A caterpillar angle adjusting mechanism and method of a double caterpillar wall-climbing robot

Abstract

The invention relates to a kind of double caterpillar wall-climbing robot caterpillar angle adjusting mechanism and method, which comprises fixed frame, drive assembly, rotary connection assembly and caterpillar assembly, the drive assembly is fixed on fixed frame, the rotary connection assembly can be rotatably fixed on fixed frame, the drive assembly is used to drive rotary connection assembly rotation, the caterpillar assembly connects rotary connection assembly, the rotary center axis of rotary connection assembly is parallel with the direction of caterpillar assembly movement, the rotary connection assembly is used to drive caterpillar assembly rotation, the caterpillar assembly includes caterpillar and adsorption assembly, the adsorption assembly is symmetrically arranged on the both sides of caterpillar, and the lower plane of adsorption assembly and the lower plane of caterpillar are parallel to each other.Compared with prior art, the invention has the advantages of strong stability and safety.

Description

Technical Field

[0001] This invention relates to the field of climbing robot technology, and in particular to a track angle adjustment mechanism and method for a dual-track wall-climbing robot. Background Technology

[0002] Wall-climbing robots are automated robots capable of climbing walls and completing tasks; also known as wall-mounted mobile robots, they possess two basic functions: adhesion and movement. Adhesion allows the robot to attach to the wall surface, ensuring stable operation. Existing wall-climbing robots are widely used in industries such as pipeline flaw detection and inspection, grinding and welding, building cleaning and painting, nuclear industry product inspection and thickness measurement, fire fighting, and shipbuilding. They can replace manual labor in some high-risk or harsh environment tasks, improving operational safety.

[0003] Existing heavy-load wall-climbing robots can perform complex movements such as turning in place on a plane, but they cannot guarantee good mobility on the inner wall of cylindrical pipes, thus failing to meet usage requirements.

[0004] For example, Chinese patent CN211893445U discloses a wall-climbing robot, which includes a vehicle body, a track assembly, an angle adjustment assembly, a drive assembly, and a locking assembly. The track assembly is rotatably connected to both sides of the vehicle body. The angle adjustment assembly includes a rotating shaft and two support rods. The two support rods are rotatably connected to the rotating shaft. One end of each support rod is rotatably connected to the corresponding track assembly. The drive assembly is set on the vehicle body. The other end of each support rod is connected to the output end of the drive assembly. The drive assembly is configured to make the two support rods form a preset angle.

[0005] However, the above-mentioned wall-climbing robot mechanism uses a slide rail and linkage mechanism, which has a relatively loose structure, large slide rail gaps, poor stability, high processing difficulty, high requirements for slide rail materials, poor precision, and poor load-bearing capacity. As a result, the robot has poor stability during movement. On the other hand, it uses the lever principle to adjust the track angle, and the two sides share a common fulcrum, which places high demands on the load-bearing capacity and requirements of the fulcrum.

[0006] Because pipelines contain obstacles such as welds, expansion joints, and weld slag adhering to the pipe walls, achieving flexible robot movement within the pipeline requires ensuring that the distance between each position on every track assembly and the pipe wall is sufficiently large in any pose. Otherwise, the robot may become stuck and unable to move further due to insufficient distance between a certain point on a track assembly and the wall to overcome the obstacle, or a certain point on a track assembly may be crushed. Therefore, finding a method to optimize the distance between the track assembly and the wall is essential. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art, such as poor robot stability due to the need for rotatable tracks and high strength requirements for the angle adjustment structure, and to provide a track angle adjustment mechanism and method for a dual-track wall-climbing robot.

[0008] The objective of this invention can be achieved through the following technical solutions:

[0009] This solution provides a track angle adjustment mechanism for a dual-tracked wall-climbing robot, including a fixed frame, a drive assembly, a rotating connection assembly, and a track assembly. The drive assembly is fixed on the fixed frame, and the rotating connection assembly is rotatably fixed on the fixed frame. The drive assembly drives the rotating connection assembly to rotate. The track assembly is connected to the rotating connection assembly. The rotation center axis of the rotating connection assembly is parallel to the movement direction of the track assembly. The rotating connection assembly drives the track assembly to rotate. The track assembly includes a track and an adsorption assembly. The adsorption assemblies are symmetrically arranged on both sides of the track, and the lower plane of the adsorption assembly is parallel to the lower plane of the track.

[0010] Furthermore, the fixing frame has through holes on both sides, and the rotating connection assembly is located in the through holes, and the rotating connection assembly can be rotatably fixed in the through holes.

[0011] Furthermore, the rotating connection assembly is provided with a fixing hole, the central axis of the fixing hole is perpendicular to the rotation center axis of the rotating connection assembly, and the track assembly is fixed in the fixing hole.

[0012] Furthermore, the track assembly also includes a track shaft, one end of which is fixed in a fixing hole and the other end is rotatably connected to the track. The track shaft is used to drive the track to rotate and to adjust the pitch angle of the adsorption assembly.

