side of the second link (not shown). Fig. 15B and 15C , each of contoured outer side surfaces 4661, 4662 is shaped to include a groove that can enhance retention of the portion of tension elements 4420, 4440 that contacts the contoured outer side surface. The radius of curvature of any contact point along contoured outer side surfaces 4661, 4662 with a portion of one of tension elements 4420, 4440 can be reduced to an effective radius of curvature R 弯曲 OK. Fig.15A and 15B As shown, the effective radius of curvature R at any point along the contoured outer surface 4661, 4662 弯曲 is the sum of the current radius of curvature within the groove at that point along the contoured outside surface and half the thickness (ie, radius) of the tensile element.

[0140] refer to Fig.16A and 16B , this arrangement of the first and second sleeve structures 4660, 4665 allows the first distal center portion 4423 of the first tension element 4420 and the first distal center portion 4433 of the second tension element 4440 to each contact a portion of the outer side surface 4661 of the first sleeve structure - depending on the orientation of the wrist assembly 4500. Although not shown, the second distal center portion 4443 of the first tension element 4420 and the second distal center portion 4443 of the second tension element 4440 can similarly contact the outer surface 4662 of the second sleeve structure 4665 located on the opposite side of the second link 4610. Therefore, this arrangement provides a sleeve structure that acts to engage and define portions of the guide path for two different tension element portions. As shown in FIG. Fig. 15B and 15B As shown, the effective radius of the proximal end of the contoured outer side surfaces 4661, 4662 of the first and second sleeve structures 4660, 4665 is represented by R 弯曲 are determined, and are selected to produce a desired guidance path, as further described below.

[0141] refer to Fig. 14B, the second link 4610 defines a first curvilinear guide path 4615 and a second curvilinear guide path 4620. The second link 4610 also includes a first guide surface 4616 and a second guide surface 4621, which are portions of the contoured outer surface 4661 of the first sleeve structure 4660. The second link 4610 also includes a third guide surface 4617 aligned with a portion of the first curvilinear guide path 4615, and a fourth guide surface 4622 aligned with a portion of the second curvilinear guide path 4620. The first and second curvilinear guide paths 4615, 4620 (and therefore portions of the first tension element 4420 and the second tension element 4440 therein) are each offset relative to the longitudinal centerline CL and the first rotation axis A1. In this manner, a torque about the first rotation axis A1 is generated by the application of force via the first tension element 4420 or the second tension element 4440. This can cause the second link 4610 to rotate (i.e., pitch) relative to the first link 4510, as shown in FIG. Fig.17A As shown by the arrow OO in the figure, a force is applied through the first tension element 4420, or as Fig. 17B As shown by arrow NN in FIG. 4 , force is applied via second tension element 4440. The offset of the tension element from the longitudinal centerline CL is also based in part on the size of sleeve structure 4660. Fig.16A and 16B As shown, when the device 4400 is in certain orientations, the outer surface 4661 of the sleeve structure 4660 contacts the first central portion 4423 of the first tension element 4420 and the third central portion 4433 of the second tension element 4440. Therefore, the effective radius R of the sleeve structure 4660 is 弯曲 The offset is limited.

[0142] like Fig.13 As shown, end effector 4460 includes a first tool element 4462 and a second tool element 44824. First tool element 4462 includes contact portion 4464 and pulley portion 4467. Contact portion 4463 is configured to engage or manipulate target tissue during a surgical procedure. Although shown as a gripping surface, in other embodiments, contact portion 4464 can be any suitable surface of the type shown and described herein (e.g., a cutter, a tissue manipulator, a cauterization surface, etc.). Fig.10 and 11As shown, the pulley portion 4467 is rotatably coupled to the second link 4610 via the pin 4683. In this way, the first tool element 4462 can rotate around the pin 4683 and relative to the second link 4610 via the second rotation axis A2. In addition, the pulley portion 4467 defines a coupling opening 4472, in which the distal end portion 4422 of the first tension element 4420 is coupled. The outer surface of the pulley portion 4467 is offset relative to the yaw axis A2. In this way, the application of force on the pulley portion 4467 by the first tension element 4420 generates a torque on the first tool element 4462 about the yaw axis A2, which can cause rotation of the first tool element 4462 or application of a gripping force.

[0143] like Fig.13 As shown, the second tool element 4482 includes a contact portion 4484 and a pulley portion 4487. The contact portion 4484 is configured to engage or manipulate target tissue during a surgical procedure. Although shown as a gripping surface, in other embodiments, the contact portion 4484 can be any suitable surface of the type shown and described herein (e.g., a cutter, a tissue manipulator, a cauterization surface, etc.). Fig.10 and 11 As shown, the pulley portion 4487 is rotatably coupled to the second link 4610 via the pin 4683. In this way, the second tool element 4464 can rotate around the pin 4683 and relative to the second link 4610 via the second rotation axis A2. Fig.11 As shown, the pulley portion 4487 defines a coupling opening 4492, and the distal end portion 4432 of the second tension element 4440 is coupled within the coupling opening 4492. The outer surface of the pulley portion 4487 is offset relative to the yaw axis A2. In this way, the application of the force of the second tension element 4440 on the pulley portion 4487 generates a torque about the yaw axis A2 on the second tool element 4482, which can cause rotation of the second tool element 4482 or application of a gripping force.

[0144] like Fig.12As shown, the first tension element 4420 has a first proximal portion 4421, a first proximal central portion 4425, a first distal central portion 4423, and a first distal portion 4422 on one side of the first tension element loop, and a second central portion 4443 and a second proximal portion 4441 together with the first distal portion 4422 on the other side of the first tension element loop. The second tension element 4440 has a third proximal portion 4431, a third proximal central portion 4427, a third distal central portion 4433, and a third terminal portion 4432 on one side of the second tension element loop, and a fourth central portion 4453 and a fourth proximal portion 4451 together with a fourth distal portion on the other side of the second tension element loop. The proximal portions 4421, 4427, 4431, 4437 each extend out of the wrist assembly 4500, through the instrument shaft 4410, and into the transmission mechanism 4700. As described above, the transmission mechanism 4700 can move the proximal portions 4421, 4427, 4431, 4437 to produce a resulting movement (or force) at the corresponding distal portions 4422, 4432 of the tension elements. The tension elements 4420 and 4440 can have any suitable shape. The use of tension elements can provide a low-cost disposable instrument suitable for minimally invasive surgical procedures. In use, the distal portion of the instrument 4400 provides up to three degrees of freedom and can be moved between a variety of different configurations to perform various surgical operations.

[0145] refer to Fig.16A The first proximal central portion 4425 of the first tension element 4420 and the third proximal central portion 4426 of the second tension element 4440 are held in the first and second curved guide paths 4615, 4620 on one side of the second link 4610, as shown in the above combination Fig. 14B The shapes of the first and second curvilinear guide paths 4615, 4620 enable the first tension element 4420 and the second tension element 4440 to be routed through the wrist assembly 4500 in a manner such that the desired bending geometry, tension element tension, etc. are maintained therein during actuation of the instrument 4400. This includes routing the first and second tension elements 4420, 4440 in a low friction, parallel alignment relative to the first and second curvilinear guide paths 4615, 4620, as described below in conjunction with Fig. 16B , 17Aand 17B. Similarly, the second center portion 4443 of the first tension element 4420 and the fourth center portion 4453 of the second tension element 4440 are retained within respective third and fourth curvilinear guide paths (not shown), as described above with respect to the first and second curvilinear guide paths 4615, 4620. The shapes of the third and fourth curvilinear guide paths (not shown) enable the first tension element 4420 and the second tension element 4440 to be routed through the wrist assembly 4500 in a manner that maintains the desired bending geometry, tension element tension, etc. during actuation of the instrument 4400. This also includes routing the first and second tension elements 4420, 4440 in a low friction manner, as described below in conjunction with Fig. 16B , 17A and 17B with respect to the first and second curvilinear guide paths 4615, 4620, 4616. As described above, the distal portion 4422 is coupled to the first tool element 4462, and the distal portion 4433 is coupled to the second tool element 4482—via a pin or swage coupling (i.e., within coupling openings 4472, 4492). In this manner, as described herein, movement of the tension element (or force applied thereto) can produce pitch, yaw, grip, or any combination of these motions.

[0146] refer to Fig.16A and 16B , the third guide surface 4617 is formed along the distal portion of the first curvilinear guide path 4615 and is bent inwardly relative to the curvilinear guide path 4615, so that the first guide surface 4616 and the third guide surface 4617 are convex relative to each other and relative to the curvilinear guide path 4615. Further, the third guide surface 4617 has an effective radius of curvature R1, which includes the radius of curvature of the third guide surface 4617 plus the thickness of the first tension element 4420 (i.e., the radius of the circular tension element). The third guide surface 4617 is configured to guide the first distal center portion 4423 of the first tension element 4420 through the first guide path 4615 so that the portion of the first tension element 4420 disposed between the first distal end portion 4422 and the first distal center portion 4423 is located at Fig.16A In the first orientation shown and when in Fig.17A The second orientation shown, Fig. 17B In the third orientation shown and orientations therebetween, the third guide surface is aligned parallel to the pulley portion 4467 of the end effector 4460. In this way, the third guide surface can reduce the frictional contact between the first tension element 4420 and the end effector 4460 including the pulley portion 4467 during the movement of the wrist assembly 4500 by maintaining the parallel alignment of the first tension element between the second link 4620 and the end effector 4460. In addition, as described below in conjunction with Fig.17AFurther discussion, the third guide surface is configured to Fig.17A In the second orientation shown, the first distal center portion 4423 of the first tensile member 4420 is guided such that the proximal center portion 4425 remains aligned parallel to the first guide path 4515 of the first link 4510. The fourth guide surface 4622 is also configured to guide a portion of the second tensile member 4440 relative to the second guide path 4620 in a similar manner.

[0147] refer to Fig.16A , 16B and 17B, when the second connecting rod 4610 is in Fig.10 , 16A and the first orientation shown in 16B, and when the second link 4610 is in other orientations (e.g., Fig. 17B 44, the distal center portion 4423 of the tension element 4420 contacts the first guide surface 4616 throughout a portion of the angular range of motion of the second link 4610 relative to the first link 4510. Fig.16A In the first orientation shown and also when the second link 4610 is along the first link 4510 relative to the first link Fig. 17B When rotated in the direction NN shown, the first guide surface 4616 guides the path of the first tension member 4420 transitioning within the second curvilinear guide path 4615. Further, the first guide surface 4616 is configured to do so while also maintaining the first proximal central portion 4425 and the first proximal end portion 4421 of the first tension member 4420 aligned parallel to the centerline CL2 of the first guide path 4515 of the first link 4510.

