A Continuum Robot Based on a Six-Bar Tensegrity Structure and Its Control Method

Abstract

The present invention discloses a continuum robot based on a six-bar tensegrity structure and its control method in the field of robotics. The continuum robot includes: a plurality of unit bodies, connecting members, and a driving device. The plurality of unit bodies are sequentially connected through the connecting members to form a continuum. The unit body includes a telescopic mechanism, a transmission mechanism, and a pair of fixing plates. Among them, the telescopic mechanism is installed between the pair of fixing plates, and the telescopic mechanism is a six-bar tensegrity structure composed of six rods and twenty-four elastic ropes. The telescopic mechanisms of two adjacent unit bodies are connected through the connecting members. The continuum robot provided by the present invention has high movement ability and movement flexibility, and can avoid obstacles when moving forward.

Description

Technical Field

[0001] The invention relates to the technical field of robots, and in particular to a continuum robot based on a six-bar tensegrity structure and a control method thereof. Background Art

[0002] Traditional robots are usually designed with rigid structures and discrete motion joints, typically with fixed joints and links. These robots are widely used in the industrial field due to their precise control and strong structure. However, when faced with complex environments, flexible tasks or bio-simulation requirements, such as working in narrow pipes, detecting ruins after earthquakes or simulating the movement of worms, the flexibility of traditional robots is insufficient. Tensegrity is a spatial structural system based on the interaction of tension and pressure. It combines cables and rods to form a unique self-balancing and self-supporting structure. This structure is light, stable and efficient. Among various tensegrity structures, the six-bar tensegrity structure consists of six rods and twenty-four ropes, showing a symmetrical geometry.

[0003] There is currently no robot that can combine the lightweight, high strength, and excellent deformation and load-bearing capacity of a six-bar tensegrity structure with the adaptability and flexibility of a continuum robot. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide a continuum robot based on a six-bar tensegrity structure and a control method thereof, wherein the continuum robot has high movement ability and movement flexibility and can avoid obstacles while moving.

[0005] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0006] On the one hand, the present invention provides a continuum robot based on a six-bar tensegrity structure, comprising a plurality of unit bodies, a connecting member and a driving device, wherein the plurality of unit bodies are sequentially connected by the connecting member to form a continuum;

[0007] The unit body includes a telescopic mechanism, a transmission mechanism and a pair of fixed plates, wherein the telescopic mechanism is installed between the pair of fixed plates, and the telescopic mechanism includes six rods and twenty-four elastic ropes, and the ends of any rod are connected to the ends of other rods closest to it through four elastic ropes to form a six-rod tensegrity structure;

[0008] The transmission mechanism includes a connecting rod transmission mechanism, a crank transmission mechanism and a gear transmission mechanism;

[0009] The driving device is connected to the telescopic mechanism through a gear transmission mechanism, and drives the telescopic mechanism to perform a contraction action through the gear transmission mechanism;

[0010] The driving device is drivingly connected to the crank transmission mechanism through a gear transmission mechanism, and the crank transmission mechanism is drivingly connected to the connecting rod transmission mechanisms of two adjacent unit bodies through a connecting member. The connecting rod transmission mechanism is drivingly connected to the telescopic mechanism of the corresponding unit body. The driving device drives the crank transmission mechanism to move through the driving gear transmission mechanism, and then drives the connecting rod transmission mechanism to move. The telescopic mechanisms of two adjacent unit bodies are driven by the connecting rod transmission mechanism to perform an extending action.

[0011] Furthermore, the gear transmission mechanism includes an internal gear, a first gear, a concave-core gear, a second gear, a third gear, a ratchet, a detent pawl, and a first bevel gear;

[0012] Among them, the concave-core gear, the third gear, the second gear, and the first gear are arranged on one side of the fixed plate away from the telescopic mechanism. The center of the concave-core gear coincides with the center of the fixed plate. The third gear, the second gear, and the first gear are arranged in meshing sequence towards the edge of the fixed plate, and the centers of the concave-core gear, the third gear, the second gear, and the first gear are arranged collinearly;

[0013] A circular groove is formed at the center of the concave-core gear. The ratchet coincides with the center of the concave-core gear and is placed in the circular groove of the concave-core gear in a first direction, where the first direction is counterclockwise or clockwise; the detent pawl is arranged in the circular groove and is used to enable the ratchet to rotate only in the first direction along with the concave-core gear;

[0014] The internal gear is sleeved on the edge of the fixed plate and can rotate around the fixed plate. Teeth are distributed on both sides of the internal gear relative to the fixed plate, and the teeth on the same side as the first gear mesh with the first gear;

[0015] The first bevel gear is connected to one end of the rod close to the fixed plate, and the teeth on the same side of the internal gear as the first bevel gear mesh with the first bevel gear.

