A rigid-flexible dual-drive snake-like surgical robot

Abstract

The application discloses a rigid-flexible dual driving snake-shaped surgical robot, which comprises a rigid dual driving mechanism, a rear-end flexible continuum mechanism, a tendon constraint structure and a front-end flexible continuum mechanism. The rear-end flexible continuum mechanism and the front-end flexible continuum mechanism are associated with each other in terms of tendon length to form a dual continuum mechanism; the rigid dual driving mechanism is associated with the rear-end flexible continuum mechanism in terms of end surface movement, and the rear-end flexible continuum mechanism can be driven to bend, rotate and stretch in any direction by the rigid dual driving mechanism, so that the front-end flexible continuum mechanism is coupled to bend, rotate and stretch in any direction. The application can avoid directly pushing and pulling the driving tendon of the flexible continuum, thereby reducing the driving complexity when the number of tendons is large, and the rigid-flexible dual driving further guarantees the modeling accuracy of the continuum, and has the advantages of high reliability, compact structure and easy realization.

Description

Technical Field

[0001] This invention relates to a mechanical transmission structure, specifically to a serpentine surgical robot with rigid-flexible dual drive. Background Technology

[0002] Minimally invasive surgical techniques, which result in less trauma and higher postoperative outcomes for patients, have come to occupy an important position in surgical procedures. These techniques utilize surgical tools, including illumination and observation instruments and manipulators, to reach the surgical site through natural body cavities or incisions. Current surgical instruments primarily employ a series-hinged structure, driven by steel cable tension, enabling bending motion at the hinge points. However, their flexibility is limited, and further miniaturization is difficult.

[0003] Compared to traditional series hinge structures, flexible continuum structures possess multiple degrees of freedom of motion, including rotation, bending, and extension, offering greater flexibility. Furthermore, the main body of the structure simultaneously serves as the drive transmission structure, enabling more compact designs. Consequently, flexible continuum structures have gradually become an advanced solution for minimally invasive surgical instruments and are widely used in surgical instruments such as flexible manipulators, endoscopes, and controllable catheters.

[0004] Existing flexible continuum structures mainly achieve flexible movement by directly pushing and pulling the driving tendons through the driving mechanism. However, the high requirements for the motion accuracy and stability of flexible continuum structures require an increase in the number of driving tendons, which will correspondingly increase the number and complexity of the driving mechanism, thereby increasing the cost and size. Summary of the Invention

[0005] To address the aforementioned problems, one objective of this invention is to provide a rigid-flexible dual-drive snake-like surgical robot that can achieve overall drive of a flexible continuum. Its drive complexity is not affected by the number of driving tendons. At the same time, the rigid-flexible dual-drive further ensures the modeling accuracy of the continuum, and has the advantages of high reliability, compact structure, and ease of implementation.

[0006] To address the shortcomings of existing technologies, the present invention adopts the following technical solution: a rigid-flexible dual-driven snake-like surgical robot, comprising: a rigid dual-driven mechanism, a rear flexible continuum mechanism, a tendon constraint structure, and a front flexible continuum mechanism;

[0007] Both the rear flexible continuum mechanism and the front flexible continuum mechanism internally constrain the tendons through laminated units, and the tendon lengths are correlated to form a dual continuum mechanism.

[0008] The tendon constraint structure is used to constrain and guide the tendon between the rear flexible continuum mechanism and the front flexible continuum mechanism. It is also provided with several surgical instrument channels, which extend from the tendon constraint structure to the end of the front flexible continuum mechanism.

[0009] The rigid dual drive mechanism is associated with the end face motion of the rear flexible continuum mechanism. The rigid dual drive mechanism drives the rear flexible continuum mechanism to bend, rotate, and extend in any direction, thereby coupling and driving the front flexible continuum mechanism to bend, rotate, and extend in any direction.

[0010] Furthermore, the rigid dual drive mechanism includes: a base, a moving component, and at least three sets of parallel rotating components;

[0011] The rotating assembly includes: a bottom radial swing arm, a bottom middle connecting rod, a top middle connecting rod, and a top radial swing arm;

[0012] The base and the moving component are respectively constrained by through-hole hinges with the bottom radial swing arm and the top radial swing arm; the bottom radial swing arm is constrained by through-hole hinges with the bottom middle connecting rod; the top radial swing arm is constrained by through-hole hinges with the top middle connecting rod; and the bottom middle connecting rod is constrained by through-hole hinges with the top middle connecting rod.

