Snake bone joint, flexible joint assembly, surgical operation arm and surgical robot

Abstract

The utility model discloses a snake bone joint, a flexible joint assembly, a surgical operation arm and a surgical robot. The problem that uncertain dislocation sliding occurs between snake bone components when the snake bone joint is bent can be solved. Each snake bone joint comprises two snake bone components, a supporting structure and at least two traction soft ropes, each snake bone component can rotate based on a respective pivot, the supporting structure is arranged between the two snake bone components, the two pivots in the same snake bone joint are parallel, and the distance between the two pivots is constant; the traction soft ropes are connected between the two snake bone components in a pre-tightening state, and the projections of at least one pair of traction soft ropes in the extension direction of the pivot are in a crossed symmetrical state; each snake bone component comprises a limiting cambered surface used for tensioning the corresponding traction soft rope, the axis of each limiting cambered surface is parallel to or coincides with the pivot, the radiuses of the limiting cambered surfaces tightly attached to the same pair of traction soft ropes are equal, and the starting ends of the limiting cambered surfaces are fixed to the ends of the traction soft ropes. Therefore, the snake bone joint has the advantage of improving the bending precision and load deformation resistance of the snake bone joint.

Description

Technical Field

[0001] This application relates to the technical field of medical devices, and more specifically, to a snake-bone joint, a flexible joint assembly, a surgical arm, and a surgical robot. Background Technology

[0002] Snake-bone joints are self-bending components widely used in the medical device field. Operators can control the insertion and orientation of tools at the distal end of the surgical arm into the body by bending at least one segment of the snake-bone joint, thereby enabling observation and surgical procedures at designated locations. Snake-bone joints typically consist of multiple snake-bone components, which can rotate in coordination to achieve the self-bending function of the joint.

[0003] In related technologies, although the snake-bone joint can achieve bending at a specified angle by pulling back and releasing the drive cables threaded between the various snake-bone components, the relative rotational state between the snake-bone components is uncertain. During bending, it is difficult to ensure consistent cable retraction or maintain a balance of the lever arms of the drive cables on both sides of the snake-bone joint. This makes the drive cables prone to deformation or even damage, thus affecting the service life of the snake-bone joint and the surgical arm. Furthermore, the uncertain relative rotational state between the snake-bone components prevents the snake-bone joint from having a unique shape at a specified bending angle. When any snake-bone component is subjected to external force, the snake-bone joint is highly susceptible to deformation, introducing uncertainties and risks to the surgical procedure and reducing the reliability of the snake-bone joint and surgical arm when used in surgical operations. Utility Model Content

[0004] The purpose of this application is to provide a snake joint, a flexible joint component, a surgical arm, and a surgical robot, which can alleviate the problem of uncertain misalignment and slippage between snake components when the snake joint is bent, and improve the bending accuracy and load deformation resistance of the snake joint.

[0005] The embodiments of this application are implemented as follows:

[0006] In a first aspect, embodiments of this application provide a snake-bone joint, which includes two snake-bone components and at least one support structure. Each snake-bone component is rotatable based on its own pivot. The support structure is disposed between the two snake-bone components. The two pivots in the same snake-bone joint are parallel and the distance between them is constant. The snake-bone joint also includes at least two traction ropes. The traction ropes are connected between the two snake-bone components in a pre-tensioned state. The projections of at least one pair of traction ropes in the direction of pivot extension are cross-symmetrical. Each snake-bone component includes a limiting arc surface for tensioning the traction rope. The axis of the limiting arc surface is parallel to or coincides with the pivot. The radii of the limiting arc surfaces that the same pair of traction ropes are in close contact with are equal. The starting end of the limiting arc surface is fixed to the end of the traction rope.

[0007] In the above technical solution, the two snake-bone components are rotatably connected by a support structure, which can keep the pivot distance between the two snake-bone components in the same snake-bone joint constant. With the pivots parallel to each other and the distance constant, the snake-bone joint is equipped with at least a pair of traction ropes arranged in a cross-symmetrical manner. Each traction rope is connected between the two snake-bone components in a pre-tensioned state. Each traction rope is tensioned by a limiting arc surface with equal radius and axis parallel or coincident with the pivot and fixed at the end. When the two snake-bone components rotate relative to each other based on a specified bending angle of the snake-bone joint, the snake-bone joint can apply bidirectional equal constraint force to the two snake-bone components through the traction ropes in the pre-tensioned state. This allows the snake-bone joint to achieve a symmetrical motion configuration during bending and has a unique shape at the specified bending angle, reducing the probability of misalignment and slippage between the snake-bone components, thereby improving the bending accuracy and load deformation resistance of the snake-bone joint. In addition, the support structure can share the pressure load, which is generated by the interaction between the snake-bone components due to the tightening of the drive cables. This can reduce the wear of the snake-bone components and extend the service life of the snake-bone components and snake-bone joints.

[0008] In some embodiments, in the snake-bone joint, the distance between the two pivots is the center distance of the snake-bone joint; the radius of the limiting arc surface does not exceed half of the center distance. In the above technical solution, the radius of the limiting arc surface does not exceed half of the center distance, which helps to reduce the processing difficulty of the snake-bone components and the assembly difficulty of the snake-bone joint, and improves the smoothness of the snake-bone joint bending.

[0009] In some embodiments, when the radius of the limiting arc surface is equal to half the center distance, a groove for accommodating the traction rope is provided on the limiting arc surface. In the above technical solution, when the radius of the limiting arc surface is equal to half the center distance, the limiting arc surfaces of the two snake-bone components abut and roll in contact. Placing the traction rope in the groove can balance the constraint of the traction rope on the snake-bone components with the simplification of the overall structure, while also reducing the wear of the traction rope and extending the service life of the snake-bone joint.

[0010] In some embodiments, on the same serpentine component, the limiting arc surface includes a first arc surface and a second arc surface. The first arc surface is used to tension one traction rope, and the second arc surface is used to tension the other traction rope. The larger the radius of the first arc surface and the second arc surface, the larger the circumferential extension angle of the first arc surface and the second arc surface. In the above technical solution, a pair of traction ropes can be tensioned by different limiting arc surfaces. When the maximum bendable angle of the serpentine joint is determined, the minimum circumferential extension angle of each limiting arc surface is related to the radius of the limiting arc surface, so that the traction ropes always exert a constraint force on the two serpentine components through the tension of the limiting arc surfaces, thereby reducing the probability of misalignment deformation and improving the bending accuracy and load deformation resistance of the serpentine joint.

[0011] In some embodiments, on the same snake-bone component, the first arc surface and the second arc surface are connected or partially overlapped to form a semi-circular arc surface. In the above technical solution, the two limiting arc surfaces used to tension the first traction rope and the second traction rope are connected or partially overlapped to form a semi-circular arc surface, making the structure of the snake-bone component simpler and more compact, and more conducive to processing and assembly.

[0012] In some embodiments, in the snake-bone joint, each end of the pivot is provided with a pair of traction ropes arranged in a cross-symmetrical pattern. In the above technical solution, each side of the snake-bone joint along the pivot extension direction is restricted to the misalignment and deformation of the snake-bone component by at least a pair of traction ropes arranged in a pre-tensioned state, which can improve the stability and reliability of the snake-bone joint bending and can bear external loads more evenly.

[0013] In some embodiments, the traction rope includes a first traction rope and a second traction rope, the projections of which are symmetrically arranged in the direction of pivot extension. In the serpentine joint, the first traction rope is located at one end of the pivot, and the second traction rope is located at the other end of the pivot. In the above technical solution, the first and second traction ropes, with their projections symmetrically arranged, are respectively located on both sides of the serpentine joint, which can improve the stability and reliability of the serpentine joint bending and can more evenly bear external loads.

