A bird-neck saddle-shaped bionic joint and a motion module and a bionic continuum robotic arm composed of the same

Abstract

The present invention proposes a bird-neck saddle-shaped bionic joint and a motion module and a bionic continuum robot composed of the same, which belong to the field of engineering bionic technology. Aiming at the problem of how to achieve the motion stability, flexibility and high load of a continuum robot in a confined or complex space, and inspired by the stabilization function of the bird's neck, the main motion connection mode of the bird's neck joint is analyzed and extracted to obtain a bird-neck saddle-shaped bionic joint formed by connecting a front saddle-shaped joint with two small joints at the rear. Two bionic joints can form a single-stage motion module, and further form a multi-stage motion module. The motion modules can be connected by cable ties, rubber bands, tension springs, piano wires, etc. to imitate the tension and pressure of tendons, ligaments and muscles. The above flexible connection can be used between adjacent segments or across one or more levels of segments to achieve the control changes of various postures such as flexion movement and twisting movement in the ventral and dorsal direction of the bionic robot arm, and keep it stable during movement.

Description

Technical Field

[0001] The invention belongs to the technical field of engineering bionics. Background Art

[0002] With the development of modern science and technology and the improvement of industrial level, it has become more and more common for robots to replace manual labor. Automated robotic arms have gradually been applied in many fields such as healthcare, automobile manufacturing, aerospace, food processing and agricultural production, improving production efficiency and work quality. These traditional industrial robotic arms have the advantages of simple control, strong load capacity, good stability and low cost, but their movement space is relatively limited and cannot be used in confined space or complex space operation scenarios. In fact, in many fields such as industrial production, agricultural production, energy, aerospace, etc., there are many operating scenarios that require automated operations in confined or complex spaces, and new robotic arms are urgently needed to fill the technical gap.

[0003] The continuum robot arm is highly flexible and has the ability to continuously deform. It can achieve flexible movement and fine operation in various confined spaces, filling the gap in the application scenarios of traditional industrial robot arms. The continuum robot arm can operate in complex spaces in large-scale equipment such as aerospace, aviation, ships, and nuclear power, and complete the monitoring and maintenance of target equipment; in high-risk areas, the continuum robot arm can replace or assist staff in search and rescue work at the scene of earthquake collapse, underground rescue, fire, etc., to ensure the safety of disaster relief personnel; in the medical field, it can replace medical staff to perform some surgical operations, carry out minimally invasive resection surgery, laparoscopic surgery, etc., and reduce medical labor costs. In summary, the continuum robot arm has the characteristics of multiple degrees of freedom, high flexibility and high fault tolerance and coordination ability, and can adapt to complex and changing environments, becoming a hot spot in the research of bionic robots.

[0004] At present, continuum robotic arms are in the development stage and the technology is not yet fully mature. In-depth research on the mechanism design, drive technology and path planning technology of continuum robots and the development of continuum robotic arms with flexibility, stability and load capacity have very important scientific significance and practical value, which will help enhance the country's core competitiveness and comprehensive economic strength in the field of cutting-edge robotics technology.

[0005] The neck-spine-tail mechanism evolved in the long-term natural selection process of bird necks is a spatial nonlinear super-redundant multi-joint structure that integrates local small displacements into large overall bending and torsion displacements, and plays a major role in completing the head stability function. This biological mechanism can quickly adjust and compensate for the shaking of the bird's body and the disturbance of the environment, so that the bird's head remains in a high-frequency steady state, reflecting a phenomenon of "spatial immobility", thereby achieving the purpose of visual stability. At the same time, when some birds walk, the head is kept relatively still in space through the "holding state" of the "nodding" movement to maintain the stability of the head. This movement characteristic can be clearly observed from the motion trajectory diagram of pigeons walking. Birds can maintain head stability in natural movement modes such as take-off, landing, and swimming. In addition, birds can also reproduce this characteristic in a simulated test environment. This typical stabilization function of the bird's neck can provide useful inspiration for the design and development of continuum robotic arms. Summary of the invention

[0006] In order to solve the problem of how to achieve smooth movement, flexibility and high load of a continuum robotic arm in a confined or complex space, and combining the characteristics of a typical bird neck that can steadily and flexibly carry loads and operate a head that weighs far more than the neck itself to achieve various dexterous movement forms, the present invention imitates the typical movement form of the bird's neck and the characteristics of its joint structure, and proposes a bird-neck saddle-shaped bionic joint and a motion module and a bionic continuum robotic arm composed of the joint.