[0148] Specifically, the first guide surface 4616 is sized and positioned so that the first proximal portion 4421, the first proximal central portion 4425, or the first proximal portion 4421 and the first proximal central portion 4425 of the first tension element 4420 remain aligned parallel to the centerline CL2 of the first guide path 4515 of the first link 4510 throughout a portion of the angular range of motion of the second link 4610 relative to the first link 4510. In this way, the first tension element 4420 can move along the first guide path 4615 within the first tension element 4420. Fig.16A The first guide surface 4616 is configured to move in the direction indicated by the arrow AB without contacting the surface within the first guide path 4515 of the first link. In this way, frictional contact is reduced with respect to movement of the first tension element 4420 within at least the angular range of motion along the direction NN. In some embodiments, the first guide surface 4616 has an effective radius of curvature R about the first rotation axis A1. 弯曲 , the effective radius of curvature R弯曲 equal Fig.16A The distance d1 shown allows the first proximal portion 4421, the first proximal central portion 4425, or the first proximal portion 4421 and the first proximal central portion 4425 of the first tension member to remain parallel to the centerline CL2 within a portion of the range of motion of the second link 4610. Although shown as a single radius of curvature R 弯曲 , but in other embodiments, the first guide surface 4616 can be a curved surface characterized by multiple different radii of curvature.

[0149] refer to Fig.16A and 17A , when the second connecting rod 4610 is in Fig.10 and 16A When the first orientation is shown, and when the second link 4610 is in other orientations (e.g., Fig.17A 440), at least the second guide surface 4621 of the second link 4610 contacts the second distal center portion 4433 of the second tension element 4440. Similarly, the second distal center portion 4433 of the second tension element 4440 contacts the second guide surface 4621 throughout a portion of the angular range of motion of the second link 4610 relative to the first link 4510 (e.g., wrapped around it, such as Fig.17A ). Fig.16A In the first orientation shown, and when the second link 4610 is relative to the first link 4510 along Fig.17A When rotated in the direction OO shown, the second guide surface 4621 guides the path of the second tension element 4440 transitioning within the second curvilinear guide path 4620. Further, the second guide surface 4621 is configured to do so while also maintaining the second proximal central portion 4426 and the second proximal end portion 4431 of the second tension element 4440 aligned parallel to the centerline CL3 of the second guide path 4520 of the first link 4510.

[0150] Specifically, the second guide surface 4621 is sized and positioned so that the second proximal portion 4431, the second proximal central portion 4426, or the second proximal portion 4431 and the second proximal central portion 4426 of the second tension element 4440 remain aligned parallel to the centerline CL3 of the second guide path 4520 throughout a portion of the angular range of motion. Fig.16A The second guide surface 4621 moves in the direction indicated by the arrow AB without contacting the surface within the second guide path. In this way, the frictional contact with respect to the second tension element 4440 moving along the direction OO within at least the range of motion angle is reduced. In some embodiments, the second guide surface 4621 has an effective curvature radius R around the first rotation axis A1.弯曲 , the effective radius of curvature R 弯曲 equal Fig.16A The distance d1 shown allows the second proximal portion 4431, the second proximal central portion 4426, or the second proximal portion 4431 and the second proximal central portion 4426 of the second tension member to remain parallel to the centerline CL3 within a portion of the range of motion of the second link 4610. Although shown as a single radius of curvature R 弯曲 , but in other embodiments, the second guide surface 4626 can be a curved surface characterized by multiple different radii of curvature.

[0151] In use, the wrist assembly 4500 can be moved between various orientations. Fig.17A As shown by arrow OO in FIG. 1 , the wrist assembly 4500 can be moved between the first (or straight) orientation and the second orientation by rotating the second link 4610 relative to the first link 4510 about the first rotation axis A1. Fig. 17B The first rotation axis A1 rotates in the opposite direction as shown by the arrow NN in FIG. Fig. 17B When the wrist assembly 4500 is in the third orientation Fig.16A In the first orientation shown, first tensile element 4420 is within first tensile element path 4615 and second tensile element 4440 is within second tensile element path 4620. More specifically, first central portion 4423 contacts first guide surface 4616 of second link 4610 and outer side surface 4661 of sleeve structure 4660. Second central portion 4433 contacts second guide surface 4621 of second link 4610 and outer side surface 4661 of sleeve structure 4660. When the first tension element 4420 and the second tension element 4440 move in the same direction (for example, to produce a yaw movement of the end actuator 4460), the first distal center portion 4423 and the second distal center portion 4433 will slide against the surface 4461, which causes the first proximal center portion 4425 and the second proximal center portion 4426 of the first and second tension elements 4420, 4440 to be aligned parallel to the center lines CL2, CL3 of the first and second guide paths 4515, 4520 of the first link 4510.

[0152] When the wrist assembly 4500 is in the second orientation ( Fig.17A), the first distal central portion 4423 of the first tension element 4420 remains within the first curvilinear guide path 4615, but is spaced apart from the first guide surface 4616 and is wrapped around and in contact with the third guide surface 4617. In addition, the first distal central portion 4423 is spaced apart from the sleeve structure 4660 and its outer side surface 4661 together with the first guide surface 4616, so that the first distal central portion 4423 is guided primarily by the third curvilinear guide surface 4617 within the first curvilinear guide path 4615.

[0153] The third guide surface 4617 has an effective radius of curvature R1, which includes the radius of curvature of the third guide surface 4617 plus half the thickness of the first tension element 4420 (i.e., the radius of the circular tension element). The effective radius of curvature R1 is configured to Fig.17A In the second orientation shown, the first proximal central portion 4425 of the first tensile member 4420 is aligned parallel to the center line CL2 of the first guide path 4515 of the first link 4510. Therefore, the first proximal central portion 4425 and the first proximal end 4421 of the first tensile member 4420 can penetrate the second link 4610 at Fig.17A The second orientation shown is Fig.16A and 16B The first orientation shown, to the following Fig. 17B The angular range of motion between the third orientations shown maintains parallel alignment within the first guide path 4515 of the first link 4510. Thus, through the angular range of motion of the wrist assembly 4500, frictional contact of the first tension element 4420 within the first guide path 4515 of the first link can be avoided, which reduces the overall friction of its movement.

[0154] When the wrist assembly 4500 is in the third orientation ( Fig. 17B ), the second distal central portion 4433 of the second tension element 4440 remains within the second curvilinear guide path 4620 but is spaced apart from the second guide surface 4621. In this way, the distal central portion 4433 wraps around and contacts the fourth guide surface 4622, which thereby guides the distal central portion to maintain the proximal central portion 4426 parallel to the centerline CL3 of the second guide path 4520 of the first link 4510. In addition, the second distal central portion 4433 is spaced apart from the sleeve structure 4660, so that the second distal central portion is guided in the second curvilinear guide path 4620 mainly by the fourth curvilinear guide surface 4622.

[0155] The fourth curvilinear guide surface 4622 has an effective radius of curvature R1, which includes the radius of curvature of the fourth guide surface 4622 plus half the thickness of the second tension element 4440 (i.e., the radius of the circular tension element). The effective radius of curvature R1 is configured to Fig. 17B In the third orientation shown, the second proximal central portion 4426 of the second tension member 4440 is aligned parallel to the center line CL3 of the second guide path 4520 of the second link 4510. Therefore, the second proximal central portion 4426 and the second proximal end 4431 of the second tension member 4440 can penetrate the second link 4610 at Fig.17A The second orientation shown is Fig.16A and 16B The first orientation shown, to Fig. 17B The angular range of motion between the third orientations shown maintains parallel alignment within the second guide path 4520 of the first link 4510. Thus, through the angular range of motion of the wrist assembly 4500, frictional contact of the second tension element 4440 within the second guide path 4540 of the first link can be avoided, which reduces the overall friction of its movement.

[0156] Reference again Fig.16A and 16B The first tension member 4420 and the second tension member 4440 are configured for low friction axial movement when the first proximal portion 4421 and 4431 move according to the above-mentioned actuator (not shown), which causes the first proximal portion to move along Fig.16A Thus, at the proximal end of the sleeve structure including the first and second curved surfaces 4616, 4621, the effective radius R of the outer support wall 4661 of the sleeve structure 4660 is 弯曲 The center lines CL2 and CL3 of the first and second guide paths 4515 and 4520 of the first link 4510 are configured to be offset from the center line CL1 of the shaft by the same distance d1. In other words, the effective radius (ie, R 弯曲 ) is configured to be equal to the offset distance (ie, d1) of the first link guide surfaces 4515, 4520, such that R 弯曲 = d1. This relationship is when the wrist component is Fig.16A and 16B In the first orientation shown, the first and second proximal center portions 4425, 4426 and the first and second proximal end portions 4421, 4431 of the first and second tension elements 4420, 4440 are aligned in parallel with the first and second guide paths 4515, 4520 of the first link 4510 and through the first and second guide paths 4515, 4520 of the first link 4510.

[0157] R弯曲 = d1 is further maintained by: the first distal central portion 4423 contacts the first curved guide surface 4616 ( Fig. 17B ) and in contact with the second curved guide surface 4621 at the second distal central portion 4433 ( Fig.17A ), the second link 4610 rotates relative to the first link 4510 about a partial angle of the first rotation axis A1. This is because the first and / or second curved guide surfaces 4616, 4621 are formed as part of the outer side wall 4661 of the sleeve structure 4460, which has R 弯曲 As its effective radius of curvature, the R 弯曲 = d1 - relative to the first rotation axis A1 located along the shaft centerline CL1. In this way, the first and / or second proximal central portions 4425, 4426 remain aligned parallel to the first and second guide path centerlines CL2 and CL3 in the first link 4510, which are in the second orientation ( Fig.17A ) and the third orientation ( Fig. 17B ) is also offset from the axis centerline by the same distance d1. For example, Fig.17A The second tensile member 4440 is shown wrapped around a portion of the sleeve structure 4660 in a second orientation such that the second distal portion 4433 is aligned with the effective radius R 弯曲 The effective radius R 弯曲 is equal to d1 relative to axis A1 and shaft centerline CL1, thereby maintaining parallel alignment of the second proximal central portion 4426 with the second guide path 4520 through the first link 4510. Likewise, Fig. 17B The second tensile member 4420 is shown wrapped around a portion of the sleeve structure 4660 in the third orientation such that the first distal portion 4423 is aligned with the first distal portion 4423 having an effective radius R 弯曲 The first surface 4616 contacts the effective radius R 弯曲 Equal to d1 relative to axis A1 and shaft centerline CL1 , thereby maintaining parallel alignment of the first proximal central portion 4425 with the first guide path 4515 through the first link 4510 .