[0014] In some embodiments, the traction rope includes at least one flexible traction wire, the cross-sectional shape of which is circular or rectangular. In the above technical solutions, the circular cross-section of the flexible traction wire results in more uniform stress distribution and reduces wear, while the rectangular cross-section of the flexible traction wire provides higher strength and torsional resistance, and facilitates the directional application of constraint forces. Combining multiple flexible traction wires increases structural strength and promotes uniform load distribution.

[0015] In some embodiments, the snake-bone component includes two first end faces facing away from each other, and the pivots corresponding to the limiting arc surfaces respectively disposed on the two first end faces are perpendicular. In the above technical solution, one snake-bone component can be used simultaneously in the assembly of two snake-bone joints with mutually perpendicular bending directions, which improves the compactness and simplicity of the overall structure of the snake-bone joint, and can save on the processing materials of the snake-bone component.

[0016] In some embodiments, in a snake-bone joint, the surfaces of two snake-bone components facing each other and adjacent to each other are first end faces; each support structure includes two rolling contact arc-shaped top surfaces with equal radii, one arc-shaped top surface being disposed on the first end face of one snake-bone component and the other arc-shaped top surface being disposed on the first end face of another snake-bone component, the axis of the arc-shaped top surfaces coinciding with the pivot. In the above technical solution, the arrangement of the arc-shaped top surfaces can reduce the wear of the snake-bone components, and the rolling contact between the arc-shaped top surfaces can improve the smoothness of the bending of the snake-bone joint and the stability of the structure, improve the load-bearing capacity of the snake-bone components, and reduce the processing difficulty of the snake-bone components.

[0017] In some embodiments, the radius of the top surface of the arc is equal to half the center distance of the snake-bone joint; when the radius of the limiting arc surface is equal to half the center distance, the top surface of the arc coincides with the limiting arc surface. In the above technical solution, the coincidence of the top surface of the arc and the limiting arc surface can improve the simplicity of the snake-bone component structure and reduce the processing difficulty of the snake-bone component.

[0018] In some embodiments, in the same support structure, at least one side of the top surface of an arc is provided with a retaining edge, and the limiting direction corresponding to the retaining edge is the same as the pivot extension direction. In the above technical solution, the retaining edge provided on at least one side of the top surface of the arc can reduce the probability of misalignment between snake bone components along the pivot during the bending process of the snake bone joint, and improve the bending accuracy of the snake bone joint.

[0019] In some embodiments, the support structure includes at least one connecting pin, each connecting pin comprising two connecting shafts and a connecting rod, the connecting rod being vertically connected between two parallel connecting shafts; in the snake-bone joint, the connecting shafts correspond one-to-one with the snake-bone components and are rotatably connected, the axis of the connecting shafts coinciding with the pivot. In the above technical solution, the snake-bone joint fixes the center distance between the two snake-bone components through the connecting pins, making it difficult for the two snake-bone components to approach or move away from each other during the cooperative rotation process, thereby improving the bending accuracy and bending reliability of the snake-bone joint.

[0020] In some embodiments, each snake-bone component includes multiple sets of lanyard holes symmetrically arranged on both sides of the pivot. These lanyard holes are used to accommodate drive cables or constraint cables. In the above technical solution, the symmetrical arrangement of multiple sets of lanyard holes makes the overall structure of the snake-bone joint and flexible joint assembly more compact, and also reduces the pulling and interference on the constraint cables or drive cables during rotation of the snake-bone components. Furthermore, the symmetrical arrangement of the lanyard holes ensures that the connection positions of the drive cables on both sides of the snake-bone joint to each snake-bone component are symmetrical and equidistant from the pivot. When the snake-bone joint can achieve a symmetrical motion configuration, the symmetrical arrangement of the lanyard holes allows the drive cables on both sides of the snake-bone joint to achieve consistent extension and retraction with balanced lever arms, thereby extending the service life of the drive cables.

[0021] In some embodiments, in the snake-bone joint, the surfaces of two snake-bone components facing each other and adjacent to each other are first end faces; on either first end face, along a direction perpendicular to the pivot, both ends of the first end face are provided with limiting inclined surfaces that are inclined relative to the first end face and have equal inclination angles. In the above technical solution, the setting of the limiting inclined surfaces can limit the maximum rotation angle of the snake-bone components toward one side, that is, limit the maximum bending angle of the snake-bone joint toward one side, reduce edge collisions and wear between snake-bone components, and extend the service life of the snake-bone components.

[0022] Secondly, embodiments of this application provide a flexible joint assembly. This flexible joint assembly includes at least one snake-bone joint as described in any embodiment of the first aspect of this application and at least two drive cables. Each drive cable extends and passes through each snake-bone joint, and one end of each drive cable is fixed to the most distal snake-bone component of the flexible joint assembly. In the above technical solution, the flexible joint assembly drives the snake-bone joint to bend by extending and retracting the drive cables, thereby achieving its own deflection. The flexible joint assembly has the same technical effect as the aforementioned snake-bone joint.

[0023] In some embodiments, the flexible joint assembly includes at least two serpentine joints with the same pivot extension direction. The flexible joint assembly also includes at least two constraint cables, each extending and passing through a serpentine joint. The connection positions of the constraint cables on the serpentine members are pivotally symmetrical. Between the two serpentine joints with the same pivot extension direction and the closest positions, the connection position of each constraint cable with the nearest serpentine joint is a first connection position, and the connection position of each constraint cable with the farthest serpentine joint is a second connection position. The first connection position is shifted by 180° relative to the second connection position based on the central axis of the flexible joint assembly. In the above technical solution, the 180° shift of the constraint cables ensures that the two serpentine joints with the closest positions and the same bendable direction have a fixed bending angle when the flexible joint assembly deflects as a whole. That is, the flexible joint assembly has a unique shape at a specified deflection angle. This embodiment improves the load-bearing deformation resistance of the flexible joint assembly.

[0024] Thirdly, embodiments of this application provide a surgical operating arm, which includes at least one flexible joint component provided in any embodiment of the second aspect of this application. In the above technical solutions, the surgical operating arm has the same technical effects as the aforementioned flexible joint component.

[0025] Fourthly, embodiments of this application provide a surgical robot, which includes at least one surgical operating arm provided in any embodiment of the third aspect of this application. In the above technical solutions, the surgical robot has the same technical effects as the aforementioned surgical operating arm.

[0026] The advantages of this application compared to the prior art are:

[0027] This application addresses the problem of misalignment and slippage between snake-bone components during bending of a snake-bone joint. When two snake-bone components rotate relative to each other, traction ropes arranged in a symmetrical, cross-shaped configuration under pre-tension apply the same constraint force to both components. This ensures a symmetrical motion configuration of the snake-bone joint during bending, with a unique shape at a specified bending angle, reducing the probability of misalignment and slippage between the components and ultimately improving the bending accuracy and load-bearing deformation resistance of the snake-bone joint. Furthermore, the traction ropes include at least one flexible traction wire with a circular or rectangular cross-section, which facilitates uniform force distribution, reduces wear, or provides higher strength and directional constraint force. Combining multiple flexible traction wires increases structural strength and promotes uniform load distribution. Placing the traction rope in the embedded groove balances the constraint of the traction rope on the snake-bone component with the simplification of the overall structure, and also reduces the wear of the traction rope. Each side of the snake-bone joint is equipped with a traction rope, which improves the stability and reliability of the snake-bone joint bending and distributes the external load more evenly. Multiple sets of rope holes are based on pivot symmetry, which makes the drive cable retraction and extension consistent and the lever arm balanced during the bending of the snake-bone joint. The constraint cables between the two snake-bone joints with the same pivot extension direction and the closest position are connected by a 180-degree shift, so that the flexible joint component usually has a unique shape at a specified deflection angle, which improves the load deformation resistance of the flexible joint component. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the overall structure of the surgical robot shown in some embodiments of this application;

[0030] Figure 2 This is a schematic diagram of the overall structure of the surgical arm shown in some embodiments of this application;

