A ball-jointed snake robot system and control method

Abstract

The application relates to the technical field, in particular to a ball hinge type snake robot system and a control method, which comprises a driving unit, a plurality of snake joint units installed on the driving end of the driving unit in sequence, and a control unit used for controlling the driving of the driving unit. The snake joint unit comprises a vertical rod and a disc installed on the top end of the vertical rod; the bottom end of the vertical rod is provided with a ball head, the top of the disc is provided with a ball seat, a plurality of rope holes are arranged on the disc, a rope segment is arranged in the rope hole, the rope segment is driven to stretch and contract by the driving unit, and a plurality of snake joint units are driven to move along a preset track. The patent can accurately control the stretching and contraction of the rope segment penetrating through each snake joint unit by the driving unit, so that the postures of the multiple snake joint units can be cooperatively adjusted, various complex motion tracks such as meandering, side shifting and rolling can be completed, flexible motion in a three-dimensional space can be realized, the snake robot can adaptively work in a narrow and rugged unstructured environment, and the application range and stability of the snake robot are expanded.

Description

Technical Field

[0001] This invention relates to the field of technology, specifically to a ball-joint snake robot system and its control method. Background Technology

[0002] Most snake robots in the present technology adopt a multi-drive unit driven system, that is, using series rigid joints or finite elastic units for bending motion. Such systems usually result in insufficient overall compliance and are prone to rigid impacts during movement, making it difficult to ensure smooth movement of the snake robot.

[0003] Furthermore, existing systems mostly rely on centralized control or simple distributed coordination, lacking the ability to accurately decouple and compensate for the coordinated motion of multiple joints in real time. When executing composite trajectories in three-dimensional space, the motion interference between the snake joint units is frequent, making it difficult to achieve accurate trajectory tracking and attitude synchronization. This leads to motion lag, jitter, or even instability in snake robots, resulting in existing snake robots lacking the ability to flexibly move laterally and roll in three-dimensional space. This further limits the adaptability of snake robots in narrow and unstructured environments and restricts the application scenarios of snake robots. Summary of the Invention

[0004] Given that existing snake robot systems suffer from insufficient overall compliance, are prone to rigid impacts during movement, and lack precise decoupling and real-time compensation capabilities for multi-joint coordinated motion, making it difficult to achieve accurate trajectory tracking and posture synchronization, and resulting in an inability to accurately adapt to narrow and unstructured environments, this invention provides a ball-joint snake robot system and control method. By controlling the drive unit through the control unit, several ball-joint snake joint units are driven to bend along a preset trajectory, enabling the snake robot to freely deflect in multiple directions. This allows the snake robot to adapt to working in narrow, rugged, and unstructured environments, expanding the application range and stability of snake robots.

[0005] The present invention provides a ball-joint snake robot system, comprising: a drive unit, a plurality of snake joint units sequentially mounted on the drive end of the drive unit, and a control unit for controlling the drive unit.

[0006] The snake joint unit includes: a vertical rod and a disc installed at the top of the vertical rod; the bottom end of the vertical rod is provided with a ball head, the top of the disc is provided with a ball seat, the disc is provided with a plurality of rope holes, and rope segments are passed through the rope holes. The drive unit drives the rope segments to extend and retract, thereby driving a plurality of snake joint units to move along a preset trajectory.

[0007] Furthermore, the control unit includes:

[0008] The data acquisition module is used to collect data.

[0009] The processing module is electrically connected to the acquisition module and is used to process the real-time signals acquired by the acquisition module.

[0010] A calculation module, electrically connected to the processing module, is used to calculate the data processed by the processing module.

[0011] The output module is electrically connected to the calculation module and is used to output the data calculated by the calculation module to the drive unit to drive the movement of several snake joint units.

[0012] The present invention also provides a control method for a ball-joint snake robot system, comprising:

[0013] Collect the initial position information of the snake robot;

[0014] Based on the collected initial position information and initial commands, the motion trajectory is planned using a comprehensive snake-like calculation model;

[0015] The motion commands are input into the control device to control the snake robot to move along the set trajectory;

[0016] The snake robot's trajectory is updated and adjusted in real time by executing the feedback model.