[0158] With further reference to FIGS. 16A and 16B, the first tension element 4420 and the second tension element 4440 are further configured to provide low friction axial movement when in the first orientation based on: (i) the effective radius of curvature R1 of the third and fourth curvilinear surfaces 4617, 4622; (ii) the effective radius of curvature R2 of the first and second curvilinear surfaces 4616, 4621. 弯曲 ; and (iii) axis A of R1 R1 The vertical offset distance from the shaft centerline CL1. Fig.16A As shown, the effective radius of curvature R1 of the third and fourth curvilinear surfaces 4617, 4622 each have an axis A about the radius of curvature. R1 , the axis A R1 The wrist is vertically offset from the axial centerline CL1 on the opposite side of the axial centerline by an offset distance d2. Fig.16A The first orientation shown is at a vertical offset distance d2, an effective radius of curvature R1 and a radius of curvature R 弯曲 A relationship is provided between them, so that the vertical offset distance d2 is less than the effective curvature radius R1 plus the curvature radius R 弯曲 The sum (i.e., d2 <R 弯曲 +R1). This relationship of the first orientation ensures that the first and second distal center portions 4423, 4433 of the tension elements 4420, 4440 are guided inwardly toward the centerline CL of the wrist assembly 4500 by guiding the first and second guide paths 4615, 4620, respectively, which is consistent with Fig.16A The axis centerlines CL1 of the first orientation are shown to be simultaneous. The first and second distal center portions 4423, 4433 are guided inwardly within the respective first or second guide paths 4615, 4620 from a point of contact with the first or second curvilinear guide surface 4616, 4621 to a point of contact with the respective third or fourth curvilinear guide surface 4617, 4622. Thus, each of the first and second distal center portions 4423, 4433 is biased to contact the respective first or second curvilinear guide surface 4616, 4621 and the respective third or fourth curvilinear guide surface 4617, 4622 of the corresponding first or second guide paths 4615, 4620 when in the first orientation, which aligns the first and second proximal center portions 4425, 4426 in parallel with the respective first and second first guide paths 4515, 4420 of the first link 4510.

[0159] like Fig.16A As shown, the second link 4610 is configured to rotate about the first rotation axis A1 relative to the first link 4510. The second link 4610 rotates along the indicated direction OO by an angle θ to rotate from the first orientation to Fig.17A In some embodiments, the angular rotation θ from the first orientation to the second orientation can be the maximum angular rotation θ of the second link 4610 relative to the first link 4510. When the second link 4610 is rotated from the first orientation to the second orientation, the third and fourth curvilinear surfaces 4616, 4621, the corresponding effective radius of curvature R1 and the axis of curvature A R1 The third curved surface 4617 is also rotated about the first axis A1 to rotate by an angle θ. The rotation changes the curvature axis A of the third curved surface 4617. R1 The position and the first orientation of the axis center line CL are Fig.17AThe vertical offset distance d2 of the rotational position of the second orientation shown, which is offset from the axis centerline CL by a vertical distance d2'.

[0160] In an embodiment where the second link 4610 is rotated at a maximum angle Θ to obtain the second orientation, the vertical offset distance d2' of the third guiding surface 4617 from the axis centerline CL to the axis A R1 is equal to the axial offset distance of the centerline CL2 of the first guiding path 4515 in the first link 4510 plus the corresponding radius of curvature R1 of the third guiding surface 4617. In other words, d2' (the vertical offset of the curvature axis at maximum rotation) is equal to the sum of d1 (the vertical offset of the first guiding path) and R1 (the radius of the distal third guiding surface) (i.e., d2' = d1 + R1), which maintains the parallel alignment of the proximal center tension element 4425 and the first guiding path 4515 during maximum angle rotation in the direction OO. However, for Fig.16A the first orientation, d2 (the vertical offset of the curvature axis in the first orientation) is less than the sum of d1 and R1 (i.e., d2 < d1 + R1), which maintains the parallel alignment of the proximal center tension element 4425 and the first guiding path 4515 in this orientation. This is because at the maximum angle of rotation Θ, when in the second orientation, the distal center portion 4423 of the first tension element 4420 remains against the third guiding surface 4617, causing the first proximal center portion 4425 and the first end portion 4421 to be parallel aligned with the first guiding path 4515. Therefore, the first tension element 4420 can move freely longitudinally within the first guiding path 4515 when at its maximum angle of rotation and in the second orientation without frictionally contacting the surfaces within the first guiding path.

[0161] Referring to Fig. 14B and 16B , the sleeve structure 4660 includes a proximal region 4663 and a distal region 4664. The outer wall 4661 of the proximal region 4663 includes a first guiding surface 4616 on one side of the axis centerline CL and a second guiding surface 4621 on the opposite second side of the centerline. Additionally, the proximal region 4663 is curved around the rotational axis A1 according to the radius of curvature R 弯曲 . In contrast, the outer wall 4661 within the distal region 4664 is not curved according to the radius of curvature R 弯曲 . Instead, the outer wall 4661 within the distal region 4664 is configured to have the following profile: generally following the profile of the portions of the first and second tension elements 4420, 4440 that are close to the outer wall when in the Fig. 16B first orientation shown. This profile portion of the outer wall 4661 can provide additional guiding surfaces along the first and second guiding paths 4615 and 4620 to guide the first and tension elements 4420, 4440 during movement within the guiding paths.

[0162] In some embodiments, the sleeve structure can be configured to include a proximal portion 4663 of the sleeve structure 4660 without including a distal portion 4664. Fig. 14B and 16B The sleeve structure 4660 shown may be configured to include a portion of an outer sidewall 4661 forming a first guide surface 4616 and a second guide surface 4621, which is curved to have a radius of curvature R 弯曲 , excluding the outer wall 4661 according to the curvature radius R 弯曲 The remaining portion (and corresponding portion of the sleeve structure 4660) is curved. In other words, the sleeve structure can be configured to have a circular pulley-like shape that can be fixed relative to the second link 4610 or mounted as a pulley to rotate relative to the second link 4610. This embodiment can further avoid potential frictional contact between the tension elements 4420, 4440 and the surfaces provided along the guide paths 4615, 4620 from the distal portion of the sleeve during the longitudinal movement of the tension elements therein. For example, Figure 18-25 Various views of the instrument 5400 are shown according to an embodiment in which the sleeve structure is configured as a pulley that lacks a distal portion and corresponding surface and rotates relative to the second link 5610. Figure 18-25 In addition to the above, the device 5400 generally includes the above combination Figure 10-17B Aspects and features of the apparatus 4400 discussed.

[0163] Similar to instrument 4400, instrument 5400 includes a transmission assembly 5700 (which may function as an actuator mechanism), an instrument shaft 5410, a wrist assembly 5500, and an end effector 5460. Fig.18, the instrument 5400 also includes a first tension element 5420 and a second tension element 5440 that couple the transmission mechanism 5700 to the wrist assembly 5500. The instrument 5400 is configured so that the movement of the cables can produce a rotation of the wrist assembly 5500 about the first rotation axis A1 (i.e., a pitch rotation), a yaw rotation of the end effector 5460 about the second rotation axis A2, a grip rotation of the tool element of the end effector 5460 about the yaw axis, or any combination of these movements. Changing the pitch, yaw, or grip of the instrument 5400 can be performed by manipulating the four cables in a manner similar to that described above with respect to the instruments 3500 and 4500. Therefore, the specific movement of each of the four cables to achieve the desired movement is not described below. Although shown and described as including two cables that are wrapped around the end effector 5460 to produce four proximal cable portions (i.e., a four-cable arrangement), in other embodiments, the instrument 5400 can include additional cables that individually change the pitch of the instrument 5400.

[0164] refer to Fig.18 and 19 , the wrist assembly 5500 includes a proximal first link 5510 and a distal second link 5610. The first link 5510 has a proximal portion 5511 and a distal portion 5512. The proximal portion 5511 is coupled to the distal portion 5412 of the instrument shaft 5410. The proximal portion 5511 can be coupled to the instrument shaft 5410 via any suitable mechanism. For example, in some embodiments, the proximal portion 5511 can be cooperatively disposed within a portion of the instrument shaft (e.g., via an interference fit). As shown, the proximal portion 5511 can include one or more protrusions, recesses, openings, or connectors that couple the proximal portion 5511 to the instrument shaft. The proximal portion 5511 can be fixedly coupled to the instrument shaft 5410 via adhesive bonding, welding, or any other permanent coupling mechanism (i.e., a coupling mechanism that is not intended to be removed during normal use).

[0165] The distal portion 5512 includes a joint portion 5540 that is rotatably coupled to a mating joint portion 5640 of the second link 5610. In this manner, the first link 5510 and the second link 5610 form a wrist assembly 5500 having a first rotation axis A1 (also referred to as a pitch axis), about which the second link 5610 can rotate relative to the first link 5510. A pin 5541 extends through the distal joint portion 5540 and the second link joint portion 5640 to rotatably couple the second link 5610 to the first link 5510. Fig.18As shown, the first link 5510 and the second link 5610 define a longitudinal centerline CL that intersects the pitch axis A1 when the instrument is in an initial (or "straight" configuration).

[0166] The distal second link 5610 has a proximal portion 5611 and a distal portion 5612. As described above, the proximal portion 5611 includes a joint portion 5640 that is rotatably coupled to the joint portion 5540 of the first link 5510. The distal portion 5612 of the second link 5610 includes a connector 5680 that is coupled to the end effector 5460. In this way, the first tool element 5462 and the second tool element 5482 can rotate relative to the second link 5610 about the second rotation axis (also referred to as the yaw axis) A2. The connector 5680 is a pin-type connector and includes a pin 5683 that is supported by (and disposed in) a pin opening 5682. In some embodiments, connector 5680 may include any of the structures and features of a pin-type connector shown and described in U.S. Pat. No. 9,204,923 B2 (filed July 16, 2008), entitled "Medical Instrument Electronically Energized Using Drive Cables," which is incorporated herein by reference in its entirety. Fig.10 As shown, the second rotation axis A2 (also called the yaw axis) is not parallel to the pitch axis A1. Therefore, the instrument 5400 provides up to three degrees of freedom (i.e., pitch motion around the first rotation axis A1, yaw rotation around the second rotation axis A2, and gripping motion around the second rotation axis A2).