[0031] Figure 3 This is a schematic diagram of the overall structure of a flexible joint component shown in some embodiments of this application;

[0032] Figure 4 This is a schematic diagram of the overall structure of the second flexible joint assembly shown in some embodiments of this application;

[0033] Figure 5This is a schematic diagram of the constraint cable layout of the second flexible joint assembly shown in some embodiments of this application;

[0034] Figure 6 This is a schematic diagram of the overall structure of the snake-bone joint shown in some embodiments of this application;

[0035] Figure 7 This is a schematic diagram of the overall structure of a snake-bone joint, as shown in another embodiment of this application;

[0036] Figure 8 This is an exploded schematic diagram of a snake-bone joint shown in some embodiments of this application;

[0037] Figure 9 This is an exploded schematic diagram of a snake-like joint shown in other embodiments of this application;

[0038] Figure 10 This is a front view schematic diagram of a snake-bone joint shown in some embodiments of this application;

[0039] Figure 11 This is a schematic cross-sectional view of a traction rope shown in some embodiments of this application;

[0040] Figure 12 This is a schematic diagram illustrating the geometric principle of the symmetrical motion configuration of the snake-bone joint shown in some embodiments of this application;

[0041] Figure 13 This is a schematic diagram illustrating the geometric principle of the symmetrical motion configuration of the snake-bone joint, as shown in some other embodiments of this application.

[0042] Figure 14 This is a schematic diagram illustrating the geometric principle of a partial structure of a snake-bone joint, as shown in some embodiments of this application.

[0043] Icons: 1-Surgical robot; 2-Surgical arm; 3-Flexible joint component; 4-Snake joint; 5-Snake component; 21-Tool head; 22-Instrument box; 23-Straight instrument tube; 30-Flexible joint assembly; 31-First flexible joint assembly; 32-Second flexible joint assembly; 33-Drive cable; 34-Constraint cable; 340-Connection position; 341-First connection position; 342-Second connection position; 35-Connecting straight tube; 40-Dual snake joint; 401-First snake joint; 402-Second snake joint; 403-Third snake joint; 404-Fourth snake joint; 41-Support Support structure; 42-Arc-top unit; 420-Arc-top surface; 421-Side guard; 43-Connecting pin assembly; 431-Connecting pin; 4311-Connecting pin shaft; 4312-Connecting rod; 432-Anti-detachment component; 50-Pivot; 500-Reference circle; 51-Rotating base; 510-First end face; 511-Rope hole; 512-Limiting inclined surface; 52-Traction rope; 520-Flexible traction wire; 521-First traction rope; 522-Second traction rope; 53-Limiting arc surface; 530-Starting end of limiting arc surface; 531-First arc surface; 532-Second arc surface; 533-Embedded groove. Detailed Implementation

[0044] The terms “first,” “second,” “third,” etc., are used only for distinguishing descriptions and do not indicate a sequence number, nor should they be interpreted as indicating or implying relative importance.

[0045] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0046] In the description of this application, it should be noted that the terms "inner", "outer", "left", "right", "upper", "lower", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0047] In the description of this application, unless otherwise expressly specified and limited, the terms “set up,” “install,” “connect,” and “link” shall be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection; as a mechanical connection or an electrical connection; as a direct connection or an indirect connection through an intermediate medium; or as a connection within two components.

[0048] The technical solution of this application will now be described in detail with reference to the accompanying drawings.

[0049] Surgical robots, as an important research technology in the field of medical devices, are widely used in surgical procedures, assisting surgeons in performing various types of minimally invasive and non-invasive surgeries. Among them, surgical robots with flexible joint components or snake-bone joints are specially designed robots that can operate in confined spaces and perform complex bending or rotational movements inside the human body. Compared with traditional rigid surgical instruments, this type of surgical robot has many advantages. Using this type of surgical robot to perform surgery can not only improve the precision of surgical operations, but also reduce damage to surrounding tissues at the surgical site, shorten recovery time, and reduce the risk of complications.

[0050] Snake-bone joints are biomimetic joint structures designed to create instruments that can bend and twist to reach areas inside the body that are difficult to access with ordinary tools. For example, in endoscopic surgery, surgical instruments with snake-bone joints can help surgeons more accurately locate lesions and perform more delicate procedures. While snake-bone joints can bend by pulling and releasing drive cables threaded between the individual snake-bone components, the relative rotational state between these components is uncertain. The snake-bone joint cannot maintain a unique shape at a specified bending angle, and it is easily deformed by external forces, affecting the reliability and safety of surgical procedures.

[0051] Based on the above considerations, this application provides a snake-bone joint, including two snake-bone components and at least one pair of traction ropes maintained in a pre-tensioned state. The projections of the at least one pair of traction ropes in the pivot extension direction are cross-symmetrical, and each traction rope is tensioned on the limiting arc surface of the two snake-bone components. Thus, the snake-bone components are always subjected to bidirectional constraint forces applied by the two traction ropes during rotation and at rest. The snake-bone joint can achieve a symmetrical motion configuration during bending and has a unique shape at a specified bending angle. This application reduces the probability of uncertain misalignment and slippage between the snake-bone components, improving the bending accuracy and load deformation resistance of the snake-bone joint.

[0052] Please see Figure 1 , Figure 1 This is a schematic diagram of the overall structure of the surgical robot 1 shown in some embodiments of this application. For example... Figure 1As shown, the surgical robot 1 may include at least one surgical arm 2. The surgical arm 2 is used to perform actions required for surgical procedures via tool heads 21. Tool heads 21 refer to the direct execution instruments on the surgical robot 1 that participate in surgical procedures. Different tool heads 21 may have different functions, and may include needle forceps, electric hooks, electric shovels, bipolar window forceps, bipolar Maryland forceps, cardill forceps, intestinal forceps, tweezers, graspers, needles, scalpels, scissors, cauterizers, endoscopes, and anastomosing devices, etc. The tool head 21 can be mounted on the distal end of the surgical arm 2 via a docking port, drive cable 33, or other structures. The distal end of the surgical arm 2 refers to the end of the surgical arm 2 used to insert into the human body and perform surgical procedures.

[0053] Please see Figure 2 , Figure 2 This is a schematic diagram of the overall structure of the surgical arm 2 shown in some embodiments of this application. For example... Figure 2 As shown, the surgical arm 2 may include an instrument box 22, a flexible joint component 3, an instrument tube 23, and a tool head 21. The flexible joint component 3 may include at least one flexible joint assembly 30. One end of the flexible joint component 3 can be connected to the instrument box 22 via the instrument tube 23, and the other end of the flexible joint component 3 can be connected to the tool head 21.

[0054] In this embodiment, the flexible joint component 3 or flexible joint assembly 30 refers to a structure composed of at least one snake-bone joint 4, which can achieve directional deflection function by tightening or loosening the drive cable 33; the instrument box 22 refers to a device that can drive the tool head 21, flexible joint assembly 30 or instrument straight tube 23 to move through a transmission structure and a power source (such as a servo motor or other components).

[0055] In some embodiments, the instrument tube 23 can be a hollow tubular structure; the drive cable 33 for driving the flexible joint component 3 to deflect can extend and pass through the flexible joint component 3, and extend into the instrument box 22 through the inside of the instrument tube 23, and be wound and connected to the transmission structure in a specified winding direction. Thus, the instrument box 22 can drive the transmission structure to rotate by starting the power source, thereby retracting or releasing the drive cable 33 by a certain distance, so that the flexible joint component 3 deflects in a specified direction at a specified deflection angle.

[0056] In some embodiments, the instrument tube 23 can also be rotatably mounted on the instrument case 22 to enable the self-rotation of the flexible joint component 3, thereby adjusting the movement orientation of the tool head 21 or the deflection orientation of the flexible joint component 3. In some embodiments, the tool head 21 can also be connected to the transmission structure and power source within the instrument case 22 via a dedicated tool drive cable or other transmission mechanism. Thus, the instrument case 22 can achieve the movement of the tool head 21 (e.g., the gripping of tweezers, the insertion and withdrawal of needles, etc.) or the self-rotation of the instrument tube 23 by activating the power source.