[0016] Furthermore, the connecting rod transmission mechanism includes twelve symmetric bent rods. The bending angle of the bent rod is °. The bent rods are grouped in pairs. The two bent rods in the same group are hinged to each other at the bending point, and there is an overlapping part in the included angle area of the two bent rods in the same group. The two adjacent ends of the adjacent two groups of bent rods are hinged to each other, forming six inner folding points and six outer folding points.

[0017] Further, the connecting member includes three arcuate connecting rods. The fixing plate is provided with six sliding grooves in the radial direction, and the included angle between adjacent sliding grooves is 60°. The three arcuate connecting rods pass through three non-adjacent sliding grooves on the fixing plate, and pass through three corresponding sliding grooves on the fixing plates of adjacent unit bodies. The three end portions of the three arcuate connecting rods on the same side are connected to the end portions of three adjacent rods in the adjacent unit body, and are connected to three mutually spaced inner folding points among the six inner folding points in the adjacent unit body.

[0018] Further, the crank drive mechanism includes a first connecting rod and a second connecting rod; one end of the first connecting rod is fixedly connected to the center of the ratchet wheel, and the other end is hinged to one end of the second connecting rod. The other end of the second connecting rod is hinged to an inner folding point that is not connected to the connecting member in the link drive mechanism through a sliding groove on the fixing plate.

[0019] Further, the continuum robot further includes a cable device. The cable device is arranged at both ends of the continuum. The cable device includes a cable driving motor, a cable reel and a cable;

[0020] The fixing plate is provided with a through hole. One end of the cable is wound around the cable reel, and the other end passes through the fixing plates of at least two unit bodies and is fixed to the fixing plate farthest from the cable reel. The output end of the cable driving motor is in transmission connection with the cable reel.

[0021] Further, the driving device includes a driving motor, a second bevel gear and a third bevel gear. The driving motor is arranged outside the unit body and is mounted on the fixing plate. The second bevel gear is connected to the output end of the driving motor. The third bevel gear is vertically meshed with the second bevel gear. The third bevel gear is coaxially connected with the first gear, so that the first gear and the third bevel gear rotate synchronously.

[0022] Further, the continuum robot further includes a vision module, which is arranged at the forefront of the continuum robot and is used for acquiring image information in front of the continuum robot;

[0023] The continuum robot further includes a tactile module. The tactile module includes a first sensor, a second sensor and a spring. The spring is connected between the first sensor and the second sensor. The first sensor is mounted on the fixing plate of the unit body at the forefront of the continuum robot. When the first sensor and the second sensor are in contact, the first sensor feeds back a signal.

[0024] Further, the continuum robot further includes a flexible skin, and the flexible skin wraps the outer surface of the continuum robot.

[0025] On the other hand, the present invention provides a control method for the continuum robot based on the six-bar tensegrity structure, including:

[0026] Taking the moving direction of the continuum robot as the front, controlling the telescopic mechanisms of a plurality of continuous unit bodies of the continuum robot to contract sequentially from front to back;

[0027] After the multiple continuous unit bodies have been contracted from front to back in sequence, the telescopic mechanisms of the multiple continuous unit bodies of the continuum robot are controlled to extend from back to front in sequence to complete one creeping motion;