[0167] refer to Fig. 20 , 23 25, the second link 5610 includes a first pulley 5660 (which acts as a first sleeve element), and a second pulley 5665 (which acts as a second sleeve element). The first pulley 5660 and the second pulley 5665 are each rotatably coupled to the second link 5610 via a pin 5541. In this way, the first pulley 5660 and the second pulley 5665 can each rotate relative to the second link 5610 around the first rotation axis A1. In other embodiments (not shown), the first pulley 5660 and the second pulley 5665 can be fixedly attached to the second link 5610. The first pulley 5660 includes an outer surface 5661 (see FIG. 5 ) within a grooved channel. Fig.25 ), and the second pulley 5665 includes an outer surface 5666 within a grooved channel (see Fig.25This arrangement allows the first distal center portion 5423 of the first tension element 5420 and the second distal center portion 5433 of the second tension element 5440 to each contact the outer surface 5661 of the first pulley (see Fig.23 and 24 ) - depending on the orientation of wrist assembly 5500. Although not shown, third central portion 5443 of first tension element 5420 and fourth central portion 5453 of second tension element 5440 can similarly contact outer surface 5666 of second pulley 5665. Thus, this arrangement provides a pulley that acts to engage and define portions of the guide path of two different cable portions. Fig.23 As shown, the radius of the first pulley 5660 and the second pulley 5665 is represented by R 滑轮 are determined, and are selected to produce the desired guidance path, as described below.

[0168] like Fig.23 As shown, the second link 5610 defines a first curvilinear guide path 5615 and a second curvilinear guide path 5620. The second link 5610 also includes a first guide surface 5616 and a third guide surface 5617 that are aligned with a portion of the first curvilinear guide path 5615. The second link 5610 also includes a second guide surface 5621 and a fourth guide surface 5622 that are aligned with a portion of the second curvilinear guide path 5620. The first and second curvilinear guide paths 5615, 5620 (and therefore portions of the first tension element 5420 and the second tension element cable 5440 therein) are each offset relative to the longitudinal centerline CL and the first rotation axis A1. In this manner, a torque about the first rotation axis A1 is generated via the application of force by the first tension element 5420 or the second tension element 5440. This can cause the second link 5610 to rotate (i.e., pitch) relative to the first link 5510, as shown in FIG. Fig. 22 As shown by arrow OO in FIG. 5 , a force is applied via first tension member 5420. The offset of the tension member from the longitudinal centerline CL is also based in part on the size of pulley 5660. Fig.23 As shown, when the instrument 5400 is in certain orientations, the outer surface 5661 of the pulley 5660 contacts the first distal central portion 5423 of the first tension element 5420 and the second distal central portion 5433 of the second tension element 5440. Therefore, the radius R of the pulley 5660 is 滑轮 Limit the offset.

[0169] In use, the wrist assembly 5500 can be moved between various orientations. Fig. 22As shown by arrow OO in FIG. , wrist assembly 5500 can be moved between a first (or straight) orientation and a second orientation by rotating second link 5610 relative to first link 5510 about first rotation axis A1. Similarly, second link 5610 can be rotated in the opposite direction about first rotation axis A1 to a third orientation (not shown). When wrist assembly 5500 is in the first orientation, first tension element 5420 is within first tension element path 5615, and second tension element 5440 is within second tension element path 5620. More specifically, first distal central portion 5423 contacts first guide surface 5616 of second link 5610 and surface 5661 of pulley 5660. Second distal central portion 5433 contacts third guide surface 5631 of second link 5610 and surface 5661 of pulley 5660.

[0170] As discussed above in conjunction with wrist assembly 4500 and as Fig.19 , 20 23, the first and second tension elements 5420, 5440 are routed through first and second curvilinear guide paths 5615, 5620 in a low friction parallel alignment relative to the first and second guide paths 5515, 5520 in the first link 5510. Similarly, the second center portion 5443 of the first tension element 5420 and the fourth center portion 5453 of the second tension element 5440 are retained within respective third and fourth curvilinear guide paths (not shown) as described herein with respect to the first and second curvilinear guide paths 5615, 5620. The shape of the third and fourth curvilinear guide paths (not shown) enables the first and second tension elements 5420, 5440 to be routed through the wrist assembly 5500 in a manner that maintains the desired bending geometry, tension of the tension elements, etc. during actuation of the instrument 5400. This also includes routing the first and second tension elements 5420, 5440 in a similar parallel low friction manner.

[0171] refer to Fig. 20 and 23 , the third guide surface 5617 is formed along the distal portion of the first curvilinear guide path 5615 and is curved inwardly relative to the curvilinear guide path 5615, so that the first guide surface 5616 and the third guide surface 5617 are convex relative to each other and relative to the curvilinear guide path 5615. Further, the third guide surface 5617 has an effective radius of curvature R1, which includes the radius of curvature of the third guide surface 5617 plus the thickness of the first tension element 5420 (i.e., the radius of the circular tension element). The third guide surface 5617 is configured to guide the first distal center portion 5423 of the first tension element 5420 through the first guide path 5615 so that when the first guide surface 5616 is in the first curvilinear guide path 5615, the first guide surface 5616 and the third guide surface 5617 are convex relative to each other and relative to the curvilinear guide path 5615. Fig. 20 and23 In the first orientation shown, and when in Fig.21 and 24 In the second orientation shown, in a third orientation (not shown) that is rotated oppositely to the second orientation, and in orientations therebetween, a portion of the first tension element 5420 disposed between the first distal end portion 5422 and the first distal center portion 5423 is aligned parallel to the pulley portion 5467 of the end effector 5460. Thus, by maintaining the parallel alignment of the first tension element between the second link 5620 and the end effector 5460, the third guide surface can reduce frictional contact between the first tension element 5420 and the end effector 5460 including the pulley portion 5467 during movement of the wrist assembly 5500.

[0172] refer to Fig.19 , 20 and 23, when the second connecting rod 5610 is in Fig.19 , 20 and the first orientation shown in 23, and when the second link 5610 is in other orientations (e.g., Fig.21 and 24 5433 of the second tension element 5440. Similarly, throughout a portion of the angular range of motion of the second link 5610 relative to the first link 5510, the second distal central portion 5433 of the second tension element 5440 is in contact with (e.g., wrapped around, such as) the second guide surface 5621 of the second link 5610. Fig.21 , 22 and 24). When in Fig.19 , 20 and the first orientation shown in 23, and when the second link 5610 is along the first link 5510 relative to the first link Fig. 22 When rotated in the direction OO shown, the second guide surface 5621 guides the path of the second tension element 5440 transitioning within the second curved guide path 5620. Further, the second guide surface 5621 is configured to do so while also maintaining the second proximal central portion 5426 and the second proximal end portion 5431 of the second tension element 5440 aligned parallel to the centerline CL3 of the second guide path 5520 of the first link 5510.

[0173] Specifically, the second guide surface 5621 is sized and positioned so that the second proximal portion 5431, the second proximal central portion 5426, or the second proximal portion 5431 and the second proximal central portion 5426 of the second tension element 5440 remain aligned parallel to the centerline CL3 of the second guide path 5520 throughout a portion of the angular range of movement. In this way, the second tension element 5440 can be moved along the second guide path 5520 of the first link. Fig.19 The second guide surface 5621 moves in the direction indicated by the arrow AB without contacting the surface within the second guide path. In this way, frictional contact is reduced with respect to movement of the second tension element 5440 along the direction OO within at least the range of the motion angle. In some embodiments, the second guide surface 5621 has an effective radius of curvature R around the first rotation axis A1. 弯曲 , the effective radius of curvature R 弯曲 equal Fig.16A The distance d1 shown allows the second proximal portion 5431, the second proximal central portion 5426, or the second proximal portion 5431 and the second proximal central portion 5426 of the second tension member to remain parallel to the centerline CL3 within a portion of the range of motion of the second link 5610. Although shown as a single radius of curvature R 弯曲 , but in other embodiments, the second guide surface 5626 can be a curved surface characterized by multiple different radii of curvature.

[0174] When the first tension element 5420 and the second tension element 5440 move in the same direction (e.g., to produce a yaw movement of the end effector 5460), one of the first distal central portion 5423 or the second distal central portion 5433 will move with the rotation of the pulley 5660, and the other of the first distal central portion 5423 or the second distal central portion 5433 will slide against the surface 5661. Generally, the tension element with a larger wrap angle around the pulley 5660 (i.e., the tension element with a larger amount of friction with the surface 5661) will cause the pulley 5660 to rotate, while the tension element with a smaller wrap angle (i.e., the tension element with a smaller amount of friction) will slide against the surface 5661. In this way, the pulley 5660 advantageously reduces friction in the area of ​​maximum friction. This arrangement allows for efficient operation of the end effector 5460 regardless of the pitch orientation of the wrist assembly 5500.

[0175] When the wrist assembly 5500 is in the second orientation ( Fig.21 and 24 ), the first distal central portion 5423 of the first tension element 5420 remains within the first guide path 5615 and contacts the first guide surface 5623. In addition, the first distal central portion 5423 is spaced apart from the pulley 5660. Further, when the wrist assembly 5500 is in the second orientation ( Fig.21 and 24), the second distal central portion 5433 of the second tension element 5440 remains within the second guide path 5620 and contacts (and at least partially wraps around) the surface 5661 of the pulley 5660. Therefore, when axial tension is applied to the second tension element 5440 for pitch movement or movement of the second tool element 5482 for yaw or grip movement, the pulley 5660 rotates with the movement of the second distal central portion 5433. The rotation of the pulley 5660 is based on contact with the second tension element 5440 at the pulley surface 5661, and reduces friction that would otherwise occur when the tension element slides against the surface of the second link 5610 when tension is applied for pitch, yaw, or grip movement.

[0176] In some embodiments, the apparatus 5400 is configured such that one or more pitch tension elements (not shown) are additionally provided to assist other tension elements (e.g., first and second tension elements 5420, 5440) in producing pitch rotations and / or for the primary purpose of producing pitch movement. The pitch tension element can be coupled to the second link 5610 in such a manner that the second link rotates relative to the first link 5510 (i.e., pitch rotations) when the pitch tension element(s) move. In this manner, the wrist assembly 5500 can be, for example, a six-tension element (or six-cable) configuration (two pitch tension elements or pitch tension element portions control pitch rotations and four tension elements or tension element portions control yaw and grip rotations). In other embodiments, any number of pitch tension elements can be provided as appropriate to produce and / or assist in producing pitch movement in the wrist assembly. For example, referring to Figure 26-3 1, shows a diagrammatic example of various portions of an apparatus 6400 including a wrist assembly 6500 having a pitch tension element 6455 for producing pitch rotations, according to an embodiment. Except as described below, apparatus 6400 and wrist assembly 6500 generally include aspects and advantages of the above-described apparatuses (including apparatuses 2400, 3400, 4400, and 5400) and corresponding wrist assemblies.