[0057] The instrument tube 23 supports the flexible joint component 3 and the tool head 21 and assists in bending. In some embodiments, the instrument tube 23 may be made of materials such as steel pipe and have a slit cut in the middle section. The length of the instrument tube 23 is determined by the trocar travel of the surgical robot 1, which refers to the distance or range that the surgical instrument (surgical arm 2 or tool head 21) enters the patient's body through the trocar during the operation.

[0058] Please see Figures 3 to 5 , Figure 3 This is a schematic diagram of the overall structure of the flexible joint component 3 shown in some embodiments of this application; Figure 4 This is a schematic diagram of the overall structure of the second flexible joint assembly 32 shown in some embodiments of this application; Figure 5 This is a schematic diagram showing the layout of the constraint cable 34 of the second flexible joint assembly 32 according to some embodiments of this application. Figures 2 to 5 As shown, the flexible joint component 3 may include two flexible joint assemblies 30, namely a first flexible joint assembly 31 and a second flexible joint assembly 32.

[0059] Each flexible joint assembly 30 may include at least one snake-bone joint 4 and at least two drive cables 33. Furthermore, each drive cable 33 extends and passes through each snake-bone joint 4, and the connection position (or passing position) of the drive cable 33 on each snake-bone component 5 (or snake-bone joint 4) is symmetrical based on the pivot 50 of the current snake-bone joint 4. One end of the drive cable 33 may be fixed to the most distal snake-bone component 5 in the corresponding flexible joint assembly 30, where the most distal snake-bone component 5 refers to the snake-bone component 5 closest to the tool head 21 within the same flexible joint assembly 30. Thus, the surgical instrument box 22 can achieve the bending or repositioning of the snake-bone joint 4 to one side and the deflection of the flexible joint assembly 30 to one side by retracting and extending the drive cables 33 on both sides of the snake-bone joint 4, thereby achieving the specified posture of the tool head 21.

[0060] In some embodiments, the flexible joint assembly 30 may further include a connecting straight tube 35. Each end of the connecting straight tube 35 may have at least one serpentine joint 4 (taking the first flexible joint assembly 31 as an example). The connecting straight tube 35 can be used to expand the working space of the flexible joint component 3 or the first flexible joint assembly 31. For example, the connecting straight tube 35 can enable the first flexible joint assembly 31 to achieve a working space of 120mm during deflection. Furthermore, the connecting straight tube 35 can be a perforated steel tube to reduce the overall weight of the flexible joint component 3.

[0061] In some embodiments, each flexible joint assembly 30 can achieve reciprocating deflection in at least two degrees of freedom through a plurality of serpentine joints 4. Further, each flexible joint assembly 30 can include at least two serpentine joints 4 whose bending directions are perpendicular to each other (i.e., the two pivots 50 are perpendicular to each other). Figure 3 As shown, in the first flexible joint assembly 31, each end of the connecting straight tube 35 can be provided with two serpentine joints 4 whose pivot extension direction A (flexible direction) is perpendicular to each other, and the maximum bendable angle of each serpentine joint 4 facing either side can be set to 60 degrees. Furthermore, the serpentine joints 4 arranged at both ends of the connecting straight tube 35 have the same bendable direction; in the second flexible joint assembly 32, multiple serpentine joints 4 can initially be stacked and arranged sequentially in the same straight direction, and the maximum bendable angle of each serpentine joint 4 facing either side can be set to 45 degrees.

[0062] In some embodiments, where any flexible joint assembly 30 includes at least two serpentine joints 4 with the same pivot extension direction A, the flexible joint assembly 30 may further include at least two constraint cables 34. The constraint cables 34 are used to limit the uncertain deformation of the flexible joint assembly 30, so that after directional deflection based on a specified deflection angle, it has a uniquely determined posture, thereby mitigating the problem of uncertain deformation (e.g., S-shaped deformation) of the flexible joint assembly 30 due to external loads.

[0063] Specifically, in the flexible joint assembly 30, each constraint cable 34 extends and passes through multiple serpentine joints 4. The connection positions 340 (passing positions) of the constraint cables 34 on each serpentine member 5 (or serpentine joint 4) are generally symmetrical about the pivot 50. Further, between two serpentine joints 4 that are adjacent in the same pivot extension direction A, the connection position 340 of each constraint cable 34 with the nearest serpentine member 5 (serpentine joint 4) is the first connection position 341, and the connection position 340 of each constraint cable 34 with the farthest serpentine member 5 (serpentine joint 4) is the second connection position 342. The first connection position 341 can be shifted by 180 degrees relative to the second connection position 342 based on the central axis of the flexible joint assembly 30. The 180-degree shift based on the central axis of the flexible joint assembly 30 can be understood as the first connection position 341 and the second connection position 342 being located on opposite sides of the central axis of the flexible joint assembly 30 when the flexible joint assembly 30 is in a straight state without deflection.

[0064] like Figure 4 , Figure 5 As shown, taking the second flexible joint assembly 32 as an example, the second flexible joint assembly 32 may include a first snake-bone joint 401, a second snake-bone joint 402, a third snake-bone joint 403, and a fourth snake-bone joint 404 arranged sequentially along the same straight direction M. The pivot extension directions A of the first snake-bone joint 401 and the second snake-bone joint 402 are perpendicular to each other, the pivot extension directions A of the third snake-bone joint 403 and the fourth snake-bone joint 404 are perpendicular to each other, and the pivot extension directions A of the first snake-bone joint 401 and the fourth snake-bone joint 404 are the same (or parallel to each other).

[0065] Furthermore, the second flexible joint assembly 32 may include four drive cables 33 and four constraint cables 34, all of which extend and pass through each of the snake-bone joints 4. The connection positions or passing positions of the four drive cables 33 and four constraint cables 34 on each snake-bone member 5 may be symmetrical about the pivot 50. Furthermore, one drive cable 33 may be adjacent to one constraint cable 34. The connection position 340 between each constraint cable 34 and the snake-bone member 5 in the first snake-bone joint 401 is the first connection position 341, and the connection position 340 between each constraint cable 34 and the snake-bone member 5 in the fourth snake-bone joint 404 is the second connection position 342. The first connection position 341 is shifted by 180 degrees from the second connection position 342 based on the central axis M of the second flexible joint assembly 32.

[0066] In some embodiments, the first vertical distance between the first connecting position 341 and the central axis M may be equal to the second vertical distance between the second connecting position 342 and the central axis M, so that the two most adjacent snake joints 4 with the same bendable direction have equal bending angles when the flexible joint assembly 30 is deflected; in other embodiments, the first vertical distance between the first connecting position 341 and the central axis M may be greater than or less than the second vertical distance between the second connecting position 342 and the central axis M, so that the two most adjacent snake joints 4 with the same bendable direction have unequal bending angles when the flexible joint assembly 30 is deflected.

[0067] In this embodiment, for two snake joints 4 in the same flexible joint assembly 30 with the same pivot extension direction A (flexible direction) and the closest positions, four constraint cables 34 are connected to the snake joints 4 by a 180-degree shift arrangement based on the central axis M. When the two snake joints 4 with the same pivot extension direction A bend towards the same side based on a specified deflection angle, each can have a fixed bending angle. This is because the length of the four constraint cables 34 is fixed, and the constraint position (i.e., connection position 340 or insertion position) of each constraint cable 34 to each snake joint 4 is fixed. When a constraint cable 34 is pulled to one side by a bending snake joint 4, since the length of each constraint cable 34 remains unchanged and the connection position 340 remains unchanged, the other snake joint 4 will also be pulled by the constraint cable 34 and bend and displace accordingly. The two snake joints 4 can achieve a unique bending angle through the 180° shift arrangement of at least two constraint cables 34 and the constraint connection at the specified position.