[0013] Furthermore, the rotating connection assembly and the track shaft are provided with threaded holes at corresponding positions, and there are multiple threaded holes. The rotating connection assembly and the track shaft are connected by bolts.

[0014] Furthermore, the track shaft is a hollow shaft.

[0015] Furthermore, the drive assembly includes a drive motor, a screw, a nut, and a transmission structure. The drive motor is vertically fixed on the mounting frame and drives the connecting screw. The nut is rotatably connected to the screw. One end of the transmission structure is connected to the nut, and the other end is connected to the rotating connecting assembly.

[0016] Furthermore, the transmission structure includes a first link, a second link, and a third link connected in sequence. One end of the first link is fixed to a nut, and the other end is rotatably connected to the second link. One end of the third link is rotatably connected to the second link, and the other end is fixed to a rotating connection assembly.

[0017] This solution also provides a method for adjusting the track angle of a dual-track wall-climbing robot, including the following steps:

[0018] Obtain the center points of the robot's rotation center joint, track tilt joint, track pitch joint, and track lower plane, abstract the robot into a four-degree-of-freedom robotic arm, and establish a robotic arm model;

[0019] The height and rotation angle of the rotation center joint, the tilt angle of the track tilt joint, the pitch angle and pipe radius of the track pitch joint, the distance between the rotation center joint and the track tilt joint, the distance between the track tilt joint and the track pitch joint, and the vertical distance between the track pitch joint and the lower plane of the track are obtained. Based on the obtained angle and length information, the robot arm DH table is obtained.

[0020] A spatial coordinate system is established with the X-axis of the pipe center axis and the Z-axis of the rotation center joint as the Z-axis. The transformation matrix of each joint is obtained, and the coordinate equations of the track pitch joint, the center point of the track lower plane, and the point of tangency between the track lower plane and the pipe cylindrical surface are obtained in the spatial coordinate system.

[0021] The coordinate equations obtained by combining the equations are used to obtain the relationship between the tilt angle of the track tilt joint, the rotation angle of the rotation center joint, and the pipe radius through numerical calculation or numerical fitting under constraints. Based on the obtained relationship, the drive motor is controlled to rotate and the track tilt angle is adjusted.

[0022] Furthermore, the coordinates of the point where the lower plane of the track is tangent to the cylindrical surface of the pipe in the spatial coordinate system are:

[0023] 0 E=T1×T2×T3× c E

[0024] In the formula: 0 E represents the coordinates of the tangent point in the spatial coordinate system, T1 is the transformation matrix of the rotation center joint, T2 is the transformation matrix of the track roll joint, and T3 is the transformation matrix of the track pitch joint. c E represents the coordinates of the tangent point in the track pitch joint coordinate system.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] (1) This solution uses a drive component to rotate a rotating connection component. The rotation direction of the rotating connection component is perpendicular to the rotation direction of the track component, thereby causing the entire track component to rotate. This adjusts the angle of the working surface of the track component to match the diameter of the cylindrical pipe, enabling the robot to climb the pipe. The adaptive adjustment of the track component angle gives the robot good mobility and allows it to perform complex actions such as turning in place, making it more widely applicable. Furthermore, by using the rotating connection component to rotate the track component and adjust the track angle, compared to a direct rotatable connection between the track and the fixed frame, the overall structure is more stable and the angle adjustment of the track component is more consistent.

[0027] (2) In this scheme, the drive motor drives the screw to rotate, which in turn drives the nut to move vertically and linearly, which in turn drives the transmission mechanism to move upward and pulls the rotating connection component to rotate, thereby realizing the adjustment of the track angle; the rotational motion of the motor is converted into the linear motion of the nut through the lead screw, which has low frictional resistance, high sensitivity and no start-up vibration, and high ball screw transmission efficiency and high synchronization.

[0028] (3) In this scheme, the robot is abstracted into a four-degree-of-freedom manipulator, a manipulator model is established, the manipulator DH table is obtained, and the inverse kinematics of the manipulator is calculated. The control law of the tilt angle of the robot track tilt joint is obtained, ensuring that the minimum distance between the adsorption component and the pipeline is always optimal, thereby improving the safety and stability of the robot angle adjustment. Attached Figure Description

[0029] Figure 1 A schematic diagram of the track angle adjustment mechanism of the dual-track wall-climbing robot provided by the present invention;

[0030] Figure 2 This is a top view of the track angle adjustment mechanism of the dual-track wall-climbing robot provided by the present invention;

[0031] Figure 3 This is a cross-sectional view of the internal structure of the wall-climbing robot provided by the present invention;

[0032] Figure 4 This is a partial structural diagram of the bottom of the wall-climbing robot provided by the present invention;

[0033] Figure 5 A schematic diagram of a robot model abstracted as a robotic arm for the present invention;

[0034] Figure 6 A schematic diagram of the transformation matrices for each joint provided by the present invention