A mechanism for locking and unlocking a wire-driven variable stiffness continuum robot

Abstract

The application provides a mechanism for locking and unlocking a wire-driven variable stiffness continuum robot, comprising a self-locking wire wheel module, a splicable shell module, a servo transmission module, a linear drive module and a support module, wherein the splicable shell module is connected and fixed with the support module; the linear drive module is installed on the support module, the servo transmission module is installed on the linear drive module, the linear drive module can drive the servo transmission module to move forward and backward, the self-locking wire wheel module is installed on the splicable shell module, and the servo transmission module can complete unlocking or locking after being connected with the self-locking wire wheel module. The mechanism for locking and unlocking the wire-driven variable stiffness continuum robot has the advantages of good expandability, simple disassembly, simple control mode, self-locking performance and the ability to control the locking of more joints with a small number of servos.

Description

TECHNICAL FIELD

[0001] The present application relates to medical devices, in particular to a mechanism for locking and unlocking a wire-driven variable stiffness continuum robot. BACKGROUND

[0002] Existing medical surgical robots are mainly divided into rigid surgical robots and flexible surgical robots. The rigid surgical robot is more traditional, widely used, easy to control and accurate in operation, but it is difficult to bypass the tortuous human tissue to reach the lesion, and it is easy to contact and damage sensitive organs and tissues such as organs and blood vessels. The flexible surgical robot is relatively more flexible and soft. Common flexible surgical robots mainly include concentric tube robots and wire-controlled continuum robots, etc. The wire-controlled continuum robot is generally composed of multiple joints connected together, and the movement and turning thereof are controlled by using a wire rope penetrating therein. If the wire-controlled continuum robot has too high stiffness, it is easy to damage the surrounding tissues and organs, and if the wire-controlled continuum robot has too low stiffness, it is easy to twist and lose accuracy.

[0003] Due to the difficulty of setting the stiffness of the wire-controlled continuum robot to adapt to various medical scenes, the variable stiffness surgical robot has become a research hotspot in the field of surgical robots. The wire-driven variable stiffness continuum robot is one of them. The operator can stretch the wire rope for locking the joints at a specific length, so as to drive the locking structure built-in the robot to achieve the purpose of locking the joints. The wire-driven variable stiffness continuum robot needs a shorter time to unlock or lock a specific joint. When it is necessary to expand the activity range of the robot, increase the force applied at the end, and increase the accuracy, the robot stiffness can be quickly increased by locking part of the joints. When it is necessary to reduce the contact force between the robot and the environment, the stiffness of the robot can be quickly reduced by unlocking part of the joints. For the locking and unlocking of such wire-driven variable stiffness continuum robots, a steering device fixed at the operating end is generally used. The wire rope for driving the locking mechanism is fixed on the rotating shaft (disc) of the steering device. When it is necessary to lock a specific joint, the corresponding steering device is directly driven to stretch the corresponding wire rope, drive the locking mechanism inside the joint or between the joints to achieve the required shape when locking, and complete the locking of the corresponding joint. Similarly, when it is necessary to unlock a specific joint, the corresponding steering device is directly driven to stretch the corresponding wire rope, drive the locking mechanism inside the joint or between the joints to achieve the required shape when unlocking, and complete the unlocking of the joint.

[0004] When operating the movement of the wire-driven variable stiffness continuum robot, only a few steering devices or a few motors (such as CN111956328B) are generally needed to directly drive the wire rope built-in the continuum robot for controlling the movement direction (there are also special patents using a few ball screws with wire ropes to directly stretch the wire rope, such as CN113305806A). The number of wire ropes for controlling the movement of the robot is generally not too much. Generally, each driving mechanism (such as a steering device, a motor, or a screw) only drives one wire rope.