[0017] The initial position information includes: disk thickness, distance from the center of the adjacent disk to the ball seat, distance from the ball seat to the center of the next disk, distance from the center of the ball seat to the first ball head, and distance from the center of the disk to the center of the rope hole.

[0018] Furthermore, the snake-like computational model includes:

[0019] Based on the initial position information of the snake robot, set the origin coordinate disk;

[0020] The initial absolute pose parameters of the snake robot are calculated and obtained through a matrix transformation model.

[0021] By combining the initial absolute pose parameters of the snake robot, setting the axial coordinate input, and obtaining the initial pose vector;

[0022] Based on the initial input command, obtain the motion pose parameters;

[0023] The motion trajectory of the snake robot is obtained by smoothing the trajectory through interpolation.

[0024] Furthermore, the matrix transformation model includes: a first transformation matrix, a second transformation matrix, and a third transformation matrix;

[0025] The first transformation matrix represents the translational transformation relationship from the center of the disk to the ball head mounted on it;

[0026] The second transformation matrix represents the relationship between the spacing between the centers of adjacent disks;

[0027] The third transformation matrix represents the distance transformation relationship from the sphere head to the next adjacent disk.

[0028] Furthermore, the initial position parameters include:

[0029] The radius distance from the center of the disc to the center of the rope hole, the circumferential angle between adjacent rope holes, the distance between the centers of the ball seats of adjacent discs, the distance from the center of the disc to the ball head installed in the ball seat, and the initial length of the rope segment threaded in each ball joint segment.

[0030] Furthermore, the initial absolute pose parameters of the integrated snake robot, setting the axial coordinate input, and obtaining the initial pose vector include:

[0031] Obtain the unit vector by inputting the axial coordinate.

[0032] Using unit vectors, the initial positions of each disk, the ball head, and the rope segment are calculated under the initial absolute pose, and the expected orientation vector of the ball head is obtained by comprehensive calculation.

[0033] By comprehensively adjusting the attitude model, the coordinates of each disk, ball head, and rope segment are updated in real time.

[0034] Furthermore, the adjusted posture model includes:

[0035] Construct a rotation matrix based on the unit vector, and obtain the motion posture of the ball head in the rotation matrix by combining the initial position of the ball head;

[0036] The rotation matrix is ​​updated in real time according to the preset trajectory to obtain the real-time position data of the disk, ball head, and rope segment;

[0037] The deformation trajectory of each snake joint segment is obtained through comprehensive calculation.

[0038] Furthermore, the real-time execution feedback model includes:

[0039] Real-time updates of disk coordinates, ball head coordinates, and rope segment coordinates;

[0040] The number of rotations and movements required to reach the coordinates is calculated comprehensively to obtain the final real-time trajectory of the snake robot.

[0041] When the snake robot changes its trajectory in real time, the snake joint unit updates the motion trajectory data in real time.

[0042] When a change in trajectory is required, the real-time control direction is changed by inputting a new command with the opposite value, thereby generating a new motion trajectory.

[0043] Compared with the prior art, the beneficial effects of the present invention are:

[0044] 1. This invention patent uses a control unit to control a drive unit to drive several ball-joint snake joint units to bend along a preset trajectory, enabling the snake robot to freely deflect in multiple directions. Specifically, the drive unit precisely controls the extension and retraction of the rope segments passing through each snake joint unit, thereby coordinating the posture of multiple snake joint units to complete various complex motion trajectories such as meandering, lateral movement, and rolling, achieving flexible movement in three-dimensional space. This makes the snake robot's overall movement smooth and highly adaptable, especially in narrow, rugged, and unstructured environments. It can adaptably traverse pipes, explore ruins, or perform detection tasks in confined spaces, expanding the application scope and stability of snake robots.

[0045] 2. The control method of this patented invention improves the motion accuracy, environmental adaptability, and operational reliability of the ball-joint snake robot system by constructing a complete closed loop from initial modeling and trajectory planning to real-time feedback, and possesses real-time dynamic adjustment capabilities. While executing preset commands, this patented system continuously monitors the actual state of the snake robot and its interaction with the environment, compares and calculates the expected trajectory with the actual pose in real time, and can input supplementary commands in real time for position adjustment, optimizing the preset trajectory in real time. This real-time closed-loop control enables the snake robot to cope with complex and unstructured dynamic environments. Whether encountering sudden obstacles in a pipeline or needing to adjust its posture immediately during exploration, the system ensures smooth, stable, and precise motion, expanding the practical value of snake robots in precision operations and autonomous exploration.