[0028] The continuum robot is made to repeatedly perform creeping motions and is controlled to move forward.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The continuum robot based on the six-bar tensegrity structure provided by the present invention utilizes the characteristic that when the positions of the rods of the six-bar tensegrity structure change, the overall body length can be extended and retracted under the joint action of the rods and elastic ropes. A telescopic mechanism is constructed based on the six-bar tensegrity structure, and a gear transmission mechanism, a connecting rod transmission mechanism, a crank transmission mechanism and a connecting piece are provided. The driving device is connected to the telescopic mechanism through the gear transmission mechanism, and under the transmission action of the gear transmission mechanism, the driving device can drive the telescopic mechanism to perform a contraction action; the driving device is connected to the crank transmission mechanism through the gear transmission mechanism, and the crank transmission mechanism is connected to the connecting rod transmission mechanisms of two adjacent unit bodies through a connecting piece, the connecting rod transmission mechanism is connected to the telescopic mechanism of the corresponding unit body, and the driving device can drive the gear transmission mechanism to move The gear transmission mechanism drives the crank transmission mechanism to move, and then drives the connecting rod transmission mechanism of the two adjacent unit bodies to move, and finally drives the telescopic mechanism of the two adjacent unit bodies to perform the extension action. Under the joint constraint of the gear transmission mechanism, the connecting rod transmission mechanism, the crank transmission mechanism and the connecting member, the rods of the six-bar tensegrity structure move along a fixed motion trajectory, so that the contraction and extension actions of the unit body are performed alternately, so that the position of the rods of the six-bar tensegrity structure of the unit body changes. Under the joint action of the rods and the elastic rope, the unit body achieves the function of contraction and extension, so that the continuum robot can achieve the creeping function under the control of the motor, thereby improving the movement ability of the continuum robot. The continuum robot combines the lightweight, high strength and excellent deformation ability and load-bearing capacity of the six-bar tensegrity structure.

[0031] The continuum robot based on the six-bar tensegrity structure provided by the present invention can achieve the first-level bending function of the continuum towards one side by setting the cable device to shorten the length of the cables on the same side and lengthen the length of the cables on the other side, or can achieve the second-level bending function of the continuum by shortening the cables on one side of the front two unit bodies, lengthening the cables on the same side of the two unit bodies at the tail end, lengthening the cables on the other side of the front two unit bodies, and shortening the cables on the same other side of the two unit bodies at the tail end, thus improving the flexibility of the continuum robot.

[0032] The continuum robot based on the six-bar tensegrity structure provided by the present invention can provide visual and tactile feedback by setting the vision module and the tactile module, helping the continuum robot perceive the surrounding environment, such as measuring the path ahead and detecting the pressure when in contact, so as to conduct path planning and obstacle avoidance, thereby improving the environmental adaptability of the continuum robot. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic structural diagram of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention;

[0034] Figure 2 It is a schematic side view structural diagram of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention;

[0035] Figure 3 For the present invention Figure 2 It is a schematic A-A side sectional view of the continuum robot based on the six-bar tensegrity structure provided by the embodiment shown in the present invention;

[0036] Figure 4 For the present invention Figure 2 It is a schematic B-B side sectional view of the continuum robot based on the six-bar tensegrity structure provided by the embodiment shown in the present invention in the non-elongated state;

[0037] Figure 5 For the present invention Figure 2 It is a schematic B-B side sectional view of the continuum robot based on the six-bar tensegrity structure provided by the embodiment shown in the present invention in the elongated state;

[0038] Figure 6 It is a schematic structural diagram of the end face of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention;

[0039] Figure 7 It is a schematic diagram of the peristaltic state of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention;

[0040] Figure 8 It is a schematic diagram of the first-angle state of the first-level bending of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention;

[0041] Figure 9 Schematic diagram of the first bending state of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention, at the second angle;

[0042] Figure 10 Schematic diagram of the second bending state of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention, at the first angle;

[0043] Figure 11 Schematic diagram of the second bending state of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention, at the second angle;

[0044] Figure 12 Schematic diagram of the structure of the six-bar tensegrity structure of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention, at the first angle;

[0045] Figure 13 Schematic diagram of the structure of the six-bar tensegrity structure of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention, at the second angle;

[0046] Figure 14 Schematic diagram of the structure of a set of connecting pieces of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention;

[0047] Figure 15 Schematic diagram of the structure of the driving device and the first gear of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention, at the first angle;

[0048] Figure 16 Schematic diagram of the structure of the driving device and the first gear of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention, at the second angle;

[0049] Figure 17 Schematic diagram of the structure of the vision module, the tactile module and the flexible skin of the continuum robot based on the six-bar tensegrity structure provided by the embodiment of the present invention.

