CN112936241A

CN112936241A - Snake-shaped robot

Info

Publication number: CN112936241A
Application number: CN202110373793.1A
Authority: CN
Inventors: 王宇; 逯云飞; 李亚鑫; 何梓玮; 周政辉
Original assignee: Southwest Petroleum University
Current assignee: Southwest Petroleum University
Priority date: 2021-04-07
Filing date: 2021-04-07
Publication date: 2021-06-11

Abstract

The invention provides a snake-shaped robot which comprises a plurality of joints, wherein a steering mechanism is arranged between every two adjacent groups of joints, the steering mechanism comprises a ball pin base assembly, two axial ends of the ball pin base assembly are respectively hinged with a group of ball pin rods, and each group of ball pin rods is respectively connected with a group of joints on the same side; two groups of connecting rods facing the ball pin base assembly are arranged in each two adjacent groups of joints, and each group of connecting rods is connected with a driving mechanism for driving the connecting rods to move in a telescopic manner; four groups of end heads are radially arranged on the side wall of the ball pin base assembly, the four groups of end heads are movably connected with the four groups of ball pin rods in a one-to-one correspondence manner, and in the four groups of end heads, two adjacent end heads are respectively connected with two groups of connecting rods in the same group of joints; in the snake-shaped robot, each joint can realize pitching and yawing motions, and the power mechanism adopts an industrial screw mechanism, so that the snake-shaped robot has stable, high-speed and powerful propelling effects, and can realize the effect of three-dimensional motion in a complex environment.

Description

Snake-shaped robot

Technical Field

The invention relates to the field of bionic robots, in particular to a snake-shaped robot.

Background

The inspiration of the snake-shaped robot comes from biological snakes, and the biological snakes have good maneuvering performance and can move on various complicated terrains; the snake-shaped robot imitates the design of a biological snake in shape and motion form, has higher degree of freedom and flexible and various motion forms, can exert unique advantages of the snake-shaped robot on specific occasions, such as unsuitability for detection and search and rescue work of manual operation occasions, in addition, in the aspect of military, the snake-shaped robot has the characteristics of compact structure, easy camouflage, high secrecy and the like, completes the task of investigation and patrol through self-carried image transmission equipment and the function of map construction, and can even carry ammunition in the future to complete the tasks of attack, explosion and the like; the size of the snake-shaped robot can be changed in a larger range, the tail end of the large-size snake-shaped robot carries tools for industrial production, and the microminiature snake-shaped robot can be used in the medical industry, and can be used for carrying out operations and the like.

The design structure is relatively simple, the control is convenient, and meanwhile, the design structure is a joint module with good space flexibility; however, most of the existing snake-shaped robots adopt parallel connection and orthogonal connection, and the connection modes have defects, for example, the axes of rotation pairs among modules of the snake-shaped robots connected in parallel are parallel to each other, so that the snake-shaped robots can only perform two-dimensional motion; for example, the chinese patent application with application number 202010853162.5 discloses a snake-like crawling robot, wherein adjacent joints of a snake body are connected by a steering mechanism, and the steering mechanism comprises a cross steering joint and a screw pair for driving the cross steering joint to steer, so that the movement of the snake body is relatively flexible; however, in any two adjacent joints, the first end and the second end of the cross steering joint which are opposite are connected with the tail of the previous joint, the third end and the fourth end of the cross steering joint which are opposite are connected with the head of the next joint, the previous joint is provided with a group of lead screw pairs which drive the cross steering joint to swing in a horizontal plane around the axis from the third end to the fourth end, the lead screw pairs on the next joint drive the cross steering joint to swing in a vertical plane around the axis from the first end to the second end, the cross steering joint only has two degrees of freedom, the steering range between the two adjacent joints is limited to swing in a horizontal plane and a vertical plane, and the movement range and the abundant degree of movement of the joints are limited.

Disclosure of Invention

The invention aims to overcome the defects of the background art and provide a snake-shaped robot.