[0013] Furthermore, in the rotating assembly, the hinge axis of the bottom radial rocker arm intersects the base and the hinge axis of the bottom connecting rod at the rotation center of the base; the hinge axis of the top radial rocker arm intersects the moving part and the hinge axis of the top connecting rod at the rotation center of the moving part; the structures of each set of rotating assemblies in the rigid dual drive mechanism are completely identical; the included angle between the two hinge axes of the bottom radial rocker arm is equal to the included angle between the two hinge axes of the top radial rocker arm; the spatial positional relationship between the two hinge axes of the bottom connecting rod and the two hinge axes of the top connecting rod is the same.

[0014] Furthermore, the moving component includes a fixedly connected moving base and a pressure plate. The upper surface of the moving base is provided with tendon guide grooves and tendon holes, which correspond one-to-one. After the tendon passes through the corresponding guide grooves and holes, it is pressed tightly by the fixed connection between the moving base and the pressure plate.

[0015] Furthermore, the rear flexible continuum mechanism includes: a top fixing member, a bottom fixing member, a plurality of rear continuum laminate units, and a rear tendon;

[0016] Each of the rear continuum stacked units includes a rear planar stack and several rear C-shaped stacks; the rear C-shaped stacks are mounted on the rear planar stack, the rear planar stack has several tendon constraint holes, the rear C-shaped stack is in the shape of the letter C and is manufactured by a bending process, and has several tendon constraint holes corresponding to the rear planar stack, the bent part serves as the elastic structure of the continuum;

[0017] The top fixing member is sequentially connected to a plurality of the rear continuous stacked units and the bottom fixing member through a plurality of the rear tendons, and the tendons are fixedly connected to the top fixing member; the motion base is fixedly connected to the top fixing member; and the base is fixedly connected to the bottom fixing member.

[0018] Furthermore, the front-end flexible continuum mechanism includes: an end-end fixing member, a plurality of front-end continuum laminate units, and a front-end tendon;

[0019] The front-end continuous lamination unit includes a front-end planar lamination and several front-end C-shaped laminations;

[0020] Each of the aforementioned front-end continuum stacked units includes a front-end planar stacked unit and several front-end C-shaped stacked units; the front-end C-shaped stacked units are mounted on the front-end planar stacked unit, the front-end planar stacked unit has several tendon constraint holes, the front-end C-shaped stacked units are in the shape of the letter C and are manufactured by a bending process, and have several tendon constraint holes corresponding to the front-end planar stacked units, the bent part serves as the elastic structure of the continuum;

[0021] The end fixation member is sequentially connected to a plurality of the front continuous laminate units through a plurality of the front tendons, and the front tendons are fixedly connected to the end fixation member.

[0022] Furthermore, the tendon constraint structure includes: a bending constraint structure and an elongation constraint structure;

[0023] The bending constraint structure includes a bending constraint inner core and a bending constraint outer shell; the extension constraint structure includes an extension constraint inner core and an extension constraint outer shell.

[0024] The bending constraint inner core and the bending constraint outer shell are fixedly connected; the extension constraint inner core and the extension constraint outer shell are fixedly connected; the second bending constraint outer shell and the extension constraint outer shell are fixedly connected; and the bending constraint inner core is fixedly connected to the base.

[0025] Furthermore, the cross-sectional diameter of the bending constraint structure along its bending direction is smallest at both ends and gradually expands in the middle; the tendon spacing is largest at the point where its cross-sectional radius is largest, thereby creating a surgical instrument channel therein.

[0026] Furthermore, the number of tendons and the included angle between each tendon are exactly the same in the rear flexible continuum mechanism and the front flexible continuum mechanism, and the tendons in the two mechanisms are the same number of tendons.

[0027] Furthermore, the radius of the rear flexible continuum mechanism is larger than the radius of the front flexible continuum mechanism, so that when the length changes of the tendons at the front and rear ends are the same, the bending radius of the front end is larger.