[0005] However, the existing mechanism for locking and unlocking the wire-driven variable stiffness continuum robot generally also places several connecting locking devices of the steering wheel or motor or lead screw in a position suitable for operating the robot locking (generally located at the rear end of the robot fixed point). For the wire-driven variable stiffness continuum robot using wire ropes to lock and unlock the joints, each joint can be locked individually, a locking mechanism needs two wire ropes connection, one for locking, one for unlocking, so a wire-driven variable stiffness continuum robot using wire ropes to lock and unlock the joints if it is composed of n joints, it needs 2n wire ropes to control its locking mechanism, it needs 2n (or n, because for part of the locking mechanism, a steering wheel or motor can control the two wire ropes responsible for locking and unlocking on a locking mechanism by forward and reverse rotation) steering wheel or motor or lead screw device, when the number of robot joints is large (such as more than 30), it will greatly increase the difficulty of installing the control locking mechanism, the space required for installing the device, the difficulty of controlling the locking device, the economic cost of purchasing equipment… At the same time, if you want to add several joints to the front end of the original robot, you can only find ways to add more steering wheels or motors or lead screws at the rear end of the mechanism when using traditional locking mechanisms, which has poor expandability. SUMMARY

[0006] In view of the above defects of the traditional mechanism for controlling the locking of the wire-driven variable stiffness continuum robot, a new type of splicing type mechanism for locking and unlocking the wire-driven variable stiffness continuum robot is proposed, which only needs to add a small number of modules of the new type of mechanism when expanding the number of robot joints. The mechanism is simple to disassemble, simple to control, has self-locking performance, can control the locking of more joints with a small number of steering wheels, the length of the stretched wire rope is quantitative each time, but the locking speed is relatively slow compared with the traditional operation mode.

[0007] The application provides a mechanism for locking and unlocking a wire-driven variable stiffness continuum robot, comprising a self-locking wire wheel module, a splicing type shell module, a steering wheel transmission module, a linear drive module and a support module, wherein the splicing type shell module is connected and fixed with the support module; the linear drive module is installed on the support module, the steering wheel transmission module is installed on the linear drive module, the linear drive module can drive the steering wheel transmission module to move forward and backward, the self-locking wire wheel module is installed on the splicing type shell module, and the steering wheel transmission module can complete unlocking or locking after being connected with the self-locking wire wheel module.

[0008] As a further improvement of the present application, the support module comprises a first support plate, a second support plate, a motor, a screw rod and an optical shaft, wherein the two ends of the optical shaft are connected with the first support plate and the second support plate respectively, the two ends of the screw rod are connected with the first support plate and the second support plate respectively, the motor is connected with the screw rod, and the linear drive module is installed on the screw rod.

[0009] As a further improvement of the present application, the support module further comprises a bottom plate, a third support plate, an inclined pulley and a taper plate for winding, the first support plate, the second support plate and the third support plate are respectively installed on the bottom plate, the first support plate, the second support plate and the third support plate are parallel, the inclined pulley is installed on the second support plate, and the taper plate is installed on the third support plate.

[0010] As a further improvement of the present application, the linear drive module comprises a linear drive module mounting seat, a screw rod nut is arranged on the linear drive module mounting seat, the screw rod nut is installed on the screw rod, an optical shaft hole is arranged on the linear drive module mounting seat, and the optical shaft passes through the optical shaft hole.

[0011] As a further improvement of the present application, the steering gear transmission module comprises a steering gear support, a steering gear, a steering gear arm and a steering gear end gear, the steering gear is installed on the steering gear support, the steering gear is connected with the steering gear arm, and the steering gear arm is connected with the steering gear end gear.

[0012] As a further improvement of the present application, the steering gear end gear is a non-full tooth gear, one part is a toothed part, and the other part is a toothless part.

[0013] As a further improvement of the present application, when the linear drive module drives the steering gear transmission module to move axially, the toothless part of the steering gear end gear faces outward, and the toothed part faces inward, so as to avoid collision.

[0014] As a further improvement of the present application, the self-locking wire wheel module comprises a self-locking end gear, a worm gear mechanism, a wire wheel and a wire rope, the self-locking end gear is fixed on the screw rod of the worm gear mechanism, the wire wheel is fixed on the worm wheel of the worm gear mechanism, and the wire rope is installed on the wire wheel.

[0015] As a further improvement of the present application, the self-locking end gears located on different self-locking wire wheel modules are staggered.

[0016] As a further improvement of the application, the docking process of the steering gear transmission module and the self-locking wire wheel module is that the linear drive module drives the steering gear transmission module to move forward and backward, so that the steering gear end gear of the steering gear transmission module is engaged with the self-locking end gear of the self-locking wire wheel module, realizing the docking of the steering gear transmission module and the self-locking wire wheel module; the locking and unlocking process of the wire-driven variable stiffness continuum robot is that the steering gear drives the steering gear arm to rotate, the steering gear arm drives the steering gear end gear to rotate, the steering gear end gear drives the self-locking end gear to rotate, the self-locking end gear drives the wire wheel to rotate through the worm gear mechanism, and the wire wheel rotation pulls the wire rope, realizing the locking and unlocking of the wire-driven variable stiffness continuum robot.