[0068] Please see Figures 6 to 7 , Figure 6 This is a schematic diagram of the overall structure of the snake-bone joint 4 shown in some embodiments of this application; Figure 7 This is a schematic diagram of the overall structure of the snake-bone joint 4 according to another embodiment of this application. Figures 6 to 7 As shown, this application embodiment provides a snake bone joint 4, which includes two snake bone components 5, a support structure 41, and at least two traction ropes 52.

[0069] In this embodiment, the snake-bone component 5 refers to a segmental unit used to form the snake-bone joint 4 and support the bending movement of the snake-bone joint 4; the support structure 41 refers to a structure disposed between two snake-bone components 5, which provides support and restricts the centers of the two snake-bone components 5 from moving closer or further apart. In this embodiment, the support structure 41 can be an independent component or integrally formed with the snake-bone component 5. The traction rope 52 refers to a structure that, during the relative rotation of the two snake-bone components 5, or when the two snake-bone components 5 are stationary based on a fixed included angle, can bend to cooperate with the rotation of the snake-bone components 5, while also applying a bidirectional constraint force to the two snake-bone components 5, so as to reduce or even avoid uncertain misalignment and slippage between the snake-bone components 5.

[0070] Specifically, each snake-bone component 5 can rotate based on its own pivot 50. The two pivots 50 in the same snake-bone joint 4 are parallel to each other and have a constant distance between them. The distance between the two pivots 50 is the center distance of the snake-bone joint 4. A support structure 41 is disposed between the two snake-bone components 5 to maintain a constant center distance between them. The pivot 50 can refer to an actual structure in the snake-bone joint 4 or a specific axial position on each snake-bone component 5. In this embodiment, the pivot 50 is the reference axis around which each snake-bone component 5 rotates, typically a straight line position on the snake-bone component 5. In the above technical solution, the snake-bone joint 4 can maintain a constant center distance between the two snake-bone components 5 through the support structure 41, or the cooperation between the support structure 41 and the drive cable 33, thereby effectively improving the bending accuracy and bending stability of the snake-bone joint 4. Furthermore, the support structure 41 can bear part of the pressure load generated when the snake-bone components 5 are tightened by the drive cable 33, thereby reducing wear between the snake-bone components 5, extending their service life, and improving the bending accuracy of the snake-bone joint 4. In this embodiment, the two snake-bone components 5 in the snake-bone joint 4 can rotate up to ±90°.

[0071] Furthermore, the traction ropes 52 are pre-tensioned and connected between the two snake-bone components 5. At least one pair of traction ropes 52 are projected in a cross-symmetrical manner in the pivot extension direction A. Each snake-bone component 5 includes a limiting arc surface 53 for tensioning the traction ropes 52, and each snake-bone component 5 includes a rotating base 51 for threading the drive cable 33. The end faces of the two adjacent and opposite rotating bases 51 in the same snake-bone joint 4 are the first end faces 510. The limiting arc surface 53 is disposed on the first end face 510 of the rotating base 51, and the axis of the limiting arc surface 53 is parallel to or coincides with the pivot 50. The limiting arc surfaces 53 that the same pair of traction ropes 52 are in close contact with have equal radii, and the starting end 530 of the limiting arc surface is fixed to the end of the traction rope 52.

[0072] Please combine Figures 12 to 13As shown, in the same snake-bone joint 4, with the two pivots 50 parallel and the distance between them constant, at least one pair of traction ropes 52 are connected between the two snake-bone components 5 in a pre-tensioned state. Their projections along the extension direction of the pivots are cross-symmetrical, and both are tensioned by limiting arc surfaces 53 of equal radius on the two snake-bone components 5. This is the premise for the two snake-bone components 5 to achieve symmetrical rotation based on the constraint of the traction ropes 52. If the same pair of traction ropes 52 are tensioned by limiting arc surfaces 53 of different radii on the two snake-bone components 5, the bending changes of the two traction ropes 52 in the pre-tensioned state when the two snake-bone components 5 rotate relative to each other cannot be symmetrical based on the tangent line B of the reference circle 500. Consequently, the rotation angles of the two snake-bone components 5 based on their respective pivots 50 are not equal, and the two snake-bone components 5 cannot maintain symmetrical rotation.

[0073] Based on this, without using the pre-tightening engagement of the traction rope 52 and the limiting arc surface 53 to restrict the snake bone component 5 from sliding misaligned to either side, the flexible joint assembly 30 and the snake bone joint 4 do not have a uniquely determined posture when bending based on a specified bending angle. Furthermore, assuming the snake bone joint 4 completes the bending action based on a specified bending angle (60 degrees), and the two snake bone components 5 achieve the bending of the snake bone joint 4 in an ideal state—for example, the two snake bone components 5 rotate towards each other based on their respective pivots 50, each rotating 30 degrees—when the surgical arm 2 performs surgical operations based on the snake bone joint 4 in this posture, the snake bone joint 4 may still change to other postures due to external force interference, i.e., uncertain deformation occurs. For example, when the tool head 21 contacts an organ or blood vessel during insertion into the human body, the contact pressure is transmitted from the tool head 21 to the snake joint 4. The two snake components 5 will change from rotating 30 degrees to one rotating 20 degrees and the other 40 degrees, causing the snake joint 4 to change to other postures. This makes it impossible for the tool head 21 to apply force to the surgical target position to perform the surgical operation, and may even cause incorrect wounds due to a sudden change in the surgical target position caused by external force. Therefore, at least one pair of traction ropes 52 is needed between the snake components 5 constituting the flexible snake joint 4 to apply bidirectional constraint force to the limiting arc surface 53 and the snake components 5 to achieve a symmetrical motion configuration, thereby reducing the probability of uncertain deformation (which can be called S-shaped deformation or parallelogram deformation) of the snake joint 4 due to external force. Under the symmetrical motion configuration, the two snake components 5 rotate towards each other with equal rotation angles.

[0074] Please combine Figures 12 to 13As shown, the projections of the two traction ropes 52 connected between the snake-bone components 5 in the pivot extension direction A are intersecting. The two traction ropes 52 are identical in size, material, cross-sectional shape, and other characteristics. The ends of the traction ropes 52 are fixedly connected to the starting ends 530 of the limiting arc surfaces. Each traction rope 52 is at least partially wrapped around the limiting arc surfaces 53 of the two snake-bone components 5 and tensioned by the limiting arc surfaces 53. When the radii of the limiting arc surfaces 53 of the two snake-bone components 5 are equal, the projections of the intersecting traction ropes 52 are symmetrical based on the reference circle tangent line B between the two snake-bone components 5, regardless of the degree to which the snake-bone components 5 rotate. The reference circle tangent line B usually refers to the perpendicular bisector of the line connecting the center points of the two pivots 50 (the reference circle tangent line B is also the normal to the plane where the two pivots 50 are located). Therefore, when the two snake-bone components 5 rotate to a certain angle, the pre-tensioned traction ropes 52 on both sides of the pivot 50 apply a restraining force to each other. Regardless of which side the snake-bone components 5 tend to slide out of alignment, they will be basically restrained and limited by the pre-tensioned traction ropes 52. Thus, the above scheme reduces the probability of uncertain deformation of the snake-bone joint 4 due to external loads and improves the bending accuracy and load deformation resistance of the snake-bone joint 4.