[0028] The present invention, employing the above technical solution, has the following advantages: 1. The rear flexible continuum mechanism and the front flexible continuum mechanism in the present invention are connected by tendon length to form a dual continuum mechanism; the rigid dual drive mechanism is motion-connected with the end face motion of the rear flexible continuum mechanism. Through the rigid dual drive mechanism, the rear flexible continuum mechanism can be driven to bend, rotate, and extend in any direction, thereby coupling and driving the front flexible continuum mechanism to bend, rotate, and extend in any direction. This achieves overall driving of the flexible continuum, with a compact and easily implemented drive structure, which is beneficial for miniaturization and cost reduction of surgical instruments. 2. The rigid dual drive mechanism in the present invention has three degrees of freedom, enabling bending, rotation, and extension in any direction. Furthermore, its base and moving parts always pass through the curvature center of the rear flexible continuum, thus applying a certain degree of equal curvature constraint to the deformation of the rear flexible continuum during driving, which is beneficial for improving the motion accuracy and reliability of the flexible continuum robotic arm. 3. The tendon constraint structure in this invention provides guidance and constraint for the tendon, which helps to ensure the accuracy of motion transmission between the front and rear ends of the dual continuum. Furthermore, the bending constraint structure and the extension constraint structure facilitate the arrangement of various observation and manipulation instruments inside the flexible continuum robotic arm, and can be widely used in the research and development of minimally invasive surgical medical devices. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention;

[0030] Figure 2 This is a schematic diagram of the rigid dual drive mechanism in Embodiment 1 of the present invention;

[0031] Figure 3 This is a schematic diagram of the flexible continuum robotic arm in Embodiment 1 of the present invention;

[0032] Figure 4 This is a schematic diagram of the structure of the rear continuum stack unit in Embodiment 1 of the present invention;

[0033] Figure 5 This is a schematic diagram of the front-end continuum stacked unit in Embodiment 1 of the present invention;

[0034] Figure 6 This is a schematic diagram of the moving parts of the rigid dual drive mechanism in Embodiment 1 of the present invention. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments to provide a clearer understanding of its objectives, features, and advantages. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the invention, but are merely illustrative of the essential spirit of the invention's technical solution.

[0036] like Figure 1 As shown, the present invention provides a rigid-flexible dual-driven snake-like surgical robot, comprising: a rigid dual-driven mechanism 1, a rear flexible continuum mechanism 2, a tendon constraint structure 3, and a front flexible continuum mechanism 4; the rear flexible continuum mechanism 2 and the front flexible continuum mechanism 4 are associated by tendon length to form a dual continuum mechanism; the rigid dual-driven mechanism 1 is associated with the end face motion of the rear flexible continuum mechanism 2, and the rigid dual-driven mechanism 1 can drive the rear flexible continuum mechanism 2 to bend, rotate, and extend in any direction, thereby coupling and driving the front flexible continuum mechanism 4 to bend, rotate, and extend in any direction.

[0037] In this embodiment, as Figure 2 As shown, the rigid dual drive mechanism 1 includes: a base 11, a moving component 13, and three sets of parallel rotating components 12; the rotating components 12 include: a bottom centripetal swing rod 121, a bottom middle connecting rod 122, a top middle connecting rod 123, and a top centripetal swing rod 124; the moving component 13 includes: a moving base 131 and a pressure plate 132.

[0038] The base 11 and the moving component 13 are respectively constrained by through-hole hinges with the bottom centripetal swing arm 121 and the top centripetal swing arm 124; the bottom centripetal swing arm 121 is constrained by through-hole hinge with the bottom middle connecting rod 122; the top centripetal swing arm 124 is constrained by through-hole hinge with the top middle connecting rod 123; the bottom middle connecting rod 122 is constrained by through-hole hinge with the top middle connecting rod 123; and the moving base 131 and the pressure plate 132 are fixedly connected.