[0017] As a further improvement of the application, the self-locking wire wheel module further comprises a straight pulley, and the wire rope is tensioned on the straight pulley.

[0018] As a further improvement of the application, the splicable shell module comprises an arc-shaped splicing shell and a head-tail splicing bottom plate, the arc-shaped splicing shell is connected with the head-tail splicing bottom plate, one end of the arc-shaped splicing shell away from the head-tail splicing bottom plate is provided with a head-tail splicing convex tooth, and the bottom surface of the head-tail splicing bottom plate is provided with a head-tail splicing groove; when splicing the head and tail, the head-tail splicing convex tooth of the arc-shaped splicing shell of the rear splicable shell module is connected with the head-tail splicing groove of the head-tail splicing bottom plate of the front splicable shell module, and when circumferential splicing, the arc-shaped splicing shells of two or more splicable shell modules are spliced into a segmented circle or arc.

[0019] As a further improvement of the application, two or more self-locking wire wheel modules are installed on one splicable shell module, the worm gear mechanism of one self-locking wire wheel module drives a group of wire wheels, and one group of wire wheels realizes the locking and unlocking of one joint, so that the locking and unlocking of multiple joints can be realized, and a small number of steering gears can be used to control the locking of more joints.

[0020] As a further improvement of the application, one splicable shell module and the self-locking wire wheel modules thereon constitute a control sub-module, two or more control sub-modules constitute a control module, and one linear drive module and the steering gear transmission module thereon constitute a drive module; one drive module can correspond to one control module or multiple control modules, and a small number of steering gears can be used to control the locking of more joints.

[0021] The application has the advantages that the linear drive module drives the steering gear transmission module to move forward and backward, the steering gear transmission module completes unlocking or locking after being docked with the self-locking wire wheel module, has good expandability, is simple to disassemble, has simple control mode, has self-locking performance, and a small number of steering gears can be used to control the locking of more joints. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other solutions can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the overall structure of a locking and unlocking line-driven variable stiffness continuum robot according to the present invention (with three sets of control modules installed, which can control the locking or unlocking of 30 joints).

[0024] Figure 2 This is a schematic diagram of the overall structure of a locking and unlocking line-driven variable stiffness continuum robot according to the present invention (with half of the control module installed, which can control the locking or unlocking of 5 joints).

[0025] Figure 3 This is a schematic diagram of the support module of a mechanism for locking and unlocking line-driven variable stiffness continuum robot according to the present invention.

[0026] Figure 4 This is a structural diagram of the connectable shell module and self-locking wheel module of the mechanism for locking and unlocking line-driven variable stiffness continuum robot of the present invention.

[0027] Figure 5 This is a structural schematic diagram from another perspective of the connectable shell module and self-locking wheel module of the mechanism for locking and unlocking line-driven variable stiffness continuum robot of the present invention.

[0028] Figure 6 This is a schematic diagram of the structure of the self-locking end gears on the self-locking wheel module of the mechanism for locking and unlocking a variable stiffness continuum robot of the present invention, which are staggered.

[0029] Figure 7 This is a schematic diagram of the linear drive module (with two servo motor transmission modules fixed on it) of the mechanism for locking and unlocking a variable stiffness continuum robot driven by a locking and unlocking line according to the present invention.

[0030] Figure 8 This is a schematic diagram of the linear drive module of a locking and unlocking line-driven variable stiffness continuum robot according to another perspective of the present invention.

[0031] Figure 9 This is a schematic diagram of the servo end gear of a locking and unlocking line-driven variable stiffness continuum robot according to the present invention, with the toothless part facing outward and the toothed part facing inward.

[0032] Figure 10 is a perspective view of a half-group operation system of a mechanism for locking and unlocking a wire-driven variable-stiffness continuum robot according to the present application.

[0033] Figure 11 is a plan view of a half-group operation system of a mechanism for locking and unlocking a wire-driven variable-stiffness continuum robot according to the present application.

[0034] Figure 12 is a perspective view of a three-group operation system of a mechanism for locking and unlocking a wire-driven variable-stiffness continuum robot according to the present application.