[0050] In the figure: 1. Driving motor; 2. Second bevel gear; 3. Third bevel gear; 4. First gear; 5. Second gear; 6. Third gear; 7. Concave-core gear; 8. Ratchet; 9. Stopping pawl; 10. Internal gear; 11. Fixed plate; 12. First connecting rod; 13. Second connecting rod; 14. Link transmission mechanism; 15. Rod member; 16. Elastic cord; 17. First bevel gear; 18. Connecting piece; 19. Cable pulling device; 20. Cable; 21. Cable winding driving motor; 22. Reel; 23. Vision module; 24. Flexible skin; 25. First sensor; 26. Second sensor; 27. Spring. DETAILED DESCRIPTION

[0051] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0052] Example 1

[0053] This embodiment provides a continuum robot based on a six-bar tensegrity structure. Figure 1 and Figure 2 As shown, it includes five unit bodies, a connecting member 18 and a driving device, and the five unit bodies are connected in sequence through the connecting member 18 to form a continuous body.

[0054] The unit body includes a telescopic mechanism, a transmission mechanism and a pair of fixed plates 11, wherein the telescopic mechanism is installed between the pair of fixed plates 11. Figure 12 and Figure 13 As shown, the telescopic mechanism includes six rods 15 and twenty-four elastic ropes 16. Both ends of each rod 15 are connected to the end points of the rod 15 closest to it through four elastic ropes 16 to form a six-rod tensegrity structure. The six-rod tensegrity structure is a regular icosahedron, each face of which is an equilateral triangle. The telescopic mechanisms of two adjacent unit bodies are connected by a connecting member 18.

[0055] The transmission mechanism includes a connecting rod transmission mechanism 14, a crank transmission mechanism and a gear transmission mechanism. The driving device is connected to the telescopic mechanism through the gear transmission mechanism. Under the transmission action of the gear transmission mechanism, the driving device can drive the telescopic mechanism to perform a contraction action.

[0056] The driving device is connected to the crank transmission mechanism through a gear transmission mechanism, and the crank transmission mechanism is connected to the connecting rod transmission mechanism 14 of two adjacent units through a connecting piece 18, and the connecting rod transmission mechanism 14 is connected to the telescopic mechanism of the corresponding unit. The driving device can drive the gear transmission mechanism to move, and drive the crank transmission mechanism to move, and then drive the connecting rod transmission mechanism 14 of the two adjacent units to move, and finally drive the telescopic mechanism of the two adjacent units to perform an extension action.

[0057] like Figure 3As shown, the gear transmission mechanism includes an internal gear 10, a first gear 4, a concave-core gear 7, a second gear 5, a third gear 6, a ratchet 8, three detent claws 9, and a first bevel gear 17. Among them, the concave-core gear 7, the third gear 6, the second gear 5, and the first gear 4 are arranged on the side of the fixed plate 11 away from the telescopic mechanism. The center of the concave-core gear 7 coincides with the center of the fixed plate 11. The third gear 6, the second gear 5, and the first gear 4 are arranged in meshing sequence toward the edge of the fixed plate 11, and the centers of the concave-core gear 7, the third gear 6, the second gear 5, and the first gear 4 are arranged collinearly.

[0058] The ratchet 8 coincides with the center of the concave-core gear 7 and is placed in the circular groove of the concave-core gear 7 in a first direction, where the first direction is counterclockwise or clockwise. The detent claws 9 are also arranged in the circular groove of the concave-core gear 7. The three detent claws 9 are evenly distributed around the ratchet 8, and the three detent claws 9 hold the central ratchet 8 in the first direction, so that the ratchet 8 can only rotate with the concave-core gear 7 in the first direction.

[0059] The internal gear 10 is sleeved on the edge of the fixed plate 11 and can rotate around the fixed plate 11. Teeth are distributed on both sides of the internal gear 10 relative to the fixed plate 11, and the teeth on the same side as the first gear 4 mesh with the first gear 4.

[0060] The first bevel gear 17 is connected to one end of the rod 15 close to the fixed plate 11, and the teeth on the internal gear 10 on the same side as the first bevel gear 17 mesh with the first bevel gear 17.

[0061] As Figure 15 and Figure 16 shown, in this embodiment, the driving device includes a driving motor 1, a second bevel gear 2, and a third bevel gear 3. The driving motor 1 is arranged outside the unit body and mounted on the fixed plate 11. The second bevel gear 2 is connected to the output end of the driving motor 1. The third bevel gear 3 is vertically meshed with the second bevel gear 2, and the third bevel gear 3 is coaxially connected to the first gear 4, so that the first gear 4 and the third bevel gear 3 rotate synchronously.

[0062] When the driving motor 1 works, through the transmission of the vertically meshed second bevel gear 2 and third bevel gear 3, the first gear 4 can be driven to rotate. The rotation of the first gear 4 will drive the internal gear 10 and the concave-core gear 7 to rotate. At this time, under the action of the detent claws 9, the ratchet 8 will be driven to rotate.