[0039] In the rotating assembly 12, the hinge axis of the bottom radial swing rod 121 intersects the base 11 and the hinge axis of the bottom connecting rod 122 at the rotation center of the base 11. The hinge axis of the top radial swing rod 124 intersects the moving part 13 and the hinge axis of the top connecting rod 123 at the rotation center of the moving part 13. The rotating assemblies 12 in the rigid dual drive mechanism 1 have identical structures. The angle between the two hinge axes of the bottom radial swing rod 121 is equal to the angle between the two hinge axes of the top radial swing rod. The spatial positional relationship between the two hinge axes of the bottom connecting rod 122 and the two hinge axes of the top connecting rod 123 is the same.

[0040] In this embodiment, the bottom centripetal swing rod 121, the bottom middle connecting rod 122, the top middle connecting rod 123, and the top centripetal swing rod 124 are all designed as mechanical components with a certain mechanical strength. Their shapes are not limited. For example, they can be rod-shaped, plate-shaped, or other shapes or combinations of multiple shapes.

[0041] In this embodiment, preferably, the base 11 is designed with three sets of fixing holes to fix the power source to it; at the same time, the bottom of the bottom radial rocker arm 121 is designed as an externally protruding gear to transmit the input power to the mechanism through gear transmission.

[0042] In this embodiment, as Figure 6 As shown, preferably, the upper surface of the motion base 131 is provided with tendon guide grooves and tendon holes, and the tendon guide grooves and tendon holes correspond one-to-one. After the tendon passes through the corresponding guide grooves and holes, it is pressed tightly by the fixed connection between the motion base 131 and the pressure plate 132.

[0043] In this embodiment, as Figure 3 As shown, the rear flexible continuum mechanism 2 includes: a top fixing member 22, a bottom fixing member 23, a rear continuum lamination unit 21, and a rear tendon 20; the rear continuum lamination unit 21 includes a rear planar lamination 211 and a plurality of rear C-shaped laminations 212.

[0044] The structure of the rear continuum stack unit 21 is as follows: Figure 4 As shown, the rear C-shaped laminate 212 is shaped like the letter "C" and is manufactured by bending process. It has several tendon constraint holes, and the bent part serves as an elastic structure of a continuous body.

[0045] The top fixing member 22 is connected in series with a number of rear end tendons 20, a number of rear end continuous stacked units 21, and the bottom fixing member 23, and the tendons are fixedly connected to the top fixing member 22.

[0046] In this embodiment, as Figure 3 As shown, the tendon constraint structure 3 includes a bending constraint structure 31 and an extension constraint structure 32; the bending constraint structure 31 includes a bending constraint inner core 311, a first bending constraint outer shell 312 and a second bending constraint outer shell 313; the extension constraint structure 32 includes an extension constraint inner core 321 and an extension constraint outer shell 322.

[0047] The bending constraint structure 31 realizes the constraint and guidance functions of the tendon. The tendon guide groove is opened on the inner surface of the first bending constraint shell 312 and the second bending constraint shell 313. The bending constraint inner core 311 is pressed with the two to realize the constraint of the tendon.

[0048] Wherein, the bending constraint inner core 311 and the first bending constraint outer shell 312 are fixedly connected; the bending constraint inner core 311 and the second bending constraint outer shell 313 are fixedly connected; the extension constraint inner core 321 and the extension constraint outer shell 322 are fixedly connected; and the second bending constraint outer shell 313 and the extension constraint outer shell 322 are fixedly connected.

[0049] In this embodiment, both the bending constraint structure 31 and the extension constraint structure 32 are designed as mechanical components with a certain mechanical strength, and the bending angle of the bending constraint structure 31 and the extension depth of the extension constraint structure 32 are not limited.

[0050] In this embodiment, preferably, tendon guide grooves are designed on the inner walls of the base 11, the first bending constraint shell 312 and the second bending constraint shell 313 to facilitate the processing of the guide grooves using additive manufacturing.

[0051] In this embodiment, as Figure 3 As shown, the front flexible continuum mechanism 4 includes: an end fixing member 42, a front continuum lamination unit 41, and a front tendon 40; the front continuum lamination unit 41 includes a front planar lamination 411 and a plurality of front C-shaped laminations 412.

[0052] The structure of the front-end continuous laminate unit 41 is as follows: Figure 5 As shown, the front C-shaped lamination 412 is shaped like the letter "C" and is manufactured by bending process. It has several tendon constraint holes, and the bent part serves as an elastic structure of a continuous body. The front planar lamination 411 has several holes inside, which serve as surgical instrument channels.