[0035] Figure 13 is a schematic view of a second support plate of a mechanism for locking and unlocking a wire-driven variable-stiffness continuum robot according to the present application.

[0036] Figure 14 is a schematic view of a third support plate of a mechanism for locking and unlocking a wire-driven variable-stiffness continuum robot according to the present application. DETAILED DESCRIPTION

[0037] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0038] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the scope of protection of the present application. In addition, the terms "first", "second" and the like are only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by "first", "second" and the like can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0039] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood through specific circumstances.

[0040] The application is further described below in conjunction with the accompanying drawings and specific embodiments.

[0041] As shown in the drawings and specific embodiments, Figure 1 The locking and unlocking wire-driven variable stiffness continuum robot mechanism includes a self-locking wire wheel module 5, a splicable shell module 2, a steering gear transmission module 4, a linear drive module 3, and a support module 1.

[0042] The self-locking wire wheel module 5 is installed on the splicable shell module 2, and can rotate 360 degrees, be easily disassembled and self-locked; the splicable shell module 2 is connected and fixed with the support module 1; the linear drive module 3 drives the steering gear transmission module 4 to move forward and backward, and the steering gear transmission module 4 completes unlocking or locking after connecting the self-locking wire wheel module 5.

[0043] As shown in the drawings and specific embodiments, Figure 1 The locking and unlocking wire-driven variable stiffness continuum robot mechanism can install three groups of control modules, and can control 30 joint locking or unlocking, one group of control modules including two self-locking wire wheel modules 5 and two splicable shell modules 2, which can be matched with multiple control modules through one linear drive module 3 and steering gear transmission module 4.

[0044] As shown in the drawings and specific embodiments, Figure 2 The locking and unlocking wire-driven variable stiffness continuum robot mechanism can install half a group of control modules, and can control 5 joint locking or unlocking.

[0045] As shown in the drawings and specific embodiments, Figure 3 The specific structure of the support module 1 is further described.

[0046] The support module 1 is used to support all devices, drive the linear drive module 3 with a lead screw, fix the splicable shell module 2, and store the wire rope.

[0047] The support module 1 includes a first support plate 12, a second support plate 13, a motor 19, a lead screw 15, and an optical shaft 16, wherein the two ends of the optical shaft 16 are connected with the first support plate 12 and the second support plate 13 respectively, the two ends of the lead screw 15 are connected with the first support plate 12 and the second support plate 13 respectively, the motor 19 is connected with the lead screw 15 through a shaft coupling 111, the linear drive module 3 is installed on the lead screw 15, the linear drive module 3 can be driven to move forward and backward by the motor 19 driving the lead screw 15, and the optical shaft 16 can guide the linear drive module 3 when moving.

[0048] The support module 1 further comprises a bottom plate 11, a third support plate 14, an inclined pulley 17 and a taper plate 18 for winding the wire, the first support plate 12, the second support plate 13 and the third support plate 14 are respectively installed on the bottom plate 11, the first support plate 12, the second support plate 13 and the third support plate 14 are parallel to each other, the inclined pulley 17 is installed on the second support plate 13, and the taper plate 18 is installed on the third support plate 14.

[0049] The motor 19 is preferably a servo motor.

[0050] The first support plate 12 is provided with a first lead screw support seat 112, the second support plate 13 is provided with a second lead screw support seat 113, and the two ends of the lead screw 15 are respectively installed on the first lead screw support seat 112 and the second lead screw support seat 113.

[0051] The motor 19 is installed on the motor support 110.

[0052] Six optical shafts 16 are fixed between the first support plate 12 and the second support plate 13, and a ball screw 15 is fixed between the first support plate 12 and the second support plate 13 for driving the linear drive module 3, and the motor 19 is used for driving. Figure 13 As shown in the figure, the two square holes 131 above are used to prevent the lower wire from being blocked), all the wires connected by the operation module are received by the ten inclined pulleys 17 on the second support plate 13 and then enter the two holes 141 on the third support plate 14 (as shown in the figure), and finally are uniformly induced into the hole at the tail of the third support plate 14, which can be connected to the continuum robot. Figure 14

[0053] As shown in the figure, Figure 7 , 8 Further explanation of the specific structure of the linear drive module is given.