[0177] In some embodiments, the instrument 6400 or any component thereof is optionally a component of a surgical system that performs a minimally invasive surgical procedure and may include a manipulator unit, a series of kinematic connections, a series of cannulas, etc. The instrument 6400 (and any instrument described herein) can be used in any suitable surgical system (such as the MIRS system 1000 shown and described above). The instrument 6400 includes a wrist assembly 6500, at least one tensioning element 6455, and a tool element 6462. Although only one tensioning element 6455 is shown, one or more additional tensioning elements may be included. As described herein, the instrument 6400 is configured such that movement of the tensioning element 6455 produces movement of the wrist assembly 6500 (such as Fig.26 (as indicated by arrow BB).

[0178] refer to Figure 26-28 , the wrist assembly 6500 includes a proximal first link 6510 and a distal second link 6610. The first link 6510 has a proximal portion 6511 and a distal portion 6512. The proximal portion 6511 is coupled to an instrument shaft (not shown). Figure 26-3 1, but the proximal portion 6511 can be coupled to any suitable instrument shaft, such as the instrument shaft 4410 ( Fig. 9 ). In addition, the proximal portion 6511 of the first link 6510 can be coupled to the instrument shaft via any suitable mechanism (e.g., welding, interference fit, adhesive, etc.). As described below, the distal portion 6512 is rotatably coupled to the second link 6610. In this manner, the first link 6510 and the second link 6610 form a wrist assembly 6500 having a first rotation axis A1 (which serves as a pitch axis; the term pitch is arbitrary) about which the second link can rotate relative to the first link through a range of angles of the wrist assembly.

[0179] The proximal first link 6510 defines a first guide path 6515 within and through the first link, which extends from the proximal portion 6511 of the first link to its distal portion 6512. At least a portion of the first guide path 6515 is parallel to the centerline CL of the shaft, but is offset relative to the centerline of the shaft as further described below. In this way, the centerline CL1 of the first guide path 6515 is offset by a certain distance from the centerline CL of the shaft. In some embodiments, the centerline CL of the shaft is coaxial with the centerline of the first link 6510 and intersects the first rotation axis A1.

[0180] The second link 6610 has a proximal portion 6611 and a distal portion 6612. As described above, the proximal portion 6611 is rotatably coupled to the distal portion 6512 of the first link 6510 to form a wrist-like joint. The rotation axis A1 is located on the centerline CL of the shaft, and in some embodiments, is located on the centerline of the first link 6510, and the centerline of the second link 6610, such as Fig.26 As shown. Figure 26-28 In the first orientation shown, the centerline CL of the first link 6510 is colinear with the centerline of the second link 6610. Therefore, for simplicity and to avoid confusion with the centerline of the path and / or other features defined in the wrist assembly 6500, the centerlines of the first and second links 6510, 6610 and the wrist assembly 6500 are aligned when in the first orientation. Figure 26-28 The first orientation is Figure 26-28Similar to the wrist assembly described above, the distal end portion 6612 of the second link 6610 includes a connector (not shown) that is coupled to the tool element 6462 so that the tool element 6462 can rotate through a certain angle range around a second rotation axis (not shown) relative to the wrist assembly 6500. The connector can be any suitable connector for rotatably coupling the tool element 6462 to the second link 6610 and forming a tool joint.

[0181] refer to Figure 26-28 , the second link 6610 defines a second guide path 6615, a holding pocket 6656, a connection path 6655, and an assembly path 6691. The second guide path 6615 is defined within and through a portion of the second link, and extends from the first guide path 6515 at the proximal portion 6611 of the second link to the connection path 6655. The connection path 6655 is defined within and through a portion of the second link, and extends between the second guide path 6615 and the holding pocket 6656. In some embodiments, the connection path 6655 has a centerline CL2 that intersects the centerline CL1 of the second guide path 6615. The wall 6654 of the second link 6610 surrounds a portion of the connection path 6655. The second link 6610 defines the holding pocket 6656 as an internal cavity formed within the second link 6610, which is coupled to the connection path 6655 at one end of the connection path. In some embodiments, the second link 6610 can define a slot opening 6658 that can provide access to a retention pocket 6656, such as for use during installation of the tension element 6455. As described in further detail below, the retention pocket 6656 is configured to receive and retain a retention element 6459 coupled to the tension element 6455 therein. Further, the retention pocket 6656 is sized to extend beyond the cross-section of the connection path 6655 at its connection with the connection path 6655, such that a wall 6654 surrounding the connection path 6655 forms a barrier that can help retain the retention element 6459 therein. Similar to the connection path 6655, the assembly path 6691 is also defined within and through a portion of the second link 6610, and also extends between the retention pocket 6656 and a portion of the second link proximal to the centerline CL1 of the second guide path 6615. However, as discussed in more detail below in conjunction with tension element 6455 , assembly path 6691 is angled away from connection path 6655 as the path extends outward from retention pocket 6656 .

[0182] The centerline CL2 of the connecting path 6691 is aligned with the centerline CL1 of the second guide path 6615 so that the two paths together form a combined path of the tension element between the first guide path 6515 in the first link 6510 and the retaining pocket 6656 formed in the second link 6610. In this way, the connecting path centerline CL2 intersects the second guide path centerline CL1 at the intersection of the two paths. The intersecting centerlines CL1, CL2 of the aligned paths define a first plane 6605 in the second link 6610. In some embodiments, the first plane 6605 is oriented so that it is transverse relative to the longitudinal axis of the second link 6610. As shown in FIG. Fig. 27 As shown, the first plane 6605 defined in the wrist assembly 6500 corresponds to the line QQ of the cross-sectional view. Fig. 27 The line QQ shown is intercepted Fig.28 The cross-sectional view of provides a view of the wrist assembly 6500 along the first plane 6605 (which includes the centerline CL1 of the second guide path 6615 and the centerline CL2 of the connecting path 6691).

[0183] refer to Fig. 27 and 29 , the assembly path 6691 is not parallel to the second guide path 6615. Instead, as Fig.29 As shown, the assembly path 6691 is non-parallel to (or angled away from) the connection path 6655 as it extends outward from the retention pocket 6656. Further, the centerline CL3 of the assembly path 6691 is configured to be non-parallel to the connection path centerline CL2 of the connection path 6655 within the second plane 6609, which is non-parallel to the first plane 6605. Because both the connection path 6655 and the assembly path 6691 are connected to the retention pocket 6656, when considered from a plane other than the first plane 6605, the centerline CL3 of the assembly path forms an insertion angle 6695 relative to the centerline CL2 of the connection path at the retention pocket 6656.

[0184] In other words, the assembly path 6691 extends outward from the retaining pocket 6656 at an insertion angle 6695, which is oriented away from the connection path 6655 along the first plane 6605 and away from the path of the tension element 6655 within the second link 6610 - including the second guide path 6615 and the connection path 6655, which are aligned to form a path for the tension element between the first link guide path 6515 and the retaining pocket 6656. As discussed further below, the orientation of the assembly path 6691 at the insertion angle 6695 relative to the connection path 6655 and the first plane 6605 allows the tension element 6455 to be more easily installed and routed within the second link 6610 while avoiding damage to the tension element 6455 during installation. Further, the second link defines an open path within the insertion angle 6695 at the interior of the second link located between the connection path 6655 and the assembly path 6691 (see Fig.29 ). In other words, the inner portion of the assembly path 6694 of the connecting path 6655 located between the two paths is open, so that the tension element 6455 can be moved from the assembly path 6691 to the connecting path 6655 when appropriate during installation of the tension element.

[0185] refer to Fig.26 and 29-31, the tension element 6455 has a proximal portion 6456, a distal portion 6458 coupled to a retaining element 6459, and a central portion 6457 disposed between the proximal portion and the distal portion. The proximal portion 6456 is located within a portion of a first guide path 6515 of a first link 6510. Further, the proximal portion 6456 is coupled to an instrument shaft (not shown), which is coupled to a housing of a transmission mechanism (such as the transmission mechanism 4700 described above). The central portion 6457 is between the distal portion 6458 and the proximal portion 6456, and is located within a second guide path 6615 of a second link 6610 and within a portion of a connection path 6655. The retaining element 6459 is coupled to the distal portion 6458 of the tension element 6455, and is configured to fit within a retaining pocket 6656, such that the distal portion 6458 of the tension element extends from the retaining element 6459 and the retaining pocket 6656 to within the connection path 6655. The retaining element 6459 is sized such that it is larger than the distal portion 6458 of the tension element at its connection with the distal portion 6458 of the tension element. Further, the retaining element 6459 is sized to fit within the retaining pocket 6656 such that the wall 6654 surrounding the connection path 6655 forms a barrier to help retain the retaining element 6459 within the retaining pocket 6656 when tension is applied to the tension element along its longitudinal axis to provide pitch movement of the second link 6610 relative to the first link 6510. In other words, the retaining element 6659, the retaining pocket 6656, and the connection path 6655 are configured such that the retaining element cannot move with the connection path 6655.

[0186] Thus, the wrist assembly 6500 is configured to Fig.26 During the pitch movement in the direction BB shown, the tension element 6455 is firmly held in the connecting path 6655 and the second guide path 6615, for example, to move away from the first axis A1. Fig.26 The retention pocket 6656 securely holds the retention element 6459 therein based on beneficial features, such as interference of blocking features such as the wall 6654 surrounding a portion of the connection pathway 6655, and the retention pocket 6656 being sized to be larger than the cross-section of the connection pathway 6691, and the retention element being sized to fit within the retention pocket 6656 and also extend beyond the cross-section of the distal portion 6458.

[0187] Additionally, the wrist assembly 6500 is further configured to improve the ease of installing the tension element 6455 within the wrist assembly 6500, including routing the tension element 6455 through the second link 6610, and installing the retaining element 6459 within the retaining pocket 6656 and other components that may provide the benefit of retaining the tension element within the second link 6610. Further, the wrist assembly 6500 is configured to reduce the likelihood of the tension element 6455 being damaged during installation, such as by avoiding the formation of bends or kinks within the tension element, and reducing the likelihood of cuts and abrasions to the tension element from installation. Such damage to the tension element can cause areas of stress concentration within the tension element, cause corrosion to occur more quickly, adversely affect its structural integrity, alter its performance properties, and otherwise reduce the function, life, and performance of the tension element.