[0053] The end fixation member 42 is connected in series with several front continuous stacked units 41 through several front tendons 40, and the front tendons 40 are fixedly connected to the end fixation member 42.

[0054] In this embodiment, the number of tendons and the included angle between each tendon are exactly the same in the rear flexible continuum mechanism 2 and the front flexible continuum mechanism 4, and the rear tendon 20 and the front tendon 40 are the same number of tendons.

[0055] The motion base 131 is fixedly connected to the top fixing member 22; the base 11 is fixedly connected to the bottom fixing member 23; the base 11 is fixedly connected to the bending constraint inner core 311; the tendon hole structure at the connection point of the motion member 13, the rear flexible continuum mechanism 2 and the tendon constraint structure 3 is completely identical; the tendon hole structure at the connection point of the front continuum stack unit 41 and the extended constraint inner core 321 is completely identical.

[0056] In this embodiment, preferably, several surgical instrument channels are provided in the tendon constraint structure 3 and the front flexible continuum mechanism 4, so that the required surgical instruments can reach the operating end of the robotic arm through the channels to meet the surgical operation requirements of the flexible continuum robotic arm; wherein, the surgical instrument channels of the tendon constraint structure 3 are located at the tendon gap at the maximum diameter position of the bending constraint structure 31.

[0057] In this embodiment, preferably, the lamination radius of the rear flexible continuum mechanism 2 is designed to be larger than that of the front flexible continuum mechanism 4, so that when the length changes of the tendons at the front and rear ends are the same, the bending radius of the front end is larger, thereby improving the flexibility of the front end continuum.

[0058] Those skilled in the art can readily make various changes and modifications based on the provided textual description, drawings, and claims, without departing from the spirit and scope of the invention as defined by the claims. Any modifications or equivalent variations made to the above embodiments based on the technical concept and essence of the invention fall within the protection scope defined by the claims of this invention.

Claims

1. A rigid-flexible dual actuated snake-like surgical robot, characterized by, Comprise: rigid dual driving mechanism, rear end flexible continuum mechanism, tendon constraint structure and front end flexible continuum mechanism; the rear end flexible continuum mechanism and the front end flexible continuum mechanism are internally constrained by laminated units, and the lengths of the tendons are associated to form dual continuum mechanisms; the tendon constraint structure is used for the constraint and guidance of the tendons between the rear end flexible continuum mechanism and the front end flexible continuum mechanism, and a plurality of surgical instrument channels are further arranged, which reach the end of the front end flexible continuum mechanism from the tendon constraint mechanism; the rigid dual driving mechanism is movably associated with the end surface of the rear end flexible continuum mechanism, and the rear end flexible continuum mechanism is driven to bend, rotate and stretch in any direction by the rigid dual driving mechanism, so as to drive the front end flexible continuum mechanism to bend, rotate and stretch in any direction; the rigid dual driving mechanism comprises a base, a moving part and at least three groups of parallel rotating assemblies; the rotating assembly comprises a bottom centripetal swing rod, a bottom middle connecting rod, a top middle connecting rod and a top centripetal swing rod; wherein the base and the moving part are respectively hingedly constrained with the bottom centripetal swing rod and the top centripetal swing rod using through-hole hinges; the bottom centripetal swing rod is hingedly constrained with the bottom middle connecting rod using a through-hole hinge; the top centripetal swing rod is hingedly constrained with the top middle connecting rod using a through-hole hinge; and the bottom middle connecting rod is hingedly constrained with the top middle connecting rod using a through-hole hinge.

2. A rigid-flexible dual actuation snake-like surgical robot according to claim 1, characterized in that, the hinging shaft axes of the bottom centripetal swing rod and the bottom middle connecting rod in the rotating assembly always intersect at the rotation center of the base, and the hinging shaft axes of the top centripetal swing rod and the top middle connecting rod in the rotating assembly always intersect at the rotation center of the moving part; each group of rotating assemblies in the rigid dual driving mechanism is completely identical; the included angle between the two hinging shaft axes of the bottom centripetal swing rod is equal to the included angle between the two hinging shaft axes of the top centripetal swing rod, and the spatial positional relationship of the two hinging shaft axes of the bottom middle connecting rod and the two hinging shaft axes of the top middle connecting rod is the same.