[0063] As Figure 4As shown, the link drive mechanism 14 includes twelve symmetric bent rods. The bending angle of the bent rods is 120°. The bent rods are grouped in pairs. Two bent rods in the same group are hinged to each other at the bending point, and there is an overlapping part in the included angle area of the two bent rods in the same group. The two ends of adjacent groups of bent rods close to each other are hinged to form six inner folding points and six outer folding points. The shape of the link drive mechanism 14 can be switched between a diastolic state and a systolic state. As Figure 4 is a schematic cross-sectional view of the continuum robot in the non-elongated state. At this time, the link drive mechanism 14 is in the diastolic state; Figure 5 is a schematic cross-sectional view of the continuum robot in the elongated state. At this time, the link drive mechanism 14 is in the systolic state.

[0064] As Figure 14 shown, the connecting member 18 includes three bow-shaped connecting rods. The bow-shaped connecting rods are composed of three cross rods and two vertical rods. The cross rods and the vertical rods are alternately connected, and the two vertical rods point in the same direction relative to the middle cross rod. The connecting member 18 composed of three bow-shaped connecting rods can ensure that there is enough space in the middle of the two unit bodies to set other drive mechanisms while playing a driving role, so that the operation of each drive mechanism does not conflict. Six chutes are arranged on the fixing plate 11 along the radial direction, and the included angle between adjacent chutes is 60°. The three bow-shaped connecting rods pass through three non-adjacent chutes on the fixing plate 11 and pass through three corresponding chutes at the corresponding positions on the fixing plate 11 of adjacent unit bodies. As Figure 7 shown, the three ends of the three bow-shaped connecting rods on the same side are connected to the ends of three adjacent rods 15 in the adjacent unit body, and are connected to three mutually spaced inner folding points among the six inner folding points of the link drive mechanism 14 connecting the adjacent unit bodies. The three end points on the other side of the three bow-shaped connecting rods are connected in the same way.

[0065] When the three bow-shaped connecting rods slide along the three chutes towards or away from the center, the connected link drive mechanism 14 is also switched between the diastolic state and the systolic state, and drives the three rods 15 in the adjacent unit body to tilt towards the fixing plate 11 or stand up in the direction away from the fixing plate 11; the three rods 15 connecting the same connecting member 18 in the six-bar tensegrity structure are divided into a group. When the two groups of rods 15 in the six-bar tensegrity structure in the unit body tilt towards the fixing plate 11 at the same time, the unit body completes the contraction action, and vice versa for the elongation action.

[0066] As Figure 3 shown, the crank drive mechanism includes a first link 12 and a second link 13; one end of the first link 12 is fixedly connected to the center of the ratchet 8, and the other end is hinged to one end of the second link 13. The other end of the second link 13 is hinged to an inner folding point of the link drive mechanism 14 that is not connected to the connecting member 18 through a chute on the fixing plate 11.

[0067] The rotation of the ratchet 8 drives the rotation of the first connecting rod 12, which in turn drives the second connecting rod 13 to reciprocate along the sliding groove, and finally drives the connecting rod transmission mechanism 14 to switch between the diastolic state and the systolic state.

[0068] The working principle of the continuum robot based on the six-bar tensegrity structure provided in this embodiment is as follows:

[0069] (1) Contract the unit cell: Start the driving motor 1. Through the transmission of the vertically meshing second bevel gear 2 and third bevel gear 3, the first gear 4 rotates in the first direction and drives the internal gear 10 to rotate in the first direction. Since the teeth on the other side of the internal gear 10 mesh with the first bevel gear 17 at the end of the rod 15 of the six-bar tensegrity structure, the internal gear 10 drives the first bevel gear 17 to rotate, causing the three rods 15 of the six-bar tensegrity structure to tilt towards the fixed plate 11. When the six rods 15 of the six-bar tensegrity structure of a certain unit cell all tilt towards the approaching fixed plate 11, under the action of the twenty-four elastic ropes 16, the two fixed plates 11 on both sides of the six-bar tensegrity structure in the unit cell approach each other, and the unit cell completes contraction. At the same time, the first gear 4 rotates in the first direction, and through the second gear 5 and third gear 6, it is transmitted to the concave core gear 7, driving the concave core gear 7 to rotate in the second direction. At this time, since the three detent claws 9 in the central circular groove of the concave core gear 7 are distributed around the ratchet 8 and embrace in the first direction, the ratchet 8 cannot be driven to rotate when the concave core gear 7 rotates in the second direction.