[0054] The linear drive module 3 comprises a linear drive module mounting seat 31, the linear drive module mounting seat 31 is provided with a lead screw nut 32, the lead screw nut 32 is installed on the lead screw 15, the linear drive module mounting seat 31 is provided with an optical shaft hole 33, and the optical shaft 16 passes through the optical shaft hole 33.

[0055] The linear drive module mounting seat 31 can be driven by the lead screw 15 to move axially forward and backward, and the rudder transmission module 4 is driven to move synchronously by the linear drive module mounting seat 31.

[0056] The lead screw 15 is preferably a ball screw.

[0057] As shown in the figure, Figure 7 , 8 ​As shown, the specific structure of the servo drive module 4 will be further explained.

[0058] The servo drive module 4 includes a servo bracket 44, a servo 41, a servo arm 42, and a servo end gear 43. The servo 41 is mounted on the servo bracket 44, the servo 41 is connected to the servo arm 42, and the servo arm 42 is connected to the servo end gear 43.

[0059] The servo arm 42 can be rotated by the servo motor 41, which in turn drives the gear 43 at the servo end to rotate, providing driving force for locking and unlocking the self-locking reel module 5.

[0060] The servo end gear 43 is a non-full-tooth gear, consisting of a toothed portion 431 and a toothless portion 432.

[0061] like Figure 9 As shown, when the linear drive module 3 drives the servo transmission module 4 to move axially, the toothless part 432 of the servo end gear 43 faces outward and the toothed part 431 faces inward to avoid collision.

[0062] The linear drive module 3 is not fixed on the optical axis 16, but can move axially on the optical axis 16. It is driven by the lead screw 15. Two servo motors 41 are fixed on one linear drive module 3. A servo motor end gear 43 is fixed on the servo motor arm 42. The servo motor end gear 43 is a non-full gear (the non-full gear is to prevent collision with the self-locking end gear 51 when the linear drive module 3 moves axially). One linear drive module 3 corresponds to a set of operation modules. The servo motor end gear 43 moves in the internal space of the arc-shaped spliced ​​shell 21. When it is necessary to drive the corresponding reel 53, it directly drives the corresponding servo motor 41. The servo motor end gear 43 rotates one revolution (or other number of revolutions), which drives the reel 53 to rotate a fixed number of revolutions, so that the length of the corresponding rope is shortened by a fixed distance.

[0063] like Figure 4 , 5 As shown, the self-locking reel module 5 is mounted on the modular housing module 2.

[0064] The self-locking reel module 5 includes a self-locking end gear 51, a worm gear mechanism 52, a reel 53, and a line. The self-locking end gear 51 is fixed on the screw 521 of the worm gear mechanism 52, the reel 53 is fixed on the worm gear 522 of the worm gear mechanism 52, and the line is mounted on the reel 53.

[0065] When the worm gear is the driving element, and the lead angle of the worm gear mechanism is less than the friction angle, the mechanism will exhibit a self-locking phenomenon.

[0066] The rudder transmission module 4 can be driven by the linear drive module 3 to move forward and backward to dock with the self-locking wire wheel module 5, that is, the rudder end gear 43 is engaged with the self-locking end gear 51. The rudder arm 42 is driven to rotate by the rudder 41, the rudder arm 42 drives the rudder end gear 43 to rotate, the rudder end gear 43 drives the self-locking end gear 51 to rotate, the self-locking end gear 51 drives the wire wheel 53 to rotate through the worm gear mechanism 52, and the wire wheel 53 controls the tension or relaxation of the wire rope, so as to realize the locking and unlocking of the wire-driven variable stiffness continuum robot.

[0067] As shown in Figure 6 , the self-locking end gears on different self-locking wire wheel modules are staggered.

[0068] The docking process of the rudder transmission module 4 and the self-locking wire wheel module 5 is that the linear drive module 3 drives the rudder transmission module 4 to move forward and backward, so that the rudder end gear 43 of the rudder transmission module 4 is engaged with the self-locking end gear 51 of the self-locking wire wheel module 5, and the docking of the rudder transmission module 4 and the self-locking wire wheel module 5 is realized.

[0069] The locking and unlocking process of the wire-driven variable stiffness continuum robot is that the rudder arm 42 is driven to rotate by the rudder 41, the rudder arm 42 drives the rudder end gear 43 to rotate, the rudder end gear 43 drives the self-locking end gear 51 to rotate, the self-locking end gear 51 drives the wire wheel 53 to rotate through the worm gear mechanism 52, and the wire wheel 53 is pulled to rotate to realize the locking and unlocking of the wire-driven variable stiffness continuum robot.