[0007] The technical solution adopted by the present invention is as follows:

[0008] A bionic joint imitating a bird's neck saddle shape, whose main structure is a cylinder imitating a bird's neck vertebra structure, and the bionic joint 14 is divided into an upper part 11 and a lower part 12; the upper part 11 is mainly composed of two small joint surfaces 111, 112 and a saddle-shaped protruding structure 113; the lower part 12 is mainly composed of a saddle-shaped groove structure 121 and a saddle-shaped joint plane 13;

[0009] When the two bionic joints 14 cooperate with each other, the two small joint surfaces 111 and 112 of the upper part 11 are symmetrically distributed on both sides of the bionic joint; the two small joint surfaces 111 and 112 of one bionic joint form an oblique relative sliding cooperation movement with the saddle-shaped joint plane 13 of the other bionic joint; the saddle-shaped groove structure 121 of the lower part 12 cooperates with the saddle-shaped protrusion structure 113 of the upper part 11 of the other bionic joint.

[0010] Furthermore, the curved surface of the saddle-shaped groove structure 121 is tangent to the curved surface of the saddle-shaped protrusion structure 113 .

[0011] A motion module composed of the bird-neck saddle-shaped bionic joint, the motion module mainly consists of two bionic joints 14, drive ropes 5, 6 and a motion motor, the two bionic joints have two through holes respectively at a distance of 3-5 mm from the connection in the four directions of front, back, left and right, the centers of the through holes are on a straight line, and the two bionic joints 14 are bound and fixed relative to the through holes by bionic ligament components; and two groups of reciprocating drive ropes 5, 6 are arranged inside the motion module, and the positions of the two groups of drive ropes 5, 6 are orthogonal to each other; the two groups of drive ropes 5, 6 are respectively wound around the shaft 8 of a motion motor, and the same drive rope is wound in opposite ways on the shaft 8 of the motion motor.

[0012] The bionic ligament component is preferably an elastic tie, a rubber band, a tension spring or a piano wire.

[0013] The bionic ligament component can be bound and fixed in a "parallel" or "cross" manner.

[0014] The driving ropes 5, 6 inside the motion module are constrained by the fixed structure 7-1.

[0015] Preferably, two threaded holes 7-2 are provided on the fixed structure 7-1, and the fixed structure 7-1 is connected to the bionic joint by screws. A limiting groove is provided on the fixed structure 7-1. When the screws are tightened, the limiting groove is used to limit the axial movement of the driving ropes 5 and 6, and to lock the driving ropes 5 and 6 and fix them together with the motion module structure, so that the driving force of the driving ropes 5 and 6 can be transmitted to the motion module.

[0016] A bionic continuum robotic arm is composed of a plurality of motion modules based on bird-neck saddle-shaped bionic joints. After the plurality of motion modules are connected, two sets of reciprocating drive ropes 5 and 6 are arranged between adjacent bionic joints and between one or more levels of bionic joints, and the drive ropes 5 and 6 are individually controlled by motion motors, thereby realizing control changes of various postures of the bionic robotic arm.

[0017] Beneficial effects of the present invention:

[0018] The bird neck saddle-shaped bionic joint proposed by the present invention is a special motion structure formed by connecting the front saddle-shaped joint with the two rear small joints. It can not only realize flexion movement in the ventral and dorsal directions, but also twisting movement. Compared with the traditional single-axis connection that can only realize rotational movement in a single direction, it has greater flexibility and operability in movement.

[0019] The single-stage motion module composed of the bird-neck saddle-shaped bionic joint proposed in the present invention is composed of two upper and lower bionic joints, and two or more single-stage motion modules constitute a bionic continuum robot arm (multi-stage motion module). The motion modules can be connected by cable ties, rubber bands, tension springs, piano wires, etc. to simulate the tension and pressure of tendons, ligaments and muscles. Adjacent segments or segments across one or more levels can be connected by the above flexible connection to achieve control changes in various postures of the bionic robot arm.