[0070] (2) Stretch the unit cell: Start the driving motor 1. Through the transmission of the vertically meshing second bevel gear 2 and third bevel gear 3, the first gear 4 rotates in the second direction. Similarly to when the unit cell contracts, the rotation of the first gear 4 in the second direction drives the internal gear 10 to rotate in the second direction and drives the concave core gear 7 to rotate in the first direction. At this time, under the action of the detent claws 9, the ratchet 8 will be driven to rotate in the first direction, driving the rotation of the first connecting rod 12. Under the transmission action of the second connecting rod 13, the six internal inflection points of the connecting rod transmission mechanism 14 move towards the center of the fixed plate 11 along the sliding groove on the fixed plate 11 at the same time, and drive the connecting piece 18 to move towards the center of the fixed plate 11. Since the connecting piece 18 is connected to the three rods 15 of the six-bar tensegrity structure, the ends of the three rods 15 with the first bevel gear 17 will move towards the center of the fixed plate 11 at the same time, and the meshing between the three first bevel gears 17 and the internal gear 10 is disconnected at the same time. When the six rods 15 of the six-bar tensegrity structure all move towards the center of the fixed plate 11, under the action of the twenty-four elastic ropes 16, the two fixed plates 11 on both sides of the six-bar tensegrity structure in the unit cell move away from each other, and the unit cell completes stretching.

[0071] It should be noted that the first direction is the counterclockwise direction or the clockwise direction, and the second direction is the direction opposite to the first direction.

[0072] Under the combined restraint of the gear transmission mechanism, the link transmission mechanism 14, the crank transmission mechanism, and the connecting member 18, the rod 15 of the six-bar tensegrity structure moves along a fixed motion trajectory, causing the contraction and elongation actions of the unit body to alternate, and the continuum robot can achieve a peristaltic function, such as Figure 7 FIG. 4 is a schematic diagram of the peristaltic state of the continuum robot. At this time, the two unit bodies at one end of the continuum robot are in the extended state, the two unit bodies at the other end are in the contracted state, and the middle unit body is in the initial state.

[0073] Embodiment 2

[0074] This embodiment provides a continuum robot based on a six-bar tensegrity structure. Different from Embodiment 1, in this embodiment, the continuum robot based on the six-bar tensegrity structure further includes twelve cable devices 19, such as Figure 1 and Figure 6 As shown, twelve cable devices 19 are arranged at both the head and tail ends of the continuum. Six cable devices 19 are arranged at each end. The six cable devices 19 are installed on the fixing plates 11 at the head and tail, and are distributed in a regular hexagon. The cable device 19 includes a cable winding drive motor 21, a reel 22, and a cable 20.

[0075] Six through holes are formed in each fixing plate 11, and the six through holes are also distributed in a regular hexagon. One end of the cable 20 of each cable device 19 is wound around the reel 22, and the other end passes through five fixing plates 11 through the corresponding through hole, and is fixed on the fixing plate 11 farthest from this cable device 19. The output end of the cable winding drive motor 21 is connected to the reel 22.

[0076] In the state where all five unit bodies of the continuum robot are extended, the cable winding drive motor 21 drives the reel 22 to rotate, shortening the length of the cables 20 on the same side of the continuum robot and lengthening the length of the cables 20 on the other side, so that the continuum realizes a primary bending function, such as Figure 8 and Figure 9 shown.

[0077] Or shorten the cables 20 on one side of the two unit bodies at one end of the continuum robot and elongate them on the other side, and bend the two unit bodies at the other end of the continuum robot in the opposite direction, so that the continuum realizes a secondary bending function, such as Figure 10 and Figure 11 shown.

[0078] Embodiment 3

[0079] This embodiment provides a continuum robot based on a six-bar tensegrity structure. Different from Embodiment 1, in this embodiment, the continuum robot further includes a tactile module, which includes a first sensor 25, a second sensor 26, and a spring 27. The spring 27 is connected between the first sensor 25 and the second sensor 26. The first sensor 25 is installed on the fixing plate 11 of the unit body at the very front end of the continuum robot, as Figure 17 shown. The continuum robot provided in this embodiment is provided with a total of six groups of tactile modules, which are arranged in a circular pattern at the front end of the continuum robot.