[0070] As shown in Figure 4 , the self-locking wire wheel module 5 further comprises a straight pulley 54, and the wire rope is tensioned on the straight pulley 54.

[0071] As shown in Figure 4 , 5 , the splicable shell module 2 comprises an arc-shaped splicing shell 21 and a head-tail splicing bottom plate 22, the arc-shaped splicing shell 21 is connected with the head-tail splicing bottom plate 22, one end of the arc-shaped splicing shell 21 away from the head-tail splicing bottom plate 22 is provided with a head-tail splicing convex tooth 211, and the bottom surface of the head-tail splicing bottom plate 22 is provided with a head-tail splicing concave groove 221; when splicing, the head-tail splicing convex tooth 211 of the arc-shaped splicing shell 21 of the rear splicable shell module 2 is connected with the head-tail splicing concave groove 221 of the front splicable shell module 2, and when circumferential splicing, the arc-shaped splicing shells 21 of two or more splicable shell modules 2 are spliced into a segmented circle or arc, that is, two semicircles or multiple sectors after a circle is divided in the middle.

[0072] The screw rod 521 of the worm gear mechanism 52 is installed on the spliced bottom plate 22 through a bearing 55.

[0073] The tail spliced bottom plate 22 is provided with an optical axis hole 222 for the passage of the optical axis 16.

[0074] The arc-shaped spliced shell 21 of the two splicable shell modules 2 is preferably spliced into a segmented circle or arc, that is, a group of operation modules. Three or four or more can also be spliced into a segmented circle or arc, that is, a group of operation modules.

[0075] As shown in Figure 4 , 5 , the self-locking wire wheel module 5 and the splicable shell module 2 shown in the figure are generally referred to as “half a group of operation modules” in the text, and two operation modules placed radially symmetrically are referred to as “a group of operation modules”. Half a group of operation modules contains 5 groups of self-locking wire wheel modules 5 (one worm 521 + one worm gear 522 is a group, the self-locking end gear 51 on each worm 521 is of different heights, as shown in Figure 6 ) and 1 group of splicable shell modules 2.

[0076] The self-locking end gear 51 is preferably a pinion, and the steering gear end gear 43 is preferably a large gear.

[0077] In the self-locking wire wheel module, the self-locking end gear 51 on the worm 521 is integrated with the worm 521, and the steering gear end gear 43 in the linear drive module 3 will drive the self-locking end gear 51 to rotate and thus drive the worm 521 to rotate; the worm gear 521 is innovatively improved, and the two sides thereof are wire wheels 53 with screw holes (the wire wheels 53 and the worm gear 522 are integrally formed by POM machining or metal machining), the rotation of the worm 521 drives the rotation of the two wire wheels 53 on the worm gear 522, thereby driving the wire rope to lock or unlock the robot joint.

[0078] The basic structure of the splicable shell module 2 is made of 3D printing, and the lower end of each worm gear 522 has a straight pulley 54 to support the wire rope on the wire wheel 53, and a large through hole 24 is left for the extension of the steering gear wire (the steering gear wire is collected at the operation end, and an extension line is used when it is not long enough). The splicable shell module 2 can be spliced end to end (axially), and can be continuously expanded (after the last splicable shell module 2 is spliced, an additional bottom plate 22 in the splicable shell module 2 is needed to provide a bearing for the worm 521.

[0079] The mechanism for locking and unlocking the wire-driven variable stiffness continuum robot provided by the application has the specific working principle as follows:

[0080] As shown in Figures 10 to 11 , the simplest system is first described by example (half a group of operation modules).

[0081] At this time, the operation module has been assembled and fixed on the optical axis 16 by the top screw 23, and cannot move relative to the optical axis 16; the linear drive module 3 has been assembled and is in the default state (the toothed part 431 of the steering gear end gear 43 faces the screw nut 32), and the steering gear end gear 43 is aligned with the self-locking end gear 51 of No. A1, see Figure 11 .