[0020] The present invention solves the above-mentioned defects of the current continuum robot arm by bionics of the saddle-shaped joint of the bird's neck, retaining the characteristics of smooth movement, flexibility and high load of the bird's neck. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0022] Figure 1 This is a CT image of the vertebrae of the goose neck;

[0023] Figure 2 The three-view diagram and axonometric diagram of the structure of the "saddle-shaped bionic joint" of Example 1 of the present invention;

[0024] Figure 3 A single-stage motion module diagram of the "saddle-shaped bionic joint" structure of Example 2 of the present invention;

[0025] Figure 4 It is a front view of a single-stage motion module of the "saddle-shaped bionic joint" structure of Example 2 of the present invention;

[0026] Figure 5 This is a rear view of a single-stage motion module of the "saddle-shaped bionic joint" structure of Example 2 of the present invention;

[0027] Figure 6 It is a left view of a single-stage motion module of the "saddle-shaped bionic joint" structure of Example 2 of the present invention;

[0028] Figure 7 It is a right view of a single-stage motion module of the "saddle-shaped bionic joint" structure of Example 2 of the present invention;

[0029] Figure 8 A partial view of the joint of the motion modules of the "saddle-shaped bionic joint" structure of Example 2 of the present invention

[0030] Fig. 9 This is a diagram showing the arrangement of the driving ropes of the "saddle-shaped bionic joint" structure of Example 2 of the present invention;

[0031] Fig.10This is a structural diagram of a driving rope fixing device of a "saddle-shaped bionic joint" structure according to Example 2 of the present invention;

[0032] Fig.11 This is a schematic diagram of the winding method of the driving rope of the "saddle-shaped bionic joint" structure on the motion motor shaft in Example 2 of the present invention;

[0033] Fig.12 It is a schematic diagram of the front view of a single-stage motion module "lateral bending and flexion" motion of the "saddle-shaped bionic joint" structure of Example 2 of the present invention;

[0034] Fig.13 It is a schematic diagram of the right side view of a single-stage motion module of the "saddle-shaped bionic joint" structure of Example 2 of the present invention in the "flexion and extension" motion;

[0035] Fig.14 It is a schematic bottom view of the "axial rotation" motion of a single-stage motion module of the "saddle-shaped bionic joint" structure of Example 2 of the present invention;

[0036] Fig.15 It is a structural diagram of the bionic continuum mechanical arm of the present invention. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present invention.

[0038] The present invention is based on the characteristics of the bird's neck joint structure, and the characteristics of the goose neck bone structure (such as Figure 1 As shown in the figure, the main motion connection mode is analyzed and extracted, which is mainly a three-point connection, including a ventral saddle-shaped joint structure and a pair of dorsal small joints. Based on the three-sided connection formed by the vertebrae of the goose neck, the present invention designs a "saddle-shaped bionic joint" structure, motion module and bionic continuum robot arm that imitates the bird neck.

[0039] Example 1

[0040] Firstly, the structure of a saddle-shaped bionic joint is explained.

[0041] See also Figure 2 The main structure of a single saddle-shaped bionic joint 14 is a cylinder that imitates the structure of a bird's cervical vertebra. The bionic joint 14 is divided into two parts: an upper part 11 and a lower part 12. The upper part 11 is mainly composed of two small joint surfaces 111 and 112 and a saddle-shaped protruding structure 113. The lower part 12 is mainly composed of a saddle-shaped groove structure 121 and a saddle-shaped joint plane 13.

[0042] When the two structures cooperate with each other, the two small joint surfaces 111 and 112 of the upper part 11 are symmetrically distributed on both sides of the bionic joint; the two small joint surfaces 111 and 112 of one bionic joint form an oblique relative sliding cooperation movement with the saddle-shaped joint plane 13 of the other bionic joint. The saddle-shaped groove structure 121 of the lower part 12 cooperates with the saddle-shaped protrusion structure 113 of the upper part 11 of the other bionic joint.

[0043] Due to the above-mentioned cooperation, this structure is different from the traditional single-axis connection and has more spatial freedom.

[0044] Example 2

[0045] The present invention can form a single-stage motion module with two bionic joints. The structure of a single-stage motion module will be analyzed below to explain its main coordination and driving methods.