[0188] refer to Figure 29-30 , the instrument 6400 and wrist assembly 6500 are configured to allow the tension element 6455 and the retention element 6459 to be easily installed therein and provide the retention benefits described above, as well as reduce the likelihood of damaging the tension element 6455 during installation. Figure 29-30 As illustrated, wrist assembly 6400 and tension element 6455 are configured such that proximal portion 6456 and central portion 6457 of tension element 6455 can: A) be inserted through assembly path 6691 along assembly path centerline CL3; and B) proximal portion 6456 and central portion 6457 can be rotated until proximal portion 6456 is within first guide path 6515 ( Fig.26 ), and the central portion 6457 is within the second guide path 6615 so that the distal portion 6458 is within the connecting path 6455 when assembled.

[0189] like Fig.31A As shown, the tension element 6455 can be bent at an appropriate bend angle 6495 within its range of flexibility based on its elastic modulus and other tension element properties to assist in the installation of the tension element while avoiding excessive bending or flexing that can damage the tension element. The tension element 6455 can be installed by threading the proximal portion 6456 and the central portion 6457 into the second link through the exposed slot opening 6658 of the retaining bag 6656. The bend angle 6495 can be as shown. Fig.31AThe acute angle shown allows the tension element to flex at a small angle relative to the retaining element 6459 to assist in installation while avoiding kinking, permanent bending, or otherwise damaging the tension element, as may occur at significantly larger bend angles. In some embodiments, the bend angle can be greater than the assembly angle 6695. In some embodiments, the bend angle can be the same as the assembly angle 6695, and in some embodiments, the bend angle can be less than the assembly angle 6695. As described above, the assembly paths 6691 are configured and oriented relative to the retaining bag so that the assembly paths are angled away from the connection paths 6695 - as these paths extend outward from the retaining bag 6656 at the angle 6695. In addition, as Fig.31B and 31C As shown, the centerline CL1 of the assembly path can be oriented away from the connection path 6656 so that the assembly path 6695 is aligned as closely as possible with the slot opening 6658. In this way, a mounting path is formed, through the slot opening 6658 and the retaining pocket 6656, and into and through the angled assembly path 6691, which avoids flexing the tension element 6455 at a large bend angle or passing through a contoured path in order to install the tension element within the wrist assembly 6500.

[0190] When the tension element 6455 has been fully threaded through the assembly path 6595, the retaining element 6459 is Fig.31C When held and installed in the retention bag 6656 as shown, the tension element can be moved from the assembly path 6695 to the connection path 6655 - through the opening spaced between the two paths. Thus, the tension element 6455 can be installed in the wrist assembly 6500 together with the retention element 6459 without significantly bending or flexing the tension element or routing it through a sharp bend that would damage the tension element. In some embodiments (not shown), after the tension element has been partially installed, such as in Fig.31B 6459 can be coupled to the distal portion 6458 of the tension member when in the position shown. Doing so can further prevent excessive bending and flexing of the tension member during installation. However, coupling the retaining element 6459 to the tension member 6455 after the tension member is partially installed can increase other difficulties, such as increasing the likelihood of damaging the wrist assembly 6500 when attaching the retaining element, or reducing the quality or integrity of the connection between the retaining element 6459 and the distal portion 6458 of the tension member.

[0191] The various benefits and advantages discussed herein in conjunction with the various embodiments may be applicable to other example embodiments shown or described herein, and / or combined in yet other embodiments. For example, the various aspects and features relating to wrist assembly 6500 having one or more tension elements configured to provide pitch movement may be combined with other embodiments having tension elements that provide pitch movement in conjunction with movement of the end effector. For example, in some embodiments, one or more tension elements similar to tension element 6455 of wrist assembly 6500 may be added to another instrument, such as instrument 5400 and wrist assembly 5500. In other words, although instrument 5500 is shown as including a four-cable wrist assembly 5500, in other embodiments, wrist assembly 5500 may include two additional pitch cables. In this embodiment, four cable ends (e.g., 5421, 5431, 5441, 5451) can be routed along a friction-reducing guide path similar to that described above and can be manipulated to control grip or yaw rotation of the end effector, and two additional cable ends (see 7456, 7457) can be manipulated to control pitch movement. Additionally, in this embodiment, the pitch cables (or cable ends) can be mounted in a manner similar to that described above with reference to apparatus 6400.

[0192] For example, Figure 32-41 An instrument 7400 having a wrist assembly 7500 is shown according to an embodiment. The instrument generally includes the low friction aspects and components of the above-described instruments (including instruments 2400, 3400, 4400, and 5400) and the corresponding wrist assemblies, except as described below. Specifically, the instrument 7400 includes the low friction aspects and components of the above-described instruments (including instruments 2400, 3400, 4400, and 5400) and the corresponding wrist assemblies. Figure 18-25 ) and such components are not described in detail below. In addition, unlike instrument 5400, instrument 7400 also includes an additional tension element 7455 (having two proximal ends 7456 and 7457), so that wrist assembly 7500 is a six-cable wrist. Additional guide paths, pitch control and movement of wrist assembly 7400, and installation of pitch tension element 7455 are discussed below.

[0193] Figure 32-42 The illustrated apparatus 7400 and wrist assembly 7500 may include any suitable transmission assembly ( Figure 32-42 (not shown), such as the transmission assembly 5700 described above. In addition, the instrument 7400 includes an instrument shaft 5410, a wrist assembly 7500 and an end effector 5460. Fig.32 The apparatus 7400 also includes a first tension member 5420 and a second tension member 5440 that couple the transmission assembly to the wrist assembly 7500, as described above with reference to Figure 18-257400 and the wrist assembly 7500. The apparatus 7400 and the wrist assembly 7500 are described in more detail. However, the apparatus 7400 is configured such that movement of the tension elements 5420, 5440 can produce a yaw rotation of the end effector 5460 about a second axis of rotation A2 ("yaw axis"), and a grip rotation of a tool element of the end effector 5460 about the yaw axis, or any combination of these movements. In addition, the apparatus 7400 and the wrist assembly 7500 include a third tension element 7455, which when moved produces a pitch movement by rotating the second link 7610 relative to the first link 5510 about the first axis A1 through a certain angular rotation range, as further described below. In other embodiments (not shown), the pitch movement can be provided by a combination of movement of the first and second tension elements together with movement of the third pitch tension element.

[0194] refer to Fig.32 , the wrist assembly 7500 includes a proximal first link 5510 and a distal second link 7610. The first link 5510 has a proximal portion 5511 and a distal portion 5512. The proximal portion 5511 is coupled to the distal portion 5412 of the instrument shaft 5410. The distal portion 5512 includes a joint portion 5540, which is rotatably coupled to a mating joint portion 7640 of the second link 5610. In this way, the first link 5510 and the second link 7610 form a wrist assembly 5500 having a first rotation axis A1 (also called a pitch axis), and the second link 7610 can rotate relative to the first link 5510 around the first rotation axis A1. Fig.32 As shown, the first link 5510 and the second link 7610 define a longitudinal centerline that intersects the pitch axis A1 when the instrument is in a first (or "straight") orientation, and the longitudinal centerline is colinear with the shaft centerline CL. Fig.35 As shown, the first link 5510 defines a fifth guide path 7550 and a sixth guide path 7555, which are configured to guide a portion of the third tension member 7455, as further described below. The fifth guide path 7550 and the sixth guide path 7555 are similar to those described above with reference to Fig.11 Guidance path 4550 is shown and described.

[0195] refer to Figure 32-37, the distal second link 7610 has a proximal portion 7611 and a distal portion 7612. As described above, the proximal portion 7611 includes a joint portion 7640, which is rotatably coupled to the joint portion 5540 of the first link 5510. The distal portion 7612 of the second link 7610 includes a connector 7680 coupled to the end effector 5460. In this manner, the first tool element 5462 and the second tool element 5482 can rotate relative to the second link 7610 about a second rotation axis (also referred to as a yaw axis) A2. In addition to the guide paths of the first tension element 5420 and the second tension element 5440 (which are similar to the guide paths 5615, 5620 described above), the second link 7610 further defines a fifth guide path 7650, a sixth guide path 7652, a retaining pocket 7656, a connection path 7655, and an assembly path 7691. The fifth guide path 7650 and the sixth guide path 7652 are each defined within and pass through a portion of the second link, and each extends from a corresponding one of the fifth guide path 7550 and the sixth guide path 7555 of the second link 5510 to the connecting path 7655 .

[0196] like Fig.34 , 41 As shown in Figures 42 and 43, the connecting path 7655 is defined within and passes through a portion of the second link 7610, and extends between the retaining bag 7656 and each of the fifth and sixth guide paths 7650, 7652. In some embodiments, the connecting path 7655 has a centerline CL2 that intersects the centerline CL1 of each of the fifth and sixth guide paths 7650, 7655 ( Fig.36 ). refer to Fig.36 and 37, the wall 7654 of the second link 7610 surrounds a portion of the connection path 7655. The second link 7610 defines a retention pocket 7656 as an internal cavity formed within the second link 7610 that is coupled to a central portion of the connection path 7655. The second link 7610 defines a slot opening 7658 that can provide access to the retention pocket 7656, such as for use during installation of the tension element 7455. As described in further detail below, the retention pocket 7656 is configured to receive and retain a retention element 7459 coupled to the tension element 7455 therein. Further, the retention pocket 7656 is sized to be larger than the cross-section of the connection path 7655 so that the wall 7654 surrounding the connection path 7655 forms a barrier that can help retain the retention element 7459 therein. Similar to the connection path 7655, the assembly path 7691 is also defined within and passes through a portion of the second link 7610, and also extends from the retention pocket 7656 to a portion of the second link proximal to the centerline CL1 of each of the fifth and sixth guide paths 7650, 7652. However, as discussed in more detail below in conjunction with the tension element 7455, the assembly path 7691 is angled away from the connection path 7655 as the paths extend outwardly from the retention pocket 7656.

[0197] The centerline CL2 of the connecting path 7691 is aligned with the centerline CL1 of the fifth and sixth guide paths 7650, 7652. Thus, the connecting path 7691 and the two guide paths 7650, 7652 together form a combined path of the tension element 7455 in the first link 5510 between the fifth and sixth guide paths 7550, 7555, which extends through a retaining pocket 7656 formed in the second link 7610. Thus, at the intersection of the connecting path with the fifth and sixth guide paths 7650, 7652, the connecting path centerline CL2 intersects the centerline CL1. The centerlines CL1 of the paths 7550, 7555 define a first plane 7605 ( Fig.39 In some embodiments, the first plane 7605 is oriented so that it is transverse to the longitudinal axis of the second link 7610. The centerline CL2 of the connection path 7691 can be located within the second plane 7609 within the second link 7610 ( Fig.39 ). The second plane 7609 may be perpendicular to the first plane 7605.