[0082] As shown in Figure 11 , at this time, it is assumed that the continuum robot to be controlled has 5 joints, and each joint is in the unlocked state, the No. B1 joint is driven by the self-locking end gear 51 of No. A1 and the wire wheel 53, and two wire ropes (referred to as A and B wire ropes) are screwed on the wire wheel bolt 53 (when the joint is in the locked state, the A wire rope is pulled tight, and the B wire rope is relaxed; when the joint is in the unlocked state, the A wire rope is relaxed, and the B wire rope is pulled tight); it is assumed that when the steering gear 41 rotates clockwise, the A wire rope of the wire wheel 53 will be stretched, and the B wire rope will be relaxed; it is assumed that when the steering gear 41 rotates counterclockwise, the A wire rope of the wire wheel 53 will be relaxed, and the B wire rope will be stretched.

[0083] At this time, it is assumed that the No. B2 joint and the No. B5 joint are to be locked, and the following operations are performed: lock start -> the linear drive module advances to match the steering gear end gear 43 with the self-locking end gear 51 of No. A2 -> the steering gear 41 is driven to rotate clockwise for one revolution -> the linear drive module 3 advances to match the steering gear end gear 43 with the self-locking end gear 51 of No. A5 -> the steering gear is driven to rotate clockwise for one revolution -> the linear drive module 3 retreats to the initial position (the steering gear end gear 43 matches the self-locking end gear 51 of No. A1) -> lock end.

[0084] At this time, the No. B2 and No. B5 joints are locked, and if the No. B1, No. B3, and No. B4 joints are to be locked and the No. B2 and No. B5 joints are to be unlocked, the following operations are performed: lock start -> the linear drive module 3 advances to match the steering gear end gear 43 with the self-locking end gear 51 of No. A1 -> the steering gear 41 is driven to rotate clockwise for one revolution -> the linear drive module 3 advances to match the steering gear end gear 43 with the self-locking end gear 51 of No. A2 -> the steering gear 41 is driven to rotate counterclockwise for one revolution -> the linear drive module 3 advances to match the steering gear end gear 43 with the self-locking end gear 51 of No. A3 -> the steering gear 41 is driven to rotate clockwise for one revolution -> the linear drive module 3 advances to match the steering gear end gear 43 with the self-locking end gear 51 of No. A4 -> the steering gear 41 is driven to rotate clockwise for one revolution -> the linear drive module 3 advances to match the steering gear end gear 43 with the self-locking end gear 51 of No. A5 -> the steering gear 41 is driven to rotate counterclockwise for one revolution -> the linear drive module 3 retreats to the initial position (the steering gear end gear 43 matches the self-locking end gear 51 of No. A1) -> lock end.

[0085] As can be seen above, no matter how many operations are to be performed, at most only the steering engine end gear 43 is paired with the self-locking end gear 51 of A1, A2, A3, A4, A5, respectively, the steering engine 41 is rotated (or not rotated), and finally returned to the initial position, so if 3 groups of operation modules are installed, 30 joints of the continuum robot can be controlled to be locked, as shown in the figure, only 3 groups of operation modules are axially connected and fixed, and 3 groups of linear drive modules 3 are installed equidistantly, so that the linear drive modules 3 in all operation modules reach the initial position, the wire ropes of all wire wheels 53 are led to the tail end outlet along the pulley, the six steering engine end gears 43 of the three groups of linear drive modules 3 correspond to the self-locking end gears 51 of the five positions, the joints to be locked are locked, and the joints to be unlocked are unlocked (if the joints need to remain unchanged, the steering engine does not rotate), the locking & unlocking & unchanged operation of 30 joints can be quickly completed in a short time, the efficiency is quite high, and more operation modules can be spliced without increasing the time required for system locking & unlocking & unchanged operation. Figure 12 Figure 12

[0086] The mechanism for locking and unlocking the wire-driven variable stiffness continuum robot provided by the application has a small and compact appearance, is modularly designed, can be added with or reduced in the number of operation modules, is easy to add and operate, does not increase the time required for locking and unlocking, is stable after locking (because the self-locking worm and gear mechanism is used), the wire wheel can be removed and has strong replaceability, and effectively improves the efficiency of controlling the variable stiffness wire-controlled surgical robot and the adaptability to complex surgical tasks.

[0087] The application is used for locking and unlocking the wire-driven variable stiffness continuum robot (wire-driven variable stiffness mechanical arm).