[0046] See also Figure 3 The single-stage motion module in this embodiment is mainly composed of two bionic joints and a drive system. The two bionic joints have two through holes about 3-5 mm away from the connection in the four directions of front, back, left and right. The centers of the through holes are on a straight line. The two bionic joints are tied and fixed with elastic straps relative to the through holes. The tying method can be "parallel" or "cross". In addition, two sets of reciprocating drive ropes 5 and 6 are arranged inside the joint structure, and the positions of the two sets of drive ropes 5 and 6 are orthogonal to each other.

[0047] See also Figure 4 The elastic straps 3-1 and 3-2 are used to constrain the degrees of freedom of the front view parts of the two motion modules.

[0048] See also Figure 5 The elastic straps 3-3 and 3-4 are used to constrain the degrees of freedom of the rear view parts of the two motion modules.

[0049] See also Figure 6 , elastic straps 3-5 and 3-6 are used to constrain the degrees of freedom of the left-view parts of the two motion modules.

[0050] See also Figure 7 Elastic straps 3-7 and 3-8 are used to constrain the degrees of freedom of the right-view parts of the two motion modules.

[0051] See also Figure 8 The connection between the two motion modules is two tangent surfaces, which allows the two motion modules to have more movable space and less friction.

[0052] See also Fig. 9 The driving ropes arranged inside the motion module include a first driving rope 5 arranged horizontally in the center of the motion module and a second driving rope 6 arranged vertically.

[0053] See also Fig. 9 The driving ropes 5 and 6 inside the motion module are constrained by the fixed structure 7-1.

[0054] See also Fig.10 The fixing structure 7-1 is provided with two threaded holes 7-2, and the fixing structure 7-1 is connected to the bionic joint by screws. The fixing structure 7-1 is provided with a limit groove, and when the screw is tightened, the limit groove can not only limit the axial movement of the driving ropes 5 and 6, but also lock the driving ropes 5 and 6 and fix them together with the motion module structure, so that the driving force of the driving ropes 5 and 6 can be transmitted to the motion module.

[0055] The following will describe several motion forms of the motion module. In order to make the diagram clearer and easier to explain, the following figure omits the motion module connecting straps, drive ropes and rope fixing devices, leaving only two motion modules that move relative to each other. When describing the drive ropes, the rope numbers refer to Figure 2 and Fig. 9 .

[0056] See also Fig.11 The winding method of the drive ropes 5 and 6 on the shaft 8 of the motion motor should be as shown in the figure, with one end of a rope connected to 9-1 and the other end connected to 9-2; specifically, the winding method of the same drive rope on the motion module on the shaft 8 of the motion motor should be opposite; in this way, it can be ensured that the drive rope at one end is shortened and the drive rope at the other end is extended when the motion module moves.

[0057] See also Fig.12 and Fig. 9 , the motion module 2 is fixed, and when the first driving rope 5 passes Fig.11 After the motion motor is wound, the motion motor drives one side of the driving rope to shrink while the other side of the driving rope is lengthened. Since the shortened end of the driving rope is connected to the motion module 1, the driving rope will pull the motion module to move in the direction of 1-2-1 or 1-2-2, thereby realizing the "lateral bending" movement.

[0058] See also Fig.13 and Fig. 9 , the motion module 2 is fixed, and when the second drive rope 6 passes Fig.11 After the motion motor is wound, the motion motor rotates to shorten one side of the driving rope and lengthen the other side of the driving rope. Since the shortened end of the driving rope is connected to the motion module 1, the driving rope will pull the motion module to move in the direction of 1-3-1 or 1-3-2, thereby realizing the "flexion and extension" movement.

[0059] See also Fig.14 and Fig. 9 , the motion module 2 is fixed, when the first drive rope 5 and the second drive rope 6 pass Fig.11After the motion motor is wound, the two motors rotate simultaneously to drive the two driving ropes to shrink, while the other two driving ropes are longer. If the two motion modules are not restricted at this time, then one should move to the left front; but the two motion modules are flexibly connected by the cable tie 3, and the connection surface of the two motion modules is shown in FIG. Figure 8 The contact position is a smooth curved surface, which is tangent to each other and supports each other, but there is still a certain gap on the left and right. Due to the existence of these constraints, the two motion modules will not move one to the left front and the other to the right rear, but will twist along the central axis until the gaps on the left and right disappear, which is the maximum twisting degree. For its combined motion mode, see Fig.12 1-1-1 and 1-1-2, thus achieving "axial rotation" movement.