[0198] refer to Fig.41 and 42 - It shows a cross section of the second link 7610 taken along the second plane 7609, the assembly path 7691 is not parallel to the fifth and sixth guide paths 7650, 7652. Instead, as Fig.41As shown, the assembly path 7691 is non-parallel to (or angled away from) the connection path 7655 as it extends outward from the retention pocket 7656. In other words, the centerline CL3 of the assembly path 7691 is configured to be non-parallel to the connection path centerline CL2 of the connection path 7655 within the second plane 7609, which is non-parallel to the first plane 7605. Because both the connection path 7655 and the assembly path 7691 are connected to the retention pocket 7656, when considered from a plane other than the first plane 7605, the centerline CL3 of the assembly path forms an insertion angle 7695 relative to the centerline CL2 of the connection path at the retention pocket 7656.

[0199] In other words, the assembly path 7691 extends outward from the retaining pocket 7656 at an insertion angle 7695, which is oriented away from the connection path 7655 along the first plane 7605 and away from the fifth and sixth guide paths 7650, 7652 of the tension element 7655 within the second link 7610. The insertion angle 7695 can have any suitable value, for example, 5 degrees to 45 degrees. As further discussed below, the orientation of the assembly path 7691 at the insertion angle 7695 relative to the connection path 7655 and the first plane 7605 allows the tension element 7455 to be more easily installed and routed within the second link 7610 while avoiding damage to the tension element 7455 during installation. Further, the second link 7610 defines an open path within the insertion angle 7695 at the interior of the second link between the connection path 7655 and the assembly path 7691 (see Fig.41 ). In other words, the inner portion of the connection path 7655 and the assembly path 7691 located between these two paths is open, so that during installation of the tension element, the tension element 7455 can be moved from the assembly path 7691 to the connection path 7655 when appropriate.

[0200] refer to Fig.34 , 35, 38 and 39, the tension member 7455 has a first proximal portion 7456, a distal portion 7458 coupled to a retaining member 7459, a first central portion 7493 disposed between the first proximal portion and the distal portion, and a second central portion 7494 disposed between the distal portion and the second proximal portion. When installed, the first proximal portion 7456 is located within a portion of the fifth guide path 7550 of the first link 5510. Similarly, the second proximal portion 7457 is located within a portion of the sixth guide path 7555 of the first link 5510. Further, the first and second proximal portions 7456, 7457 are each disposed within an instrument shaft (not shown) that is coupled to a housing of a transmission mechanism (such as the transmission mechanism 5700 described above). The first central portion 7493 is between the first distal portion 7458 and the proximal portion 7458, and is located within the fifth guide path 7650 of the second link 7610 and within a portion of the connecting path 7655. The second central portion 7494 is located between the second distal portion 7457 and the proximal portion 7458 and is positioned within the sixth guide path 7652 of the second link 7610 and within a portion of the connecting path 7655 .

[0201] The retaining element 7459 is connected to the distal portion 7458 of the tension element 7455 and is configured to fit within the retaining pocket 7656 such that the distal portion 7458 of the tension element extends from the retaining element 7459 and the retaining pocket 7656 into the connection path 7655. The retaining element 7459 is sized such that it is larger than the distal portion 7458 of the tension element at its connection to the distal portion 7458 of the tension element. Further, the retaining element 7459 is sized to fit within the retaining pocket 7656 such that the wall 7654 surrounding the connection path 7655 forms a barrier to prevent the tension element from being moved along the longitudinal axis ( Fig.35 When the arrow AB) applies tension to the tension element to provide pitch movement of the second link 7610 relative to the first link 7510, it assists in retaining the retaining element 7459 in the retaining pocket 7656. In other words, the retaining element 7659, the retaining pocket 7656 and the connecting path 7655 are configured so that the retaining element cannot move with the connecting path 7655.

[0202] Thus, the wrist assembly 7500 is configured to securely hold the tension element 7455 within the connection path 7655 and the fifth and sixth guide paths 7650, 7655 during pitch movement, such as for movement away from the first axis A1. Fig.32 and 35The retention pocket 7656 securely holds the retention element 7459 therein based on beneficial features, such as interference of blocking features (such as wall 7654 surrounding a portion of the connection pathway 7655), and the retention pocket 7656 being sized to be larger than the cross-section of the connection pathway 7655, and the retention element being sized to fit within the retention pocket 7656 and also be larger than the cross-section of the distal portion 7458.

[0203] Additionally, wrist assembly 7500 is further configured to improve the ease of installing tension element 7455 within wrist assembly 7500, including routing tension element 7455 through second link 7610, and installing retaining element 7459 within retaining pocket 7656 and other components that may provide benefits in retaining tension element within second link 7610. Further, wrist assembly 7500 is configured to reduce the likelihood of tension element 7455 being damaged during installation, such as by avoiding the formation of bends or kinks in the tension element, and reducing the likelihood of cuts and wear to the tension element from installation.

[0204] refer to Figure 39-42 , the instrument 7400 and wrist assembly 7500 are configured to allow the tension element 7455 and the retention element 7459 to be easily installed therein, along with providing the retention benefits described above, and reducing the likelihood of damaging the tension element 7455 during installation. Figure 39-42 As shown in the example, the wrist assembly 7400 and the tension element 7455 are configured so that the proximal portion 7456 of the tension element 7455 and each of the first and second central portions 7493, 7394 can: A) be inserted through the assembly path 7691 along the assembly path centerline CL2; and B) the first and second proximal portions 7456, 7457 and the first and second central portions 7493, 7394 can be rotated until each of the first and second proximal portions 7456, 7457 is within the corresponding fifth and sixth guide paths 7550, 7555 of the first link 5510 ( Fig.35 ), and the first and second center portions 7493, 7494 are each within the corresponding fifth and sixth guide paths 7650, 7652, so that the distal portion 7458 is within the connecting path 7455 when assembled.

[0205] like Fig.40 and 42As shown, the tension element 7455 can be bent at an appropriate bend angle within its range of flexibility based on its elastic modulus and other tension element properties to assist in the installation of the tension element while avoiding excessive bending or flexing that can damage the tension element. The first and second proximal portions 7456, 7457 and the first and second central portions 7493, 7494 can be screwed into the second link through the exposed slot opening 7658 of the retaining bag 7656 to install the tension element 7455. The bend angle 7495 can be as shown. Fig.42 The acute angle shown allows the tension element to flex at a small angle relative to the retaining element 7459 to assist in installation while avoiding kinking, permanent bending, or otherwise damaging the tension element as may occur at significantly larger bend angles. In some embodiments, the bend angle can be greater than the assembly angle 7695. In some embodiments, the bend angle can be the same as the assembly angle 7695, and in some embodiments, the bend angle can be less than the assembly angle 7695.

[0206] As described above, assembly pathway 7691 is configured and oriented relative to the retention pocket such that the assembly pathway is angled away from connection pathway 7655 as the pathways extend outwardly from retention pocket 7656 at angle 7695. Figure 39-42 As shown, the centerline CL3 of the assembly path can be oriented away from the connection path 7655 so that the assembly path 7691 is aligned as closely as possible with the slot opening 7658. In this way, a mounting path is formed through the slot opening 7658 and the retaining pocket 7656 and into and through the angled assembly path 7691, which avoids the need to flex the tension element 7455 at a large bend angle or through a contoured path in order to install the tension element within the wrist assembly 7500.

[0207] When the tension element 7455 has been screwed through the assembly path 7691 so that the retaining element 7459 is Fig.42 When held and installed in the retaining bag 7656 as shown, the tension element can be moved from the assembly path 7691 to the connection path 765 - through the opening spaced between the two paths. Thus, the tension element 7455 can be installed in the wrist assembly 7500 along with the retaining element 7459 without significantly bending or flexing the tension element or routing it through a sharp bend that would damage the tension element. In some embodiments (not shown), the retaining element can be coupled to the distal portion of the tension element after the tension element has been partially installed. Doing so can further avoid excessive bending and flexing of the tension element during installation.

[0208] Although various embodiments have been described above, it should be understood that they are presented by way of example only and not limitation. Where the above methods and / or schematics indicate certain events and / or flow patterns occurring in a certain order, the order of certain events and / or operations may be changed. Although embodiments have been specifically shown and described, it should be understood that various changes in form and detail may be made.

[0209] For example, any instrument described herein (and the components therein) is optionally a part of a surgical assembly that performs a minimally invasive surgical procedure and may include a manipulator unit, a series of kinematic connections, a series of cannulas, etc. Therefore, any instrument described herein can be used in any suitable surgical system, such as the MIRS system 1000 shown and described above. In addition, any instrument shown and described herein can be used to manipulate target tissue during a surgical procedure. Such target tissue can be cancer cells, tumor cells, injuries, vascular occlusions, thrombosis, stones, uterine fibroids, bone metastases, endometriosis, or any other body tissue. The examples of the target tissues shown are not exhaustive. In addition, the target structure can also be included in an artificial substance (or non-tissue) in or associated with the body, such as, for example, a portion of a stent, an artificial conduit, a fastener in the body, etc.

[0210] For example, any tool element can be constructed of any material (e.g., medical grade stainless steel, nickel alloys, titanium alloys, etc.). Further, any of the connecting rods, tool elements, tension elements, or components described herein can be constructed of multiple pieces that are then connected together. For example, in some embodiments, a connecting rod can be constructed by connecting separately constructed components together. However, in other embodiments, any of the connecting rods, tool elements, tension elements, or components described herein can be constructed as a whole.

[0211] Although the instruments are generally shown as having a second rotation axis A2 that is perpendicular to the first rotation axis A1, in other embodiments, any of the instruments described herein can include a second rotation axis A2 that is offset from the first rotation axis A1 by any suitable angle.

[0212] Although various embodiments have been described as having specific features and / or component combinations, other embodiments are possible having any combination of features and / or components from any of the above-described embodiments. Aspects have been described in the general context of medical devices and more specifically surgical instruments, but aspects of the invention are not necessarily limited to application in medical devices.

[0213] For example, in some embodiments, the instrument can include a tensioning element that is twisted as described above with reference to instrument 5400 and further has one or more links (e.g., a first link or a second link) that include an inner guide surface or an outer guide surface as described above with reference to instrument 3400. Thus, in some embodiments, the instrument can include a wrist assembly that defines a guide surface that can be curved along a longitudinal centerline and can have a linear surface along a cross-section perpendicular to the longitudinal centerline.