[0075] In the above technical solution, when the two pivots 50 corresponding to the same snake joint 4 are parallel to each other and the distance between them is constant, the snake joint 4 can be configured with at least a pair of traction ropes 52 arranged in a cross-symmetrical state. Each traction rope 52 is connected between the two snake components 5 in a pre-tightened state. Each traction rope 52 is tensioned by a limiting arc surface 53 with equal radius and axis that coincides with or is parallel to the pivot 50, and its end is fixed to the starting end of the limiting arc surface 53. This allows the two snake components 5 to rotate relative to each other based on a specified bending angle of the snake joint 4. The traction ropes 52 in the pre-tightened state can apply relative and equal constraint forces to the two snake components 5. This enables the snake joint 4 to achieve a symmetrical motion configuration during bending and has a unique shape at the specified bending angle. This reduces the probability of uncertain misalignment and slippage between the snake components 5 and ultimately improves the bending accuracy and load deformation resistance of the snake joint 4. In addition, the traction rope 52 is pre-tensioned and connected between the two snake-bone components 5. It can bear part of the load when the two snake-bone components 5 rotate relative to each other due to the tension of the drive cable 33, thereby saving the output force required for the drive cable 33 to be wound and released, and reducing the deformation of the drive cable 33.

[0076] In some embodiments, in the snake-bone joint 4, the radius of the limiting arc surface 53 does not exceed half of the center distance H. In the above technical solution, having the radius of the limiting arc surface 53 not exceed half of the center distance helps reduce the processing difficulty of the snake-bone component 5 and the assembly difficulty of the snake-bone joint 4, improving the smoothness of the bending of the snake-bone joint 4. Furthermore, the range of values ​​for the radius R of the limiting arc surface 53 in each snake-bone component 5 can be:

[0077] Please see Figures 8 to 9 , Figure 8 This is an exploded schematic diagram of the snake-bone joint 4 shown in some embodiments of this application; Figure 9 This is an exploded view of the snake-like joint 4 shown in other embodiments of this application. For example... Figures 8 to 9 As shown, on the same snake-bone component 5, the limiting arc surface 53 may include a first arc surface 531 and a second arc surface 532. The first arc surface 531 is used to tension one traction rope 52, and the second arc surface 532 is used to tension another traction rope 52. Further, the first arc surface 531 and the second arc surface 532 are connected and partially overlap to form a semi-circular arc surface. Specifically, in the same snake-bone joint 4, the semi-circular arc surfaces on the two snake-bone components 5 maintain a symmetrical state during the bending process of the snake-bone joint 4. The symmetry reference plane can be the normal plane of the line connecting the center points of the two pivots 50 (the projection of the symmetry reference plane onto...). Figure 12 , 13 (represented by the tangent line B of the reference circle).

[0078] In the above technical solution, the two limiting arc surfaces 53 used to tension the first traction rope 521 and the second traction rope 522 can be connected or partially overlapped to form a semi-circular arc surface, which makes the structure of the snake bone component 5 simpler and more compact, and more conducive to processing and assembly. In some other embodiments, a pair of traction ropes 52 can be tensioned by different limiting arc surfaces 53, which can also reduce the probability of uncertain misalignment deformation between the snake bone components 5 and improve the bending accuracy and load deformation resistance of the snake bone joint 4.

[0079] like Figure 8 As shown, in the snake-bone joint 4, each end of the pivot 50 can be provided with a pair of traction ropes 52 that are arranged adjacently with their projections in a cross-symmetrical manner. In the above technical solution, along the pivot extension direction A, each side of the snake-bone joint 4 is restricted from misalignment and deformation between the snake-bone components 5 by at least a pair of traction ropes 52 arranged in a pre-tensioned state, which can improve the stability, consistency and reliability of the bending of the snake-bone joint 4, and can bear external loads more evenly.

[0080] like Figure 8As shown, the support structure 41 may include at least one connecting pin assembly 43. Each connecting pin assembly 43 may include at least one connecting pin 431, and each connecting pin 431 may include two connecting pin shafts 4311 and a connecting rod 4312. The connecting rod 4312 is vertically connected between the two parallel connecting pin shafts 4311 and may be integrally formed with the connecting pin shafts 4311. In the same snake joint 4, one connecting pin shaft 4311 is rotatably connected to one snake member 5, and the axis of one connecting pin shaft 4311 is fixedly aligned with the pivot 50 of one snake member 5. In the above technical solution, the snake joint 4 fixes the center distance between the two snake members 5 through the connecting pins 431, making it difficult for the two snake members 5 to approach or move away from each other during the rotation process, thereby improving the bending accuracy and bending reliability of the snake joint 4.

[0081] Furthermore, each connecting pin assembly 43 may include two connecting pins 431 and an anti-detachment component 432. The anti-detachment component 432 is disposed between the two connecting pins 431 and achieves connection, synchronous rotation and anti-detachment in the pivot extension direction A by engaging with the limiting groove and the limiting insert plate.

[0082] like Figure 9 As shown, the traction rope 52 may include a first traction rope 521 and a second traction rope 522. The projections of the first traction rope 521 and the second traction rope 522 on the pivot extension direction A are symmetrically arranged. In the snake joint 4, the first traction rope 521 is located at one end of the pivot 50, and the second traction rope 522 is located at the other end of the pivot 50. In the above technical solution, the first traction rope 521 and the second traction rope 522 are respectively located on both sides of the snake joint 4, which can also improve the stability and reliability of the bending of the snake joint 4, and can bear the external load more evenly.

[0083] In other embodiments, a pair of traction ropes 52 includes a first traction rope 521 and a second traction rope 522. In the snake joint 4, the pair of traction ropes 52 may be provided only at one end of the pivot 50, that is, the first traction rope 521 and the second traction rope 522 are provided at only one end of the pivot 50; or, the first traction rope 521 and the second traction rope 522 are provided at one end of the pivot 50, and only the first traction rope 521 or the second traction rope 522 is provided at the other end; or, the first traction rope 521 and the second traction rope 522 are provided at one end of the pivot 50 with their projections in a cross-symmetrical state, and the third traction rope and / or the fourth traction rope are provided at the other end of the pivot 50. The radius of the limiting arc surface 53 used to tension the first traction rope 521 and the second traction rope 522 may be greater than or less than the radius of the limiting arc surface used to tension the third traction rope or the fourth traction rope.

[0084] In some embodiments, the surfaces of two snake bone members 5 in the same snake bone joint 4 that are opposite to each other and adjacent to each other are first end faces 510. Each support structure 41 may include two arc-shaped top units 42. In the same snake bone joint 4, the arc-shaped top units 42 may be respectively disposed on the first end faces 510 of the two snake bone members 5 that are opposite to each other and adjacent to each other, and may be integrally formed with the snake bone members 5.

[0085] Each arc-shaped top unit 42 has an arc-shaped top surface 420. Two arc-shaped top surfaces 420 are arranged opposite each other, rolling in contact, and have equal radii. One arc-shaped top surface 420 is located on the first end face 510 of one snake-bone component 5, and the other arc-shaped top surface 420 is located on the first end face 510 of another snake-bone component 5. The axis of the arc-shaped top surface 420 coincides with the pivot 50, and the radius of the arc-shaped top surface 420 is equal to half the center distance of the snake-bone joint 4. In the above technical solution, the arrangement of the arc-shaped top surfaces 420 can reduce the wear of the snake-bone component 5, and the rolling contact between the arc-shaped top surfaces 420 can improve the smoothness of the bending of the snake-bone joint 4 and the stability of the structure, improve the load-bearing capacity of the snake-bone component 5, and reduce the processing difficulty of the snake-bone component 5.

[0086] Furthermore, when the radius of the limiting arc surface 53 is equal to half the center distance H, the top surface 420 of the arc can coincide with the limiting arc surface 53, that is, they can be represented by the same semi-circular arc surface. The semi-circular arc surface convexes outward relative to the first end face 510, and both ends of the semi-circular arc surface extend onto the first end face 510. In the above technical solution, the coincidence of the top surface 420 of the arc and the limiting arc surface 53 can improve the simplicity of the snake bone component 5 structure and reduce the processing difficulty of the snake bone component 5.