[0080] The continuum robot further includes a vision module 23, which is arranged at the very front end of the continuum robot and is used to obtain image information in front of the continuum robot.

[0081] When the tactile module of the continuum robot touches an obstacle, the spring 27 will contract, causing the first sensor 25 and the second sensor 26 of some groups of tactile modules to come into contact and feedback signals. When the tactile module feedbacks signals or the vision module 23 determines that there is an obstacle ahead, at this time, the control of the cable device 19 works, and the function of turning and avoiding obstacles of the continuum robot can be achieved.

[0082] In this embodiment, the continuum robot further includes a flexible skin 24, as Figure 17 shown. The flexible skin 24 wraps the outer surface of the continuum robot and can protect the internal mechanism.

[0083] Embodiment 4

[0084] This embodiment provides a control method for a continuum robot based on a six-bar tensegrity structure as described in Embodiment 1 or Embodiment 2 or Embodiment 3, including:

[0085] Taking the moving direction of the continuum robot as the front, controlling the telescopic mechanisms of multiple consecutive unit bodies of the continuum robot to contract sequentially from front to back;

[0086] After multiple consecutive unit bodies have contracted sequentially from front to back, controlling the telescopic mechanisms of multiple consecutive unit bodies of the continuum robot to extend sequentially from back to front to complete one peristaltic motion;

[0087] Making the continuum robot repeatedly execute peristaltic motions to control the continuum robot to move forward.

[0088] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only used to explain the relative positional relationship and movement conditions between components in a specific posture. If this specific posture changes, the directional indication will also change accordingly. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0089] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific circumstances.

[0090] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit and scope protected by the present invention and the claims, and all of these are within the protection scope of the present invention.

Claims

1. A continuum robot based on a six-bar tensegrity structure, characterized in that: It comprises a plurality of unit bodies, a connecting member (18) and a driving device, wherein the plurality of unit bodies are connected in sequence through the connecting member (18) to form a continuous body; The unit body comprises a telescopic mechanism, a transmission mechanism and a pair of fixed plates (11), wherein the telescopic mechanism is installed between the pair of fixed plates (11), the telescopic mechanism comprises six rods (15) and twenty-four elastic ropes (16), and the end of any rod (15) is connected to the end of the nearest other rod (15) through four elastic ropes (16), so as to form a six-rod tensegrity structure; The transmission mechanism comprises a connecting rod transmission mechanism (14), a crank transmission mechanism and a gear transmission mechanism; The driving device is connected to the telescopic mechanism through a gear transmission mechanism, and drives the telescopic mechanism to perform a contraction action through the gear transmission mechanism; The driving device is connected to the crank transmission mechanism via a gear transmission mechanism, and the crank transmission mechanism is connected to the connecting rod transmission mechanism (14) of two adjacent unit bodies via a connecting piece (18), and the connecting rod transmission mechanism (14) is connected to the telescopic mechanism of the corresponding unit body; the driving device drives the crank transmission mechanism to move by driving the gear transmission mechanism, thereby driving the connecting rod transmission mechanism (14) to move, and drives the telescopic mechanism of the two adjacent unit bodies to perform an extension action via the connecting rod transmission mechanism (14); The gear transmission mechanism comprises an internal gear (10), a first gear (4), a concave heart gear (7), a second gear (5), a third gear (6), a ratchet (8), a locking pawl (9) and a first bevel gear (17); The concave gear (7), the third gear (6), the second gear (5) and the first gear (4) are arranged on a side of the fixed plate (11) away from the telescopic mechanism, the center of the concave gear (7) coincides with the center of the fixed plate (11), the third gear (6), the second gear (5) and the first gear (4) are arranged in a meshing manner in a direction toward the edge of the fixed plate (11), and the centers of the concave gear (7), the third gear (6), the second gear (5) and the first gear (4) are arranged in a colinear manner; A circular groove is formed at the center of the concave heart gear (7); the ratchet (8) coincides with the center of the concave heart gear (7) and is placed in the circular groove of the concave heart gear (7) in a first direction, wherein the first direction is a counterclockwise direction or a clockwise direction; the stop pawl (9) is arranged in the circular groove and is used to enable the ratchet (8) to rotate only in the first direction along with the concave heart gear (7); The internal gear (10) is sleeved on the edge of the fixed plate (11) and can rotate around the fixed plate (11); gear teeth are distributed on both sides of the internal gear (10) relative to the fixed plate (11), and the gear teeth on the same side as the first gear (4) are meshed with the first gear (4); The first bevel gear (17) is connected to one end of the rod (15) close to the fixed plate (11), and the gear teeth on the internal gear (10) on the same side as the first bevel gear (17) are meshed with the first bevel gear (17).