The embodiment of the invention is realized by the following technical scheme:

a snake-shaped robot comprises a plurality of joints, wherein a steering mechanism is arranged between every two adjacent groups of joints and comprises a ball pin base assembly, two axial ends of the ball pin base assembly are respectively hinged with a group of ball pin rods, and each group of ball pin rods is respectively connected with a group of joints on the same side;

two groups of connecting rods facing the ball pin base assembly are arranged in each two adjacent groups of joints, and each group of connecting rods is connected with a driving mechanism for driving the connecting rods to move in a telescopic manner;

four groups of end heads are radially arranged on the side wall of the ball pin base assembly, the four groups of end heads are movably connected with the four groups of ball pin rods in a one-to-one correspondence mode, and in the four groups of end heads, two adjacent end heads are respectively connected with two groups of connecting rods in the same group of joints.

Further, the driving mechanism comprises a screw pair arranged in the joint, wherein a screw of the screw pair is parallel to the axial direction of the joint, and a sliding block of the screw pair is connected with the connecting rod so as to drive the connecting rod to move in a telescopic manner through the movement of the sliding block on the screw.

Furthermore, the first end of the connecting rod is hinged to the end head, and the second end of the connecting rod is hinged to the sliding block.

Furthermore, on a projection plane perpendicular to the axial direction of the ball pin seat assembly, included angles between any two adjacent groups of the four groups of the ends are all 90 degrees.

Furthermore, in the four groups of end heads, any two adjacent end heads are taken as a group of end head assemblies, the rest two adjacent end heads are taken as a second group of end head assemblies, and the two groups of end head assemblies are respectively arranged on two sides of the midpoint of the ball pin base assembly in the axial direction;

two groups of ends in the end assembly positioned on one side of the middle point are correspondingly connected with two groups of connecting rods in the joints on the same side one by one.

Furthermore, each group of joints is provided with a plurality of rollers.

Furthermore, the joint is cylindrical, and at least two groups of circular rings are rotatably sleeved on the outer wall of the joint; the at least two groups of circular rings are arranged along the axial direction of the joint, and a blocking mechanism is arranged on the joint and used for preventing each group of circular rings from moving along the axial direction of the joint; the outer ring surface of each group of rings is rotatably provided with a plurality of rollers.

Furthermore, a plurality of rotating pieces are arranged on the inner wall of the circular ring in a surrounding mode, and the rotating axis of each rotating piece is parallel to the axis of the circular ring.

Further, the joint includes a barrel, the drive mechanism disposed within the barrel;

two groups of first limiting rings are convexly arranged on the outer wall of the pipe barrel, two ends of the pipe barrel are respectively in threaded connection with a group of retaining rings, and a second limiting ring is convexly arranged on each group of retaining rings; the ring is sleeved on the outer wall of the pipe barrel between the first limiting ring and the second limiting ring at the same side; the blocking mechanism comprises the first limiting ring and a second limiting ring.

Furthermore, a plurality of fixing assemblies are uniformly arranged on the outer edge of the circular ring at intervals, a group of rollers is arranged between two adjacent groups of fixing assemblies, and two ends of each roller are respectively connected with one group of fixing assemblies in a rotating mode.

The technical scheme of the embodiment of the invention at least has the following advantages and beneficial effects:

in the snake-shaped robot, each joint can realize pitching and yawing motions, and the propeller adopts an industrial screw rod for propulsion, so that the snake-shaped robot has stable, high-speed and powerful propulsion effects, and can realize the effect of three-dimensional motion under a complex environment.

Drawings

FIG. 1 is a schematic structural view of a snake robot of the present invention;

FIG. 2 is an enlarged view of portion A of FIG. 1;

FIG. 3 is a schematic view of the structure of the steering mechanism of the snake-shaped robot of the present invention;

FIG. 4 is a schematic view of the joint structure of the snake robot of the present invention 1;

FIG. 5 is a schematic view of the joint structure of the snake robot of the present invention 2;

FIG. 6 is a schematic view of the joint structure of the snake robot of the present invention with the tube removed;

FIG. 7 is a schematic structural diagram of a roller assembly of the snake robot of the present invention;

FIG. 8 is a schematic view showing the operation control of the snake robot of the present invention;

icon: 1-joint, 10-pipe barrel, 100-slide block, 101-connecting rod, 102-guide rod, 103-motor, 104-screw rod, 105-first limiting ring, 106-connecting seat, 11-retaining ring, 110-second limiting ring, 2-steering mechanism, 20-ball pin seat component, 200-end, 21-ball pin rod, 3-roller component, 30-circular ring, 300-rotating component, 31-fixing component, 310-roller and 4-snake head.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1 to 7, the snake-shaped robot comprises a plurality of joints 1, a steering mechanism 2 is arranged between every two adjacent groups of joints 1, the joints 1 are connected in series through a steering assembly 2, and a snake head 4 is connected to the joint at the foremost end.

The steering mechanism 2 comprises a ball pin seat assembly 20, specifically, the ball pin seat assembly 20 comprises two groups of ball pin seats, the bottoms of the two groups of ball pin seats are connected and fixed together through screws, two axial ends of the ball pin seat assembly 20 are respectively hinged with a group of ball pin rods 21, each group of ball pin rods 21 is respectively connected with a group of joints 1 on the same side, specifically, the centers of the end parts of two ends of each group of joints 1 are respectively provided with a connecting seat 106, and the end parts of the ball pin rods 21 are connected with the connecting seats 106.

Referring to fig. 4, two groups of connecting rods 101 facing the ball pin seat assembly 20 are respectively arranged in the two adjacent groups of joints 1, each group of connecting rods 101 is connected with a driving mechanism for driving the connecting rods 101 to move in an extending and contracting manner, the driving mechanism comprises a screw pair arranged in the joint 1, a screw 104 of the screw pair is arranged in parallel to the axial direction of the joint 1, each group of screw 104 is connected with a group of motors 103, the motors 103 are arranged in the joint 1, a slider 100 in the screw pair is connected with the connecting rods 101, the connecting rods 101 are driven to move in an extending and contracting manner by the movement of the slider 100 on the screw 104, in addition, a guide rod 102 is arranged in the joint 1 in a direction parallel to the length direction of the screw 104, and the slider 100 is arranged on the guide rod 102 in a penetrating manner, so that.

Referring to fig. 2 and 3, four sets of end heads 200 are radially disposed on the side wall of the ball pin seat assembly 20, the four sets of end heads 200 are movably connected with the four sets of ball pin rods 21 in a one-to-one correspondence manner, and in the four sets of end heads 200, two adjacent sets of end heads 200 are respectively connected with two sets of connecting rods 101 in the same set of joints 1, and the remaining two adjacent sets of end heads 200 are respectively connected with two sets of connecting rods 101 in the other set of joints 1.

In some preferred embodiments, a first end of each set of links 101 is hinged to the end head 200, and a second end of each set of links 101 is hinged to the slider 100.

Based on the above structure, in order to connect the plurality of joints 1 in series, two sets of the connecting rods 101 are respectively disposed at two ends of each set of joint 1, and each set of the connecting rods 101 is respectively connected with one set of the driving mechanism, so that each set of joint 1 has four sets of the screw pairs and four sets of the motors 103.

In some preferred embodiments, on a projection plane perpendicular to the axial direction of the ball pin socket assembly 20, the included angle between any two adjacent sets of the four sets of the end heads 200 is 90 °, and referring to fig. 3, in the four sets of the end heads 200, any two adjacent sets of the end heads 200 are used as one set of end head assemblies, and the remaining two adjacent sets of the end heads 200 are used as a second set of end head assemblies, and the two sets of the end head assemblies are respectively arranged on two sides of the midpoint of the axial direction of the ball pin socket assembly 20;

referring to fig. 2, two sets of the end heads 200 in the end head assembly on the first side of the midpoint in the axial direction of the ball pin holder assembly 20 are connected to the two sets of the connecting rods 101 in the joint 1 on the first side in a one-to-one correspondence, and two sets of the end heads 200 in the end head assembly on the second side of the midpoint in the axial direction of the ball pin holder assembly 20 are connected to the two sets of the connecting rods 101 in the joint 1 on the second side in a one-to-one correspondence.

In addition, a plurality of rollers 310 are arranged on each group of joints 1.

Specifically, the joint 1 is cylindrical, at least two groups of rings 30 are rotatably sleeved on the outer wall of the joint 1, the two groups of rings 30 are arranged along the axial direction of the joint 1, that is, the number of the rings 30 can be set according to actual requirements, in this embodiment, the two groups of rings are provided, a blocking mechanism is provided on the joint 1 for preventing each group of rings 30 from moving along the axial direction of the joint 1, a plurality of rollers 310 are rotatably provided on the outer annular surface of each group of rings 30, the rings 30 can rotate around the joint 1, and the rings 30 are provided with a plurality of rollers 310 for enabling the pipe joint 1 to move more flexibly.

Specifically, referring to fig. 6, the interval is provided with a plurality of fixed subassemblies 31 uniformly on the ring 30 outer fringe, is provided with a set ofly between two sets of adjacent fixed subassemblies 31 gyro wheel 310, the both ends of gyro wheel 310 respectively with a set of fixed subassembly 31 rotates and is connected, and this design has not only reduced snake shape robot's the resistance of marcing, improves its movement resistance, and the straight face between two gyro wheels 310 has also increased the support area of snake body, has guaranteed that snake shape robot can stably berth and march.

In some preferred embodiments, in order to further improve the flexibility of the ring 30 and reduce the friction between the ring and the outer wall of the joint 1, a plurality of rotating members 300 are further arranged on the inner wall of the ring 30 in a surrounding manner, and the rotation axis of each rotating member 300 is parallel to the axis of the ring 30.

In some preferred embodiments, the joint 1 includes a barrel 10, and the driving mechanism is disposed in the barrel 10, where: in the present invention, the driving mechanism includes, but is not limited to, a rack and pinion driving mechanism, a linear module, and any one of the aforementioned screw pairs.

Two groups of first limiting rings 105 are convexly arranged on the outer wall of the pipe barrel 10, two ends of the pipe barrel 10 are respectively in threaded connection with a group of retaining rings 11, and specifically, the inner threads on the retaining rings 11 are screwed on the outer wall of the end part of the pipe barrel 10; a second limit ring 110 is convexly arranged on each group of retainer rings 11; the circular ring 30 is sleeved on the outer wall of the pipe barrel 10 between the first limiting ring 105 and the second limiting ring 110 on the same side; the blocking mechanism comprises the first stop collar 105 and the second stop collar 110, which allows the joint 1 to be easily disassembled and assembled.

In addition, the snake-shaped robot is a snake-shaped intelligent bionic robot based on machine vision, reinforcement learning and snake-shaped curves, the main content of the snake-shaped robot is divided into two parts, and the first part is a snake-shaped solid mechanical structure which is simple in design, high in efficiency and strong in pressure resistance; and secondly, designing a control program with good robustness by combining machine vision and reinforcement learning.

Through more intelligent control thought, more optimized mechanical structure, the control thought has combined advantages such as reinforcement study optimal control, accurate target detection of machine vision and intelligent navigation of route planning, makes it carry out level and smooth, stable marching according to the best route in the complex environment, and mechanical structure innovation embodies steering mechanism 2's design, every joint 1 can both realize every single move and yaw motion, and power unit adopts the industrial lead screw to impel, has possessed stable, high-speed and powerful propulsion effect.

Referring to fig. 8, in the aspect of controlling the snake-shaped robot, a controller and a sensor are mounted in the snake head 4 and each group of pipe joints 1, and if the controller is a raspberry type, the control module (hereinafter, referred to as a module) is arranged in each group of joints 1, and a gyroscope is arranged in each group of joints 1 to detect the snake-shaped posture, return the action parameters, and simultaneously stabilize the forward movement.

The snake-shaped motion control curve is highly fitted with the sine wave function, the written Python program is applied to the raspberry pie, the actions of the raspberry pie with the snake head 4 and the pipe joint 1 are converted into PWM signals, and then the motor 103 is controlled by the motor driving module, so that the robot is controlled to complete the motion effect in space.

Specifically, in this embodiment, the snake robot is composed of 8 modules, each module includes a motor driving module and four motors 103, which are a pitch motor set and a yaw motor set respectively. The first module is a host in the snake head 4, the modules in the other joints 1 are slaves, the host and the slaves are in Web _ Socket communication, the head of the snake head 4 is provided with a camera, images transmitted by the camera enter the host to carry out YOLO-V5 target detection so as to obtain environment information, the host obtains states and actions through reinforcement learning DDPG algorithm operation based on the collected information, and further obtains a whole action sequence of an optimal path, then the host sends corresponding actions of each module to the slaves through Web _ Socket communication according to the time sequence, and finally the raspberry of each module sends the actions to PWM signals, so that the motor driving modules in the modules control two motor sets at two ends of each joint 1, and the effect of actions in a three-dimensional space is achieved.

The raspberry group sends out PWM signal, and motor drive module control two motor groups, and the motion part of two motor group outputs via slider 100, and then drives connecting rod 101 to promote steering mechanism 2, and then realize the joint and rotate.

Static friction in the rotation process of the snake body generates an axial force, the component force of the axial force realizes the snake body to move forwards in a winding mode, and the roller is fixed in front of and behind the joint through the roller sleeve, so that the forward friction force is reduced.

Referring to fig. 8, specifically, each module includes a motor driving module and four motors 103, which are pitch and yaw motor sets respectively, the motor driving module in the module controls two motor sets to achieve an effect of acting in a three-dimensional space, when the module is not powered on, the slider 100 is located at a balanced position, the steering mechanism 2 does not deviate, when the single motor 103 is powered on with a forward or reverse voltage, the motor 103 pushes the slider 100 connected with the slider 103 to move forward or reverse, the slider 100 drives the connecting rod 101 to extend forward or retreat, and further pulls the steering mechanism 2 to rotate in a one-dimensional direction, and adjacent joints 1 are connected through the steering mechanism 2, so that maximum snake body deflection can be achieved.

The snakelike robot relies on the swing friction ground of health and obtains the power that advances, and gyro wheel 310 can produce great normal direction frictional force in order to prevent the production of the phenomenon of skidding as motion complementary unit, makes the resistance of motion diminish gradually simultaneously, improves snakelike robot's motion efficiency, and the design of gyro wheel 310 makes the robot have many ground connection area, therefore the robot has more stable three-dimensional motion ability.

The invention relates to an electrical system composition of a snake-walking bionic robot, which comprises a direct-current stabilized voltage power supply, a 78M05 voltage reduction module, an L298 speed reduction motor control module, a speed reduction motor and other components.

The raspberry pi controller of the robot is specifically ras berry _ zero _ wh, and is used for simultaneously controlling the swinging of the joint 1 and the snake head 4, and the different running time and rotating speed of the motor 103 are controlled by adjusting the duty ratio and delay time of the PWM wave output by the raspberry pi. And then the robot finishes the appointed action by coordinating the rotating speed and the action time sequence of each motor 103, thereby realizing the action similar to snake crawling, the action of snake crawling is a rhythm type movement similar to sine wave fluctuation, and when the robot moves on the land, the robot is pushed to move by the friction force between the point contacted with the ground of the snake-shaped robot and the ground. By controlling the rotation speed and the running time of the electric motor 103, the advancing or turning action of the robot can be controlled.

And a sensor is arranged on the snake head 4, a gyroscope is arranged on the snake body shutdown machine 1, and the parameters in the advancing process are returned in combination with reinforcement learning. In the test, the robot is found to be in high cooperation among the switches 1, the motion is stable and high-speed, and the gyroscope is carried, so that the robot is less interfered by the environment and has quick action response.

The special bionic robot manufactured by the snake-shaped robot according to the motion principle of the snake has the following advantages in a complex environment:

(1) the body is always kept attached to the ground in the movement process, and the movement of the body has stability due to the low gravity center walking mode;

(2) the forward power is obtained by friction by means of the swinging of the body, so that the device has certain automatic obstacle avoidance capability;

(3) the robot has the advantages that 39040can be formed by a long body and various gaits, the robot can pass through narrow space and partial gully, has rod-shaped object climbing capability, plays a role in exploration and operation in dangerous and complex environments, and has important application prospect.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a snake robot, includes a plurality of joints (1), all is equipped with steering mechanism (2), its characterized in that between every adjacent two sets of joints (1):

the steering mechanism (2) comprises a ball pin seat assembly (20), two axial ends of the ball pin seat assembly (20) are respectively hinged with a group of ball pin rods (21), and each group of ball pin rods (21) is respectively connected with a group of joints (1) on the same side;

two groups of connecting rods (101) facing the ball pin seat assembly (20) are respectively arranged in the two adjacent groups of joints (1), and each group of connecting rods (101) is connected with a driving mechanism for driving the connecting rods (101) to move in a telescopic manner;

four groups of end heads (200) are radially arranged on the side wall of the ball pin seat assembly (20), the four groups of end heads (200) are movably connected with the four groups of ball pin rods (21) in a one-to-one correspondence mode, and in the four groups of end heads (200), two adjacent groups of end heads (200) are respectively connected with two groups of connecting rods (101) in the same group of joints (1).

2. The serpentine robot of claim 1, wherein: the driving mechanism comprises a lead screw pair arranged in the joint (1), wherein a lead screw (104) of the lead screw pair is parallel to the axial direction of the joint (1), and a sliding block (100) of the lead screw pair is connected with the connecting rod (101) so as to drive the connecting rod (101) to move in a telescopic mode through the movement of the sliding block (100) on the lead screw (104).

3. The serpentine robot of claim 2, wherein: the first end of the connecting rod (101) is hinged to the end head (200), and the second end of the connecting rod (101) is hinged to the sliding block (100).

4. The serpentine robot of claim 1, wherein: on a projection plane perpendicular to the axial direction of the ball pin seat assembly (20), included angles between any two adjacent groups of the four groups of the end heads (200) are all 90 degrees.

5. The serpentine robot of claim 4, wherein: in the four groups of end heads (200), any two adjacent groups of end heads (200) are taken as one group of end head components, the rest two adjacent groups of end heads (200) are taken as a second group of end head components, and the two groups of end head components are respectively arranged on two sides of the midpoint of the ball pin base component (20) in the axial direction;

two groups of end heads (200) in the end head assembly positioned on one side of the middle point are correspondingly connected with two groups of connecting rods (101) in the same side joint (1).

6. The serpentine robot of any one of claims 1 to 5, wherein: each group of joints (1) is provided with a plurality of rollers (310).

7. The serpentine robot of claim 6, wherein: the joint (1) is cylindrical, and at least two groups of circular rings (30) are rotatably sleeved on the outer wall of the joint (1); the at least two groups of circular rings (30) are arranged along the axial direction of the joint (1), and a blocking mechanism is arranged on the joint (1) and used for preventing each group of circular rings (30) from moving along the axial direction of the joint (1); the outer ring surface of each group of circular rings (30) is rotatably provided with a plurality of rollers (310).

8. The serpentine robot of claim 7, wherein: the inner wall of the circular ring (30) is further provided with a plurality of rotating pieces (300) in a surrounding mode, and the rotating axis of each rotating piece (300) is parallel to the axis of the circular ring (30).

9. The serpentine robot of claim 7 or 8, wherein: the joint (1) comprises a tube (10), the drive mechanism being arranged within the tube (10);

two groups of first limiting rings (105) are convexly arranged on the outer wall of the pipe barrel (10), two ends of the pipe barrel (10) are respectively in threaded connection with a group of retaining rings (11), and a second limiting ring (110) is convexly arranged on each group of retaining rings (11); the circular ring (30) is sleeved on the outer wall of the pipe barrel (10) between the first limiting ring (105) and the second limiting ring (110) on the same side; the blocking mechanism comprises the first stop collar (105) and a second stop collar (110).

10. The serpentine robot of claim 7, wherein: a plurality of fixing assemblies (31) are uniformly arranged on the outer edge of the circular ring (30) at intervals, a group of rollers (310) is arranged between two adjacent groups of fixing assemblies (31), and two ends of each roller (310) are respectively and rotatably connected with one group of fixing assemblies (31).