[0046] It should be understood that the description in the Summary of the Invention is not intended to limit the key or essential features of the embodiments of the present invention, nor is it intended to restrict the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0047] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0048] Figure 1 This is an overall diagram of a ball-joint snake robot system.

[0049] Figure 2 This is an overall diagram of the snake joint unit.

[0050] Figure 3 This is a structural diagram of the control unit.

[0051] Figure 4 This is a flowchart of the control method for a ball-joint snake robot system.

[0052] Figure 5This is a flowchart of the snake-shaped computation model.

[0053] Figure 6 This is a schematic diagram of the motion trajectory of a ball-joint snake robot.

[0054] The diagram is labeled as follows: 1. Drive unit; 2. Snake joint unit; 21. Vertical rod; 22. Disc; 23. Ball head; 24. Ball seat; 25. Rope hole;

[0055] 31. Acquisition module; 32. Processing module; 33. Calculation module; 34. Output module. Detailed Implementation

[0056] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0057] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly set on the other component; when a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to the other component.

[0058] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0059] Please refer to Figures 1-6 The present invention provides a ball-joint snake robot system, comprising: a drive unit 1, a plurality of snake joint units 2 sequentially installed on the drive end of the drive unit 1, and a control unit for controlling the drive unit 1.

[0060] The snake joint unit 2 includes: a vertical rod 21 and a disc 22 installed at the top of the vertical rod 21; a ball head 23 is provided at the bottom of the vertical rod 21, a ball seat 24 is provided at the top of the disc 22, and a plurality of rope holes 25 are provided on the disc 22. Rope segments are passed through the rope holes 25. The rope segments are driven to extend and retract by the drive unit 1, thereby driving a plurality of snake joint units 2 to move along a preset trajectory.

[0061] To further explain, such as Figure 3As shown, the control unit includes: a data acquisition module 31, a processing module 32, a calculation module 33, and an output module 34. The data acquisition module 31 is used to acquire data; the processing module 32 is electrically connected to the data acquisition module 31 and is used to process the real-time signals acquired by the data acquisition module 31; the calculation module 33 is electrically connected to the processing module 32 and is used to calculate the data processed by the processing module 32; the output module 34 is electrically connected to the calculation module 33 and is used to output the data calculated by the calculation module 33 to the drive unit 1 to drive the movement of several snake joint units 2.

[0062] In this embodiment, the control unit controls the drive unit 1 to drive several ball-joint snake joint units 2 to bend along a preset trajectory, realizing the free deflection of the snake robot in multiple directions. Specifically, the drive unit 1 precisely controls the extension and retraction of the rope segment passing through each snake joint unit, thereby coordinating the posture of multiple snake joint units 2 to complete various complex motion trajectories such as meandering, lateral movement, and rolling, realizing flexible movement in three-dimensional space. This makes the snake robot's overall movement smooth and highly adaptable, especially able to work in narrow, rugged, and unstructured environments. It can adaptably cross pipes, explore ruins, or perform detection tasks in confined spaces, expanding the application range and stability of the snake robot.

[0063] In this embodiment, several snake joint units 2 are flexibly bent with multiple degrees of freedom by embedding ball heads 23 into ball seats 24 and controlling the drive unit 1 through the control unit to pull several rope segments. During the movement, pulling the rope segments can accurately transmit operation commands, allowing the snake joint unit 2 connected to the current rope segment to rotate completely without constraint relative to the adjacent snake joint unit 2. The control unit controls the maximum rotation angle, thereby achieving continuous and smooth posture adjustment in three-dimensional space. This allows the snake robot to complete large-arc turns as well as local fine bending, making it suitable for performing tasks such as passage, obstacle avoidance, and precise operation in narrow, complex, and unstructured spaces, thus improving the adaptability and motion performance of the snake robot.