2. The continuum robot based on a six-bar tensegrity structure according to claim 1, characterized in that: The connecting rod transmission mechanism (14) comprises twelve symmetrical bent rods, each having a bending angle of 120°. The bent rods are arranged in groups of two, and the two bent rods in the same group are hinged to each other at a bending point. The angle regions of the two bent rods in the same group have overlapping portions, and the two ends of two adjacent groups of bent rods are hinged to each other to form six inner bending points and six outer bending points.

3. The continuum robot based on a six-bar tensegrity structure according to claim 2, characterized in that: The connecting member (18) comprises three bow-shaped connecting rods, the fixed plate (11) is provided with six slide grooves along the radial direction, the angle between adjacent slide grooves is 60 degrees, the three bow-shaped connecting rods pass through three slide grooves on the fixed plate (11) that are not adjacent to each other, and pass through three slide grooves at corresponding positions on the fixed plate (11) of adjacent units, and the three ends of the three bow-shaped connecting rods located on the same side are connected to the ends of three adjacent rods (15) in the adjacent units, and are connected to three mutually spaced inner inflection points among the six inner inflection points in the adjacent units.

4. The continuum robot based on a six-bar tensegrity structure according to claim 3, characterized in that: The crank transmission mechanism comprises a first connecting rod (12) and a second connecting rod (13); one end of the first connecting rod (12) is fixedly connected to the center of the ratchet wheel (8), and the other end is hinged to one end of the second connecting rod (13); the other end of the second connecting rod (13) is hinged to an inner folding point in the connecting rod transmission mechanism (14) that is not connected to the connecting member (18) through a sliding groove on the fixing plate (11).

5. The continuum robot based on a six-bar tensegrity structure according to claim 1, characterized in that: It also includes a rope pulling device (19), the rope pulling device (19) being arranged at both ends of the continuum, the rope pulling device (19) comprising a rope winding drive motor (21), a winding shaft (22) and a rope pulling device (20); A through hole is provided on the fixed plate (11); one end of the pull rope (20) is wound around the reel (22); the other end passes through the fixed plates (11) of at least two unit bodies and is fixed on the fixed plate (11) farthest from the reel (22); and the output end of the rope winding drive motor (21) is drivingly connected to the reel (22).

6. The continuum robot based on a six-bar tensegrity structure according to claim 1, characterized in that: The driving device comprises a driving motor (1), a second bevel gear (2) and a third bevel gear (3); the driving motor (1) is arranged outside the unit body and mounted on a fixing plate (11); the second bevel gear (2) is connected to the output end of the driving motor (1); the third bevel gear (3) is vertically meshed with the second bevel gear (2); the third bevel gear (3) is coaxially connected to the first gear (4), so that the first gear (4) and the third bevel gear (3) rotate synchronously.

7. The continuum robot based on a six-bar tensegrity structure according to claim 1, characterized in that: It also includes a visual module (23) disposed at the front end of the continuum robot and used to obtain image information in front of the continuum robot; The invention also comprises a tactile module, the tactile module comprising a first sensor (25), a second sensor (26) and a spring (27), the spring (27) being connected between the first sensor (25) and the second sensor (26), the first sensor (25) being mounted on a fixing plate (11) of a unit body at the front end of the continuum robot, and when the first sensor (25) and the second sensor (26) are in contact, the first sensor (25) feeds back a signal.

8. The continuum robot based on a six-bar tensegrity structure according to claim 1, characterized in that: It also includes a flexible skin (24), which is wrapped around the outer surface of the continuum robot.

9. A control method for a continuum robot based on a six-bar tensegrity structure according to any one of claims 1 to 8, characterized in that: include: Taking the moving direction of the continuum robot as the front, controlling the telescopic mechanisms of a plurality of continuous unit bodies of the continuum robot to contract in sequence from front to back; After the plurality of continuous unit bodies have been contracted successively from front to back, the telescopic mechanisms of the plurality of continuous unit bodies of the continuum robot are controlled to extend successively from back to front to complete one creeping motion; The continuum robot is made to repeatedly perform creeping motions and is controlled to move forward.

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