3. The rigid-flexible dual actuation snake-like surgical robot according to claim 1, wherein, the moving part comprises a moving base and a pressing plate fixedly connected, and the upper surface of the moving base is provided with tendon guide grooves and tendon hole positions which are one-to-one corresponding; after the tendons pass through the corresponding guide grooves and hole positions, the tendons are compressed due to the fixed connection between the moving base and the pressing plate.

4. A rigid-flexible dual actuation snake-like surgical robot according to claim 3, wherein, the rear end flexible continuum mechanism comprises a top fixing part, a bottom fixing part, a plurality of rear end continuum laminated units and rear end tendons; each rear end continuum laminated unit comprises a rear end plane laminated unit and a plurality of rear end C-shaped laminated units; the rear end C-shaped laminated units are installed on the rear end plane laminated unit, the rear end plane laminated unit is provided with a plurality of tendon constraint hole positions, the rear end C-shaped laminated units are in the shape of the letter C and are manufactured by bending process, and a plurality of tendon constraint hole positions are provided on the rear end C-shaped laminated units corresponding to the rear end plane laminated unit, and the bent part serves as an elastic structure of the continuum; The top fixing member is connected in series with the rear end continuum laminated units and the bottom fixing member through the rear end tendons, and the tendons are fixedly connected with the top fixing member; the moving base is fixedly connected with the top fixing member; and the base is fixedly connected with the bottom fixing member.

5. The rigid-flexible dual actuation snake-like surgical robot according to claim 1, wherein, The front end flexible continuum mechanism comprises a terminal fixing member, a plurality of front end continuum laminated units and front end tendons. The front end continuum laminated unit comprises a front end plane laminated sheet and a plurality of front end C-shaped laminated sheets. Each front end continuum laminated unit comprises a front end plane laminated sheet and a plurality of front end C-shaped laminated sheets; the front end C-shaped laminated sheets are installed on the front end plane laminated sheet, the front end plane laminated sheet is provided with a plurality of tendon constraint hole positions, the front end C-shaped laminated sheets are in the shape of the letter C and are manufactured through a bending process, and a plurality of tendon constraint hole positions are arranged on the front end C-shaped laminated sheets and correspond to the front end plane laminated sheet; and the bent part serves as an elastic structure of the continuum. The terminal fixing member is connected in series with the front end continuum laminated units through the front end tendons, and the front end tendons are fixedly connected with the terminal fixing member.

6. The rigid-flexible dual actuation snake-like surgical robot according to claim 1, wherein, The tendon constraint structure comprises a bending constraint structure and an elongation constraint structure. The bending constraint structure comprises a bending constraint inner core, a first bending constraint outer shell and a second bending constraint outer shell; and the elongation constraint structure comprises an elongation constraint inner core and an elongation constraint outer shell. The bending constraint inner core is fixedly connected with the first bending constraint outer shell; the elongation constraint inner core is fixedly connected with the elongation constraint outer shell; the second bending constraint outer shell is fixedly connected with the elongation constraint outer shell; and the bending constraint inner core is fixedly connected with the base.

7. A rigid-flexible dual actuation snake-like surgical robot according to claim 6, wherein, The cross-sectional diameter of the bending constraint structure along the bending direction is the smallest at the two end faces and gradually increases in the middle part; the tendon spacing is the largest at the position of the maximum cross-sectional radius, so that a surgical instrument channel is formed therein.

8. The rigid-flexible dual actuation snake-like surgical robot according to claim 1, wherein, The number of tendons and the included angle between the tendons in the rear end flexible continuum mechanism and the front end flexible continuum mechanism are completely the same, and the tendons in the two mechanisms are the same tendons.

9. The rigid-flexible dual actuation snake-like surgical robot according to claim 1, wherein, The radius of the rear end flexible continuum mechanism is greater than the radius of the front end flexible continuum mechanism, so that when the length of the front and rear tendons changes, the bending radius of the front end is greater.

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