[0064] Furthermore, the acquisition module 31 acquires motion posture information in real time and transmits the information to the processing module 32 for data processing. The processing module 32 transmits the processed posture data to the calculation module 33 for optimization calculation. Finally, the output module 34 outputs the calculated trajectory to control each snake joint unit 2 to move along a predetermined trajectory.

[0065] like Figures 4-6 As shown, the present invention also provides a control method for a ball-joint snake robot system, comprising:

[0066] Collect the initial position information of the snake robot.

[0067] Based on the collected initial position information and initial commands, a comprehensive snake-like calculation model is used to plan the motion trajectory.

[0068] The motion commands are input into the control device to control the snake robot to move along the set trajectory.

[0069] The snake robot's trajectory is updated and adjusted in real time by executing the feedback model.

[0070] Furthermore, the initial position information includes: the thickness of disk 22, the distance from the center of the adjacent disk 22 to the ball seat 24, the distance from the ball seat 24 to the center of the next disk 22, the distance from the center of the ball seat 24 to the first ball head 23, and the distance from the center of disk 22 to the center of the rope hole 25.

[0071] This embodiment improves the motion accuracy, environmental adaptability, and operational reliability of the ball-joint snake robot system by constructing a complete closed loop from initial modeling and trajectory planning to real-time feedback, and possesses real-time dynamic adjustment capabilities. While executing preset commands, this patented system continuously monitors the snake robot's actual state and environmental interaction information, compares and calculates the expected trajectory with the actual pose in real time, and can input supplementary commands in real time for position adjustment, optimizing the preset trajectory in real time. This real-time closed-loop control enables the snake robot to cope with complex and unstructured dynamic environments. Whether encountering sudden obstacles in a pipeline or needing to adjust its posture immediately during exploration, the system ensures smooth, stable, and precise motion, expanding the practical value of snake robots in precision operations and autonomous exploration.

[0072] In this embodiment, a handle is selected as the input control device. Motion commands are input into the handle, the snake joint unit 2 is set to have h segments, and a command variable is set to represent the Fth segment of snake joint unit 2 to be controlled, with an initial value of 1. Each press of the handle button increments the command variable by 1, thus controlling the next segment of snake joint unit 2. When F=1, the first segment of snake joint unit 2 is controlled to extend and retract; when h<F<1, the posture of the current snake joint unit 2 relative to the previous snake joint unit 2 is controlled, i.e., the posture adjustment of the current disk 22 relative to the previous disk 22 is controlled; when F=h, it indicates that the position adjustment control of h segments of snake joint unit 2 has been completed, i.e., the posture setting of h disks 22 has been completed.

[0073] When controlling the motion of the snake-like robot, pushing the joystick forward extends several snake joint units 2 forward; pushing the joystick backward retracts these units. During the extension and retraction of the snake joints, the disks 22, ball heads 23, and rope segments all move along preset trajectories. If a single snake joint unit 2 is adjusted, the entire motion trajectory needs to be updated, and the motion trajectories of each disk 22, ball head 23, and rope segment must be recalculated based on the snake-like calculation model, thus generating a new snake robot motion trajectory.

[0074] To further explain, the snake-like computational model includes:

[0075] Based on the initial position information of the snake robot, set the origin coordinate disk.

[0076] The initial absolute pose parameters of the snake robot are calculated using a matrix transformation model.

[0077] By combining the initial absolute pose parameters of the snake robot and setting the axial coordinate input, the initial pose vector is obtained.

[0078] Based on the initial input command, obtain the motion pose parameters.

[0079] The motion trajectory of the snake robot is obtained by smoothing the trajectory through interpolation.

[0080] To further explain, taking the initial position of the snake robot as the origin plane, the initial origin coordinates of each snake joint unit 2 are set, and the origin position coordinates of the disk 22, ball head 23, and rope segment within each snake joint unit 2 are obtained. The positional relationship of each snake joint unit 2 is set through a matrix transformation model and represented by a model matrix function, thereby obtaining the initial absolute pose parameters of each snake joint unit 2 of the snake robot. The initial pose vector of each snake joint unit 2 of the snake robot is obtained through axial coordinate transformation. The endpoint plane that the snake robot needs to reach is set, the initial command to reach the plane is input, and the motion pose parameters of each snake joint unit needing to reach the plane are obtained. The trajectory is smoothed using interpolation, and finally, the initial motion trajectory of the snake robot from the initial plane to the endpoint plane is obtained.