[0088] The above is a further detailed description of the application in combination with specific preferred embodiments, and the specific implementation of the application cannot be limited to these descriptions. For ordinary skilled persons in the technical field to which the application belongs, some simple deductions or replacements can be made without departing from the concept of the application, and all of them should be regarded as falling within the protection scope of the application.​

Claims

1. A mechanism for locking and unlocking a line-driven variable stiffness continuum robot, characterized in that: The device includes a self-locking reel module, a modular housing module, a servo drive module, a linear drive module, and a support module. The modular housing module is connected to and fixed to the support module. The linear drive module is mounted on the support module, and the servo drive module is mounted on the linear drive module, enabling the servo drive module to move back and forth. The self-locking reel module is mounted on the modular housing module, and the servo drive module can unlock or lock after docking with the self-locking reel module. The servo drive module includes a servo bracket, a servo, a servo arm, and a servo end gear. The servo is mounted on the servo bracket, the servo is connected to the servo arm, and the servo arm is connected to the servo end gear. The self-locking reel module includes a self-locking end gear, a worm gear mechanism, a reel, and a line. The self-locking end gear is fixed to the screw of the worm gear mechanism, the reel is fixed to the worm wheel of the worm gear mechanism, and the line is mounted on the reel. The docking process between the servo drive module and the self-locking reel module is as follows: the linear drive module drives the servo drive module to move back and forth, so that the servo end gear of the servo drive module meshes with the self-locking end gear of the self-locking reel module, thereby achieving docking between the servo drive module and the self-locking reel module; the locking and unlocking process of the line-driven variable stiffness continuum robot is as follows: the servo drives the servo arm to rotate, the servo arm drives the servo end gear to rotate, the servo end gear drives the self-locking end gear to rotate, the self-locking end gear drives the reel to rotate through the worm gear mechanism, and the rotation of the reel pulls the line, thereby achieving locking and unlocking of the line-driven variable stiffness continuum robot; Two or more self-locking reel modules are installed on a modular housing module. The worm gear mechanism of one self-locking reel module drives a group of reels, and the group of reels realizes the locking and unlocking of a joint.

2. The mechanism for locking and unlocking line-driven variable stiffness continuum robot according to claim 1, characterized in that: The bracket module includes a first support plate, a second support plate, a motor, a lead screw, and an optical axis. The two ends of the optical axis are connected to the first support plate and the second support plate, respectively. The two ends of the lead screw are connected to the first support plate and the second support plate, respectively. The motor is connected to the lead screw, and the linear drive module is mounted on the lead screw.

3. The mechanism for locking and unlocking line-driven variable stiffness continuum robot according to claim 2, characterized in that: The support module also includes a base plate, a third support plate, an inclined pulley, and a tapered plate for winding. The first support plate, the second support plate, and the third support plate are respectively mounted on the base plate. The first support plate, the second support plate, and the third support plate are parallel to each other. The inclined pulley is mounted on the second support plate, and the tapered plate is mounted on the third support plate.

4. The mechanism for locking and unlocking line-driven variable stiffness continuum robot according to claim 2, characterized in that: The linear drive module includes a linear drive module mounting base, on which a lead screw nut is provided. The lead screw nut is mounted on the lead screw. The linear drive module mounting base is provided with an optical axis hole through which the optical axis passes.

5. The mechanism for locking and unlocking line-driven variable stiffness continuum robot according to claim 1, characterized in that: The servo end gear is a non-full-tooth gear, with one part having teeth and the other part being toothless.

6. The mechanism for locking and unlocking line-driven variable stiffness continuum robot according to claim 1, characterized in that: The self-locking reel module also includes a straight pulley, on which the rope is tensioned.

7. The mechanism for locking and unlocking line-driven variable stiffness continuum robot according to claim 1, characterized in that: The modular shell module includes an arc-shaped splicing shell and a front and rear splicing base plate. The arc-shaped splicing shell is connected to the front and rear splicing base plate. The end of the arc-shaped splicing shell away from the front and rear splicing base plate is provided with front and rear splicing protrusions. The bottom surface of the front and rear splicing base plate is provided with front and rear splicing grooves. When splicing front and rear, the front and rear splicing protrusions of the arc-shaped splicing shell of the rear modular shell module are aligned with the front and rear splicing grooves of the front modular shell module's front and rear splicing base plate. When splicing circumferentially, the arc-shaped splicing shells of two or more modular shell modules are spliced ​​into a segmented circle or arc.

Images