[0060] See also Fig.15 In the present invention, a multi-level motion module (i.e., a bionic continuum robotic arm) can be formed by connecting more bionic joints in series on the basis of a single-level motion module. After the multiple motion modules are connected, two sets of reciprocating drive ropes 5 and 6 are arranged between adjacent bionic joints and between one or more levels of bionic joints, and the drive ropes 5 and 6 are individually controlled by the motion motor, so that the control changes of various postures of the bionic robotic arm can be realized.

[0061] The above embodiments are only used to facilitate the description of the present scheme and structure, and are not intended to limit the present invention. Any simple changes and modifications that do not deviate from the content of the technical scheme of the present invention should be protected by the technical scheme of the present invention.

Claims

1. A motion module consisting of a bird-neck saddle-shaped bionic joint, It is characterized in that The motion module comprises two bionic joints (14), drive ropes (5, 6) and a motion motor. The two bionic joints are provided with two through holes at a distance of 3-5 mm from the connection in the four directions of front, back, left and right. The centers of the through holes are on a straight line. The two bionic joints (14) are bound and fixed relative to the through holes by bionic ligament components. Two groups of reciprocating drive ropes (5, 6) are arranged inside the motion module. The positions of the two groups of drive ropes (5, 6) are orthogonal to each other. The two groups of drive ropes (5, 6) are respectively wound around the shaft (8) of a motion motor, and the same drive rope (5, 6) is wound in opposite ways on the shaft (8) of the motion motor. The main structure of the bionic joint (14) is a cylinder that imitates the structure of a bird's cervical vertebra. The bionic joint (14) is divided into two parts: an upper part (11) and a lower part (12); the upper part (11) includes two small joint surfaces (111, 112) and a saddle-shaped protruding structure (113); the lower part (12) includes a saddle-shaped groove structure (121) and a saddle-shaped joint plane (13); When the two bionic joints (14) cooperate with each other, the two small joint surfaces (111, 112) of the upper part (11) are symmetrically distributed on both sides of the bionic joint; the two small joint surfaces (111, 112) of one bionic joint (14) and the saddle-shaped joint plane (13) of the other bionic joint (14) form an oblique relative sliding cooperation movement; the saddle-shaped groove structure (121) of the lower part (12) and the saddle-shaped protrusion structure (113) of the upper part (11) of the other bionic joint (14) cooperate with each other.

2. The motion module composed of the bird neck saddle-shaped bionic joint according to claim 1, It is characterized in that The curved surface of the saddle-shaped groove structure (121) is tangent to the curved surface of the saddle-shaped protrusion structure (113).

3. The motion module composed of the bird-neck saddle-shaped bionic joint according to claim 1, It is characterized in that The bionic ligament component is an elastic tie, a rubber band, a tension spring or a piano wire.

4. The motion module composed of the bird-neck saddle-shaped bionic joint according to claim 1, It is characterized in that The bionic ligament components are bound and fixed in a parallel or cross manner.

5. The motion module composed of the bird-neck saddle-shaped bionic joint according to claim 1, It is characterized in that The driving ropes (5, 6) inside the motion module are constrained by a fixed structure (7-1).

6. The motion module composed of the bird-neck saddle-shaped bionic joint according to claim 5, It is characterized in that The fixing structure (7-1) is provided with two threaded holes (7-2), and the fixing structure (7-1) is connected to the bionic joint (14) by means of screws; the fixing structure (7-1) is provided with a limiting groove, and when the screws are tightened, the limiting groove is used to limit the axial movement of the driving ropes (5, 6), and to lock the driving ropes (5, 6) and fix them together with the motion module structure, so that the driving force of the driving ropes (5, 6) can be transmitted to the motion module.

7. A bionic continuum mechanical arm composed of the motion module according to any one of claims 1 to 6, It is characterized in that The multiple motion modules are connected by bionic ligament components. After the multiple motion modules are connected, two sets of reciprocating drive ropes (5, 6) are arranged between adjacent bionic joints and between one or more levels of bionic joints, and the drive ropes (5, 6) are individually controlled by motion motors.

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