[0087] In some embodiments, in the same support structure 41, at least one side of the top surface 420 of an arc is provided with a retaining edge 421. The limiting direction corresponding to the retaining edge 421 is the same as the pivot extension direction A, and the radius corresponding to the retaining edge 421 is greater than half of the center distance H. In the above technical solution, the retaining edge 421 provided on at least one side of the top surface 420 of the arc can reduce the probability of the snake bone components 5 moving along the pivot 50 during the bending process of the snake bone joint 4, and improve the bending accuracy of the snake bone joint 4.

[0088] In the above technical solution, the snake joint 4 can fix the center distance H between the two snake components 5 through various types of support structures 41, so that the pivots 50 of the two snake components 5 are difficult to approach or move away from each other during the rotation process (the cooperation of the arc-shaped top unit 42 and the drive cable 33 to tighten and connect several snake components 5 can make it difficult for the snake components 5 to move away from or approach each other, and the connecting pin assembly 43 can also play the same role). The constant center distance ensures that the centers of the snake components 5 will not suddenly approach or move away from each other under the tension of the drive cable 33, thereby reducing the probability of the snake joint 4 being "accidentally impacted" or "dislocated".

[0089] In some embodiments, the surfaces of the two snake-bone components 5 in the snake-bone joint 4 that are opposite to each other and adjacent to each other are first end faces 510. On either first end face 510, along a direction perpendicular to the pivot 50, both ends of the first end face 510 are provided with limiting inclined surfaces 512 that are inclined relative to the first end face 510 and have equal inclination angles. In the above technical solution, the setting of the limiting inclined surfaces 512 can limit the maximum rotation angle of the snake-bone component 5 towards one side, that is, limit the maximum bending angle of the snake-bone joint 4 towards one side, reduce edge collisions and wear between the snake-bone components 5, and extend the service life of the snake-bone components 5.

[0090] Please see Figure 10 , Figure 10 This is a front view schematic diagram of the snake-bone joint 4 shown in some embodiments of this application. For example... Figure 10 As shown, when the radius of the limiting arc surface 53 is equal to half the center distance H, the limiting arc surface 53 is provided with a buried groove 533 of uniform depth, which is used to accommodate the traction rope 52. Furthermore, the depth of the buried groove 533 can be greater than the diameter of the traction rope 52 in the pre-tensioned state. In the above technical solution, when the radius of the limiting arc surface 53 is equal to half the center distance H, the limiting arc surfaces 53 of the two snake-bone components 5 abut and roll in contact, placing the traction rope 52 in the buried groove 533. This balances the constraint of the traction rope 52 on the snake-bone component 5 with the simplification of the overall structure of the snake-bone joint 4, and also reduces the wear of the traction rope 52, extending the service life of the snake-bone joint 4.

[0091] Please combine Figure 4As shown, in the same snake-bone joint 4, the axis of the limiting arc surface 53 coincides with or is parallel to the pivot 50. The snake-bone component 5 may include two first end faces 510 that are opposite to each other. The limiting arc surfaces 53 respectively provided on the two first end faces 510 of the same snake-bone component 5 have their corresponding axes (pivots 50) perpendicular to each other. In the above technical solution, one snake-bone component 5 can be used simultaneously in the assembly of two snake-bone joints 4 with mutually perpendicular bending directions, thereby forming a double snake-bone joint 40 that can achieve bidirectional bending. The embodiments of this application improve the compactness and simplicity of the overall structure of the snake-bone joint 4 and can save on the processing materials of the snake-bone component 5.

[0092] Please see Figure 11 , Figure 11 This is a schematic cross-sectional view of the traction rope 52 shown in some embodiments of this application. For example... Figure 11 As shown, the traction rope 52 may include at least one flexible traction wire 520, the cross-sectional shape of which is circular or rectangular. In the above technical solution, the flexible traction wire 520 with a circular cross-section experiences more uniform force and is conducive to reducing wear, while the flexible traction wire 520 with a rectangular cross-section has higher strength and torsional resistance, and is conducive to applying directional constraint force. The combination of multiple flexible traction wires 520 can increase structural strength and is conducive to uniform load distribution.

[0093] Specifically, the flexible traction wire 520 is made of a metallic or non-metallic material with good tensile strength. The terminals at both ends of the traction rope 52 (i.e., the ends of the traction rope 52) can be fixed in an inlay manner to the starting ends 530 of the upper limit arc surfaces of the two snake-bone components 5 (see [link to relevant documentation]). Figures 12 to 13 The slots at points a, b, c, and d are fixedly connected to the two snake-bone components 5.

[0094] Please see Figures 12 to 13 , Figure 12 This is a schematic diagram illustrating the geometric principle of the symmetrical motion configuration of the snake-bone joint 4 as shown in some embodiments of this application; Figure 13 This is a schematic diagram illustrating the geometric principle of the symmetrical motion configuration of the snake-bone joint 4 as shown in other embodiments of this application. Please refer to... Figures 6 to 13 As shown, each snake bone component 5 includes multiple sets of rope holes 511, which are symmetrically arranged on both sides of the pivot 50. Each rope hole 511 is located on the first end face 510 and extends in a direction perpendicular to the first end face 510. The rope hole 511 is used to accommodate the drive cable 33 or the restraint cable 34.

[0095] Furthermore, multiple threading holes 511 for threading or connecting the drive cables 33 can be symmetrically arranged on both sides of the pivot 50. For example, each side of the pivot 50 is provided with two threading holes 511 for connecting the drive cables 33, and the snake joint 4 can achieve a bending action towards one side by tightening and loosening the two drive cables 33.

[0096] In the above technical solution, the arrangement of multiple sets of rope holes 511 makes the overall structure of the snake joint 4 and the flexible joint component 30 more compact, and also reduces the pulling and interference on the restraint cable 34 or drive cable 33 when the snake component 5 rotates. Furthermore, the symmetrical arrangement of the rope holes 511 ensures that the connection positions of the drive cables 33 on both sides of the snake joint 4 and each snake component 5 are symmetrical and equidistant based on the pivot 50. When the snake joint 4 can achieve a symmetrical motion configuration, the symmetrical arrangement of the rope holes 511 enables the drive cables 33 on both sides of the snake joint 4 to achieve consistent extension and retraction with balanced lever arms, thereby extending the service life of the drive cables 33.

[0097] like Figures 12 to 13 As shown, when the connection positions (penetration positions) of the drive cables 33 on both sides of the snake joint 4 with each snake component 5 are symmetrical and equidistant from the pivot 50, the snake joint 4, which bends from a straight state to any angle, can form an isosceles trapezoid (or an isosceles triangle in extreme cases) motion configuration with the drive cables 33. When the drive cables 33 on both sides of the snake joint 4 are pulling the snake joint 4 to bend, the shortening length of one side of the cable is equal to the elongation length of the other side of the cable, that is, the drive cables 33 on both sides of the snake joint 4 extend and retract in the same way.

[0098] Furthermore, the perpendicular distance between the projection intersection point O of the drive cables 33 on both sides of the pivot 50 and the traction rope 52 can be considered as the lever arm corresponding to the tightening of the drive cable 33 when the snake joint 4 is in any posture, and the drive cable 33 on one side drives the snake joint 4 to continue bending or returning to its original position (or it can be considered as the drive cable 33 driving the snake joint 4 to bend towards either side). Figure 12 , Figure 13For example, in the illustrated posture, the lever arm required for the left drive cable 33 to tighten and drive the snake joint 4 to continue bending to the left is equal to the lever arm required for the right drive cable 33 to tighten and drive the snake joint to return to a straight position to the right. This state of equal lever arm can be considered as lever arm balance. That is, regardless of the posture of the snake joint 4 or which side it is about to bend, the force required to tighten the drive cables 33 on both sides of the snake joint 4 is equal. As a result, the probability of deformation of the drive cables 33 on both sides of the snake joint 4 is reduced, and the problem of excessive difference in force deformation of the drive cables 33 on both sides due to the long-term accumulation of lever arm imbalance is effectively alleviated. This reduces the wear of the drive cables 33, increases their service life, and improves the consistency of the service life of each drive cable 33.