[0081] To further clarify, the matrix transformation model includes: a first transformation matrix, a second transformation matrix, and a third transformation matrix.

[0082] The first transformation matrix represents the translational transformation relationship from the center of disk 22 to the ball head 23 mounted on it.

[0083] The second transformation matrix represents the relationship between the distances between the centers of adjacent disks 22.

[0084] The third transformation matrix represents the distance transformation relationship between the ball head 23 and the adjacent next disk 22.

[0085] Furthermore, the initial position parameters include: the radius distance from the center of the disc 22 to the center of the rope hole 25, the circumferential angle between adjacent rope holes 25, the center distance between the ball seats 24 of adjacent discs 22, the distance from the center of the disc 22 to the ball head 23 installed in the ball seat 24, and the initial length of the rope segment threaded in each ball joint segment.

[0086] In this embodiment, by combining the initial absolute pose parameters of the snake robot and setting the axial coordinate input, the initial pose vector is obtained, including:

[0087] The unit vector is obtained by inputting the axial coordinate.

[0088] Using unit vectors, the initial positions of each disk 22, the ball head 23, and the rope segment are calculated under the initial absolute pose, and the expected orientation vector of the ball head 23 is obtained by comprehensive calculation.

[0089] By comprehensively adjusting the attitude model, the coordinates of each disk 22, ball head 23, and rope segment are updated in real time.

[0090] To further explain, the axial coordinate input value is set. , And through the formula Get the unit vector To filter out jitter, when the absolute value of the axis value is less than 0.1, , It needs to be scaled adaptively.

[0091] Adjusting the attitude model includes:

[0092] Construct a rotation matrix based on the unit vector, and obtain the motion posture of the ball head 23 in the rotation matrix by combining the initial position of the ball head 23.

[0093] The rotation matrix is ​​updated in real time according to the preset trajectory to obtain the real-time position data of disk 22, ball head 23, and rope segment.

[0094] The deformation trajectory of each snake joint segment is obtained through comprehensive calculation.

[0095] To further explain, the initial ball head 23 pose of the h-th disk 22 is multiplied by a factor... The generated rotation matrix changes the orientation of the ball head 23 of the h-th disk 22 relative to the previous disk 22. The relative transformation matrix between all disks 22 is updated in real time, and the positions of all ball heads 23 and rope holes 25 in the coordinate system are recalculated. The current length of each rope segment is also calculated in real time. Finally, the data is synthesized and presented in a 3D view. Therefore, the corresponding rotational deformation trajectory of the h-segment snake joint relative to the unit of the snake robot can be calculated, and the deformation process of the snake robot is provided with real-time feedback through a visual interface.

[0096] If the motion posture of a snake joint unit 2 needs to be changed during the movement, it means that the current input is the opposite of the previous input. Therefore, the opposite motion to the previous input needs to be performed. The trajectory can be selected and modified adaptively through the preset trajectory list to adjust the offset angle, offset value, and extension direction of each snake joint unit 2 in the preset trajectory. Furthermore, the position and rotation angle of each disk 22, ball head 23, and rope segment can be adjusted to generate a new snake robot motion trajectory.

[0097] When the extension / retraction direction changes upon reaching the h-th disk 22, it indicates that the previous extension / retraction input is opposite to the current one. If the current command is retraction, the trajectory stores the axial coordinates of the next serpentine joint unit disk 22 in the current posture, and simultaneously sets the current disk 22 and the previous disk 22 to an axially vertical state. Then, the ball head 23 rotates to the maximum displacement, controlling the current serpentine joint unit 2 to be in a fully retracted state.

[0098] If the current command is to extend, the trajectory stores the axial coordinates of the serpentine joint unit disk 22 in the current posture, and at the same time sets the current disk 22 and the previous disk 22 to be axially parallel. Then the ball head 23 rotates to the maximum displacement in the opposite direction, controls the current serpentine joint unit 2 to be in the extended state, and constructs the corresponding trajectory from the tail end of the current posture.