Claims

1. A device comprising: An instrument shaft, a first link, a second link, a tool element, and a tension element; The first link is coupled to the instrument shaft and includes a first guide path having a centerline; The second link includes a proximal portion, a distal portion, a second guide path and a curved guide surface, The proximal end portion of the second link is coupled to the first link, The second connecting rod can rotate around the first axis through a certain angle range relative to the first connecting rod. The distal end portion of the second link is coupled to the tool element, the tool element being rotatable relative to the second link about a second axis, the second guide path is located between the tool element and the first guide path, and The curvilinear guide surface defines a portion of the second guide path; and The tension element comprises a first tension element portion, a second tension element portion and a third tension element portion between the first tension element portion and the second tension element portion, the first tension element portion being within the first guide path and parallel to the centerline of the first guide path, The second tension element portion is coupled to the tool element, and The third tension element portion contacts the curved guide surface through a portion of the angular range of the second link.

2. A device comprising: an instrument shaft, a tool element, a first link coupled to the instrument shaft, a second link, and a tension element; The instrument shaft has an axial centerline; the first link including a first guide path having a centerline, the centerline of the first guide path being offset from the axial centerline of the instrument shaft by an offset distance; The second link includes a proximal portion, a distal portion, a second guide path and a curved guide surface, The proximal portion is coupled to the first link, The second connecting rod can rotate around the first axis through a certain angle range relative to the first connecting rod. The distal end portion of the second link is coupled to the tool element, the tool element being rotatable relative to the second link about a second axis, the second guide path is located between the tool element and the first guide path, The curvilinear guide surface defines a portion of the second guide path, the curvilinear guide surface being characterized by a radius about the first axis, and the radius being equal to the offset distance; and The tension element comprises a first tension element portion, a second tension element portion and a third tension element portion between the first tension element portion and the second tension element portion, the first tension element being partially within the first guide path, The second tension element portion is coupled to the tool element, and The third tension element portion contacts the curved guide surface throughout at least a portion of the angular range of the second link.

3. A device comprising: an instrument shaft, a tool element, a first link coupled to the instrument shaft, a second link, and a tension element; The instrument shaft has an axial centerline; the first link including a first guide path having a centerline offset a first distance from the axial centerline of the instrument shaft; The second link includes a proximal portion, a distal portion, a second guide path and a curved guide surface, The proximal portion is coupled to the first link, The second connecting rod can rotate around the first axis through a certain angle range relative to the first connecting rod. The distal end portion of the second link is coupled to the tool element, the tool element being rotatable relative to the second link about a second axis, the second guide path is located between the tool element and the first guide path, the curvilinear guide surface defining a first portion of the second guide path, the curvilinear guide surface being characterized by a radius of curvature, the center of the radius of curvature being offset a second distance from the axial centerline of the instrument shaft, and the second distance being equal to the sum of the radius of curvature and the first distance; and The tension element comprises a first tension element portion, a second tension element portion and a third tension element portion located between the first tension element portion and the second tension element portion, the first tension element being partially within the first guide path, The second tension element portion is coupled to the tool element, and The third tension element portion contacts the curved guide surface throughout at least a portion of the angular range of the second link.

4. A device comprising: An instrument shaft, a first link, a second link, a tool element, and a tension element; The first link is coupled to the instrument shaft and includes a first guide path having a centerline; The second link includes a proximal portion, a distal portion, and a second guide path, The proximal end portion of the second link is coupled to the first link, The second connecting rod can rotate around the first axis through a certain angle range relative to the first connecting rod. The distal end portion of the second link is coupled to the tool element, the tool element being rotatable relative to the second link about a second axis, the second guide path being located between the tool element and the first guide path; as well as The tension element comprises a first tension element portion, a second tension element portion and a third tension element portion, the first tension element portion being within the first guide path and parallel to the centerline of the first guide path, the second tension element portion being coupled to the tool element, In the second link, the third tension element portion is between the first tension element portion and the second tension element portion, and the third tension element portion remains parallel to the center line of the first guide path through the certain angle range of the second guide path through the second link.

5. A device comprising: An instrument shaft, a first link, a second link, a tool element, and a tension element; The first link is coupled to the instrument shaft and includes a first guide path having a centerline; The second link includes a proximal portion, a distal portion, a second guide path, an inner guide surface, and an outer guide surface, The proximal end portion of the second link is coupled to the first link, The second connecting rod can rotate around the first axis through a certain angle range relative to the first connecting rod. The distal end portion of the second link is coupled to the tool element, the tool element being rotatable relative to the second link about a second axis, the second guide path is located between the tool element and the first guide path, and A portion of the second guide path is defined by the inner guide surface and the outer guide surface; and The tension element comprises a first tension element portion, a second tension element portion and a third tension element portion between the first tension element portion and the second tension element portion, the first tension element portion being within the first guide path and parallel to the centerline of the first guide path, The second tension element portion is coupled to the tool element, and The third tension element portion contacts the inner guide surface throughout a first portion of the angular range of the second link, and contacts the outer guide surface throughout a second portion of the angular range of the second link.

6. A device comprising: An instrument shaft, a first link, a second link, a tool element, and a tension element; The first link is coupled to the instrument shaft having an axial centerline and includes a first guide path having a centerline, The centerline of the first guide path is offset from the axial centerline of the instrument shaft by an offset distance; the second link includes a proximal portion, a distal portion, a second guide path and an inner guide surface, The proximal end portion of the second link is coupled to the first link, The second connecting rod can rotate around the first axis through a certain angle range relative to the first connecting rod. The distal end portion of the second link is coupled to the tool element, the tool element being rotatable relative to the second link about a second axis, the second guide path is located between the tool element and the first guide path, The inner guide surface defines a portion of the second guide path, and The outer radius of the inner guide surface is equal to the offset distance; and The tension element comprises a first tension element portion, a second tension element portion and a third tension element portion between the first tension element portion and the second tension element portion, the first tension element portion being within the first guide path and parallel to the centerline of the first guide path, The second tension element portion is coupled to the tool element, and The third tension element portion contacts the inner guide surface through a portion of the angular range of the second link.

7. A device comprising: An instrument shaft, a first link, a second link, a tool element, and a tension element; The first link is coupled to the instrument shaft having an axial centerline and includes a first guide path having a centerline, The centerline of the first guide path is offset from the axial centerline of the instrument shaft by an offset distance; the second link includes a proximal portion, a distal portion, a second guide path and an outer guide surface, The proximal end portion of the second link is coupled to the first link, The second connecting rod can rotate around the first axis through a certain angle range relative to the first connecting rod. The distal end portion of the second link is coupled to the tool element, the tool element being rotatable relative to the second link about a second axis, the second guide path is located between the tool element and the first guide path, the outer guide surface defines a portion of the second guide path; and The tension element comprises a first tension element portion, a second tension element portion, a third tension element portion and a fourth tension element portion, the first tension element portion being within the first guide path and parallel to the centerline of the first guide path, the second tension element portion being coupled to the tool element, The third tension element portion is between the first tension element portion and the second tension element portion and in the second link, and during a portion of the certain angular range of the second link, the third tension element portion is maintained parallel to the center line of the first guide path by the curvature radius of the outer guide surface.

8. A method of assembling an apparatus comprising a tension element and a link, the tension element comprising a first tension element portion, a second tension element portion, and a retaining element coupled to the second tension element portion, the link defining an assembly path, a guide path, and a retaining pocket, the method comprising: positioning the tensile member in a first position in which the first tensile member is partially within the assembly path; and The tensile element is rotated about the rotational axis to a second position to move the first tensile element portion from the assembly path into the guide path and position the retaining element within the retaining pocket.

9. A method of assembling an apparatus, the apparatus comprising a tension element and a connecting rod, the tension element comprising a first end portion, a second end portion, and a third portion coupled between the first end portion and the second end portion, the connecting rod defining an assembly path, a guide path, and a connection path, the method comprising: positioning the third portion of the tension element on a first side of the link; positioning the first and second end portions of the tensile element on a second side of the link within the assembly path while positioning the third portion of the tensile element on the first side of the link, the second side of the link being opposite the first side of the link; and The tension element is rotated about a rotation axis to move the first and second end portions of the tension element from the assembly path into the guide path and to position the third portion within the connection path.

10. A device comprising: an instrument shaft, a link operably coupled to the instrument shaft, and a tensioning element; The connecting rod includes a guide path having a centerline, a connection path having a centerline, an assembly path having a centerline, a retaining pocket and a wall, The connecting path extends through a portion of the connecting rod between the guide path and the holding bag, The wall of the connecting rod surrounds a portion of the connecting path, the centerline of the connecting path and the centerline of the guiding path define a first plane such that the connecting path and the guiding path are coplanar within the connecting rod, The assembly path extends through the portion of the connecting rod into the holding pocket, and The centerline of the assembly path is non-parallel to the centerline of the connection path in a second plane that is non-parallel to the first plane; and The tension element comprises a first tension element portion, a second tension element portion and a retaining element coupled to the second tension element portion, wherein: the assembly path being configured to receive the first tensile member portion along the centerline of the assembly path in a first condition, wherein the first tensile member portion is in a first position in the first condition, The tensile element is configured to rotate to transition the first tensile element portion from the assembly path into the guide path, the retaining element is retained within the retaining pocket in a second condition in which the first tension element portion is in a second position within the guide path such that movement of the tension element relative to the connecting rod is restricted, and Movement of the first tension element portion within the guide path causes the link to rotate relative to the instrument axis.

11. A wrist assembly, comprising: a first link, a second link rotatably coupled to the first link, and a tension member; The first link defines a first guide path; The second link defines a second guide path having a centerline, a connection path having a centerline, an assembly path having a centerline, a retaining pocket, a first wall, and a second wall, The second link is rotatable relative to the first link about a first axis, the connecting path extends through a portion of the second link between the second guide path and the holding bag, the first wall comprising an elongated slot opening into the retaining pocket, the second wall of the second link defining a distal boundary of the retention pocket, The centerline of the connecting path and the centerline of the second guide path define a first plane such that the connecting path and the second guide path are coplanar within the second link, The assembly path extends through the portion of the second link into the holding pocket, and The centerline of the assembly path is non-parallel to the centerline of the connection path in a second plane that is non-parallel to the first plane; and The tension element comprises a first tension element portion, a second tension element portion and a retaining element coupled to the second tension element portion, wherein: the assembly path being configured to receive the first tensile member portion along the centerline of the assembly path via the elongated slot in a first condition, wherein the first tensile member portion is in a first position in the first condition, The tensile element is configured to rotate to transition the first tensile element portion from the assembly path into the second guide path, the retaining element is retained within the retaining pocket in a second condition in which the first tension element portion is in a second position within the second guide path such that movement of the tension element relative to the second link is limited, and Movement of the first tension element portion within the second guide path causes the second link to rotate relative to the first link about the first axis.

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