[0099] In some embodiments, the double snake joint 40 can be formed by connecting and interleaving two snake joints 4 that are perpendicular to each other in the pivot extension direction A. Furthermore, each snake joint 4 can bend up to 90° in any direction. Four drive cables 33 are symmetrically arranged on both sides of the pivot 50 of each snake joint 4, and the four drive cables 33 can be evenly distributed circumferentially on the first end face 510 of each snake member 5. The retraction of every two adjacent drive cables 33 corresponds to the bending of the snake joint 4 to one side, thereby enabling the snake joint 4 to bend in four directions around two straight lines, with each straight line corresponding to bending in both directions.

[0100] Please see Figure 14 , Figure 14 This is a schematic diagram illustrating the geometric principle of a partial structure of the snake-bone joint 4 as shown in some embodiments of this application. For example... Figure 14 As shown, taking the first traction rope 521 and the first arc surface 531 on the two snake-bone components 5 used to tension the first traction rope 521 as an example, since the traction rope 52 tensioned on the limiting arc surface 53 has the largest wrapping angle on the limiting arc surface 53 when the snake-bone joint 4 is bent to the limit angle, the circumferential extension angle of the limiting arc surface 53 is related to the maximum wrapping angle α. The larger the radius of the first arc surface 531, the larger the circumferential extension angle of the first arc surface 531 (which can be understood as the minimum angle of the limiting arc surface 53 extending circumferentially around the pivot 50). Therefore, in the snake-bone joint 4, the larger the radius of the first arc surface 531 and the second arc surface 532, the larger the circumferential extension angle of the first arc surface 531 and the second arc surface 532.

[0101] In this embodiment, when the maximum bendable angle of the snake joint 4 is determined, the circumferential extension angle of each limiting arc surface 53 is related to the radius of the limiting arc surface 53, so that the traction rope 52 always passes through the tension of the limiting arc surface 53, and applies a constraint force to the two snake components 5 to restrict their misalignment and sliding, thereby reducing the probability of misalignment deformation and improving the bending accuracy and load deformation resistance of the snake joint 4.

[0102] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A snake-bone joint, comprising two snake-bone components and at least one support structure, each of the snake-bone components being rotatable about its respective pivot, the support structure being disposed between the two snake-bone components, and the two pivots in the same snake-bone joint being parallel and having a constant distance between them; characterized in that, The snake-bone joint also includes: At least two traction ropes are connected between two snake-bone components in a pre-tensioned state, and the projections of at least one pair of traction ropes in the pivot extension direction are cross-symmetrical; each snake-bone component includes a limiting arc surface for tensioning the traction rope, the axis of the limiting arc surface is parallel to or coincides with the pivot, the limiting arc surfaces that the same pair of traction ropes are in close contact with have equal radii, and the starting end of the limiting arc surface is fixed to the end of the traction rope.

2. The snake-bone joint according to claim 1, characterized in that, In the snake-bone joint, the distance between the two pivots is the center distance of the snake-bone joint; the radius of each limiting arc surface does not exceed half of the center distance.

3. The snake-bone joint according to claim 2, characterized in that, When the radius of the limiting arc surface is equal to half of the center distance, a buried wire groove is provided on the limiting arc surface, and the buried wire groove is used to accommodate the traction rope.

4. The snake-bone joint according to claim 2, characterized in that, On the same snake-bone component, the limiting arc surface includes a first arc surface and a second arc surface. The first arc surface is used to tension one of the traction ropes, and the second arc surface is used to tension the other traction rope. The larger the radius of the first arc surface and the second arc surface, the larger the circumferential extension angle of the first arc surface and the second arc surface.

5. The snake-bone joint according to claim 4, characterized in that, On the same snake-bone component, the first arc surface and the second arc surface are connected or partially overlapped to form a semi-circular arc surface.

6. The snake-bone joint according to any one of claims 1-5, characterized in that, In the snake-bone joint, each end of the pivot is provided with a pair of traction ropes arranged in a cross-symmetrical pattern.

7. The snake-bone joint according to any one of claims 1-5, characterized in that, The traction rope includes a first traction rope and a second traction rope, and the projections of the first traction rope and the second traction rope in the direction of the pivot extension are in a cross-symmetrical state. In the snake-bone joint, the first traction rope is located at one end of the pivot, and the second traction rope is located at the other end of the pivot.

8. The snake-bone joint according to any one of claims 1-5, characterized in that, The traction rope includes at least one flexible traction wire, the cross-sectional shape of which is circular or rectangular.

9. The snake-bone joint according to any one of claims 1-5, characterized in that, The snake-bone component includes two first end faces that are opposite to each other, and the pivots corresponding to the limiting arc surfaces respectively provided on the two first end faces are perpendicular.

10. The snake-bone joint according to any one of claims 1-5, characterized in that, In the snake-bone joint, the surfaces of the two snake-bone components that are opposite to each other and adjacent to each other are the first end faces; Each of the support structures includes two rolling contact circular arc surfaces with equal radii, one of which is located on the first end face of one of the snake-bone components, and the other is located on the first end face of another snake-bone component. The axis of the circular arc surfaces coincides with the pivot.

11. The snake-bone joint according to claim 10, characterized in that, The radius of the arc opposite the top surface is equal to half the center distance of the snake joint; when the radius of the limiting arc surface is equal to half the center distance, the arc opposite the top surface coincides with the limiting arc surface.

12. The snake-bone joint according to claim 10, characterized in that, In the same support structure, at least one side of the top surface of one of the arcs is provided with a stop, and the limiting direction corresponding to the stop is the same as the extension direction of the pivot.

13. The snake-bone joint according to any one of claims 1-5, characterized in that, The support structure includes at least one connecting pin, each connecting pin including two connecting pin shafts and a connecting rod, the connecting rod being vertically connected between two mutually parallel connecting pin shafts; In the snake-bone joint, the connecting pins correspond one-to-one with the snake-bone components and are rotatably connected, and the axis of the connecting pins coincides with the pivot.

14. The snake-bone joint according to any one of claims 1-5, characterized in that, Each of the snake-bone components includes multiple sets of rope holes, which are symmetrically arranged on both sides of the pivot. The rope holes are used to accommodate drive cables or restraint cables.

15. The snake-bone joint according to any one of claims 1-5, characterized in that, In the snake joint, the surfaces of the two snake components that are opposite to each other and adjacent to each other are first end faces; on either of the first end faces, in a direction perpendicular to the pivot, both ends of the first end face are provided with limiting inclined surfaces that are inclined relative to the first end face and have equal inclination angles.

16. A flexible joint assembly, characterized in that, The flexible joint assembly includes: At least one snake-bone joint as described in any one of claims 1-15; At least two drive cables, each of which extends and passes through each of the snake-bone joints, with one end of each drive cable fixed to the most distal snake-bone member of the flexible joint assembly.

17. The flexible joint assembly according to claim 16, characterized in that, The flexible joint assembly includes at least two snake joints with the same pivot extension direction, and the flexible joint assembly also includes at least two constraint cables, each of which extends and passes through each of the snake joints, and the connection positions of the constraint cables on the snake member are symmetrical about the pivot. Between the two snake joints that extend in the same direction and are adjacent in position, the connection position of each constraint cable to the nearest snake joint is a first connection position, and the connection position of each constraint cable to the farthest snake joint is a second connection position. The first connection position is shifted by 180° relative to the second connection position based on the central axis of the flexible joint assembly.

18. A surgical operating arm, characterized in that, The surgical arm includes at least one flexible joint assembly as described in claim 16 or 17.

19. A surgical robot, characterized in that, The surgical robot includes at least one surgical arm as described in claim 18.

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