[0099] After changing the motion posture of the h-th snake joint unit 2, the posture of all snake joint units 2 after the current snake joint unit 2 needs to be adjusted. Therefore, it is necessary to comprehensively calculate the position and rotation angle of all disks 22, ball heads 23 and rope segments based on the adjusted posture model, that is, to re-determine the deformation trajectory of the snake robot. The transformation relationship between each parameter must satisfy the constraints of the first transformation matrix, the second transformation matrix and the third transformation matrix.

[0100] Throughout the control process, the program continuously initializes the 3D graphics window, dynamically displaying the snake robot's motion trajectory. Specifically, the positions of the disk 22, ball head 23, rope hole 25, and rope segment of snake joint unit 2 are smoothly drawn sequentially. Therefore, the 3D graphics window updates in real time with each change in the snake robot's posture caused by the motion trajectory, or after each extension / retraction movement, providing visual feedback on the changes in the snake robot. Furthermore, the 3D graphics window displays the real-time length of the rope segment and the currently operating snake joint unit 2 on the screen, helping the operator understand the current state.

[0101] When the user operates the joystick to change or edit the motion trajectory, the motion pose parameters of each snake joint unit 2 will be updated again through the snake calculation model. That is, the new positions of the disk 22, ball head 23, rope segment, and matrix transformation model are calculated in real time to ensure that physical constraints are met and the state update is consistent with physical laws.

[0102] When operating sequentially to the last disk 22, a smooth transition process is performed on the attitude changes of all disks 22. That is, the number of rotation and movement steps required for the transition between adjacent states of each disk 22 is calculated, and an interpolation angle is generated. The attitude of each disk 22 is synchronously rotated through the interpolation method, so that a smooth change trajectory model can be output, realizing a smooth and continuous attitude transition of each snake joint unit 2 of the snake robot, and avoiding the impact caused by sudden jumps.

[0103] To further explain, the real-time execution feedback model includes:

[0104] The coordinates of disk 22, ball head 23, and rope segment are updated in real time.

[0105] The number of rotations and movements required to reach the coordinates is calculated comprehensively to obtain the final real-time trajectory of the snake robot.

[0106] When the snake robot changes its trajectory in real time, the snake joint unit 2 updates the motion trajectory data in real time.

[0107] When a change in trajectory is required, the real-time control direction is changed by inputting a new command with the opposite value, thereby generating a new motion trajectory.

[0108] To further explain, a virtual motion mapping space is first constructed by dynamically updating the coordinates of disk 22, ball head 23, and rope segment in real time, enabling the control system to continuously track the precise spatial posture of the snake robot. Based on this, the number of rotations and movements required to reach the target position is comprehensively calculated, thereby planning a smooth and achievable real-time motion trajectory and realizing adaptive motion control.

[0109] During trajectory execution, the system continuously monitors the motion status of each snake joint unit 2 and updates the trajectory data in real time, forming a closed-loop mode of perception feedback. This enables the snake robot to flexibly cope with complex environments, and even when encountering obstacles or uneven ground, it can dynamically adjust its movements to maintain motion stability and directional accuracy.

[0110] When a change in trajectory or direction is needed, the operator must input a new command with the opposite value, and the model can respond quickly, immediately generating a new, reversed or corrected trajectory. This not only improves the sensitivity and intuitiveness of control but also enables the snake robot to avoid obstacles and reorient itself in a timely manner when performing tasks such as search and rescue and exploration, enhancing its adaptability and operational reliability in unknown or dynamic environments.

[0111] It should be understood that the specific embodiments described above are for illustrative purposes only and are not intended to limit the scope of the invention. Obvious variations or modifications derived from the spirit of the invention are still within the protection scope of the invention.

Claims

1. A ball-joint type snake robot system, characterized in that, include: The drive unit (1), a plurality of snake joint units (2) sequentially installed on the drive end of the drive unit (1), and a control unit for controlling the drive unit (1) to drive; The snake joint unit (2) includes: a vertical rod (21) and a disc (22) installed at the top of the vertical rod (21); a ball head (23) is provided at the bottom end of the vertical rod (21), a ball seat (24) is provided at the top of the disc (22), and a plurality of rope holes (25) are provided on the disc (22). Rope segments are passed through the rope holes (25), and the rope segments are driven to extend and retract by the drive unit (1), thereby driving a plurality of snake joint units (2) to move along a preset trajectory.

2. The ball-joint type snake robot system according to claim 1, characterized in that, The control unit includes: The data acquisition module (31) is used to acquire data; The processing module (32) is electrically connected to the acquisition module (31) and is used to process the real-time signals acquired by the acquisition module (31); The calculation module (33) is electrically connected to the processing module (32) and is used to calculate the data processed by the processing module (32); The output module (34) is electrically connected to the calculation module (33) and is used to output the data calculated by the calculation module (33) to the drive unit (1) to drive the movement of several snake joint units (2).

3. The control method for the ball-joint snake robot system according to claim 1, characterized in that, include: Collect the initial position information of the snake robot; Based on the collected initial position information and initial commands, the motion trajectory is planned using a comprehensive snake-like calculation model; The motion commands are input into the control device to control the snake robot to move along the set trajectory; The snake robot's trajectory is updated and adjusted in real time by executing the feedback model in real time. The initial position information includes: the thickness of the disk (22), the distance from the center of the adjacent disk (22) to the ball seat (24), the distance from the ball seat (24) to the center of the next disk (22), the distance from the center of the ball seat (24) to the first ball head (23), and the distance from the center of the disk (22) to the center of the rope hole (25).

4. The ball-joint snake robot control method according to claim 3, characterized in that, The snake-like calculation model includes: Based on the initial position information of the snake robot, set the origin coordinate disk; The initial absolute pose parameters of the snake robot are calculated and obtained through a matrix transformation model. By combining the initial absolute pose parameters of the snake robot, setting the axial coordinate input, and obtaining the initial pose vector; Based on the initial input command, obtain the motion pose parameters; The motion trajectory of the snake robot is obtained by smoothing the trajectory through interpolation.

5. The ball-joint snake robot control method according to claim 4, characterized in that, The matrix transformation model includes: a first transformation matrix, a second transformation matrix, and a third transformation matrix; The first transformation matrix is ​​the translation transformation relationship from the center of the disk (22) to the ball head (23) mounted on it; The second transformation matrix represents the relationship between the spacing between the centers of adjacent disks (22); The third transformation matrix is ​​the distance transformation relationship between the ball head (23) and the next adjacent disk (22).

6. The ball-joint snake robot control method according to claim 4, characterized in that, The initial position parameters include: The radius distance from the center of the disc (22) to the center of the rope hole (25), the circumferential angle between adjacent rope holes (25), the center distance between the ball seats (24) of adjacent discs (22), the distance from the center of the disc (22) to the ball head (23) installed in the ball seat (24), and the initial length of the rope segment threaded in each snake joint unit (2).

7. The ball-joint snake robot control method according to claim 4, characterized in that, The initial absolute pose parameters of the integrated snake robot are set, and the initial pose vector is obtained by setting the axial coordinate input, including: Obtain the unit vector by inputting the axial coordinate. Using unit vectors, the initial positions of each disk (22), the ball head (23), and the rope segment are calculated under the initial absolute pose, and the expected orientation vector of the ball head (23) is obtained by comprehensive calculation. By comprehensively adjusting the posture model, the coordinates of each disk (22), ball head (23), and rope segment are updated in real time.

8. The control method for a ball-joint snake robot according to claim 7, characterized in that, The attitude adjustment model includes: Construct a rotation matrix based on the unit vector, and obtain the motion posture of the ball head (23) in the rotation matrix by combining the initial position of the ball head (23); The rotation matrix is ​​updated in real time according to the preset trajectory to obtain the real-time position data of the disk (22), ball head (23), and rope segment; The deformation trajectory of each snake joint segment is obtained through comprehensive calculation.

9. The ball-joint snake robot control method according to claim 3, characterized in that, The real-time execution feedback model includes: The coordinates of the disk (22), the ball head (23), and the rope segment are updated in real time. The number of rotations and movements required to reach the coordinates is calculated comprehensively to obtain the final real-time trajectory of the snake robot. When the snake robot changes its trajectory in real time, the snake joint unit (2) updates the motion trajectory data in real time. When a change in trajectory is required, the real-time control direction is changed by inputting a new command with the opposite value, thereby generating a new motion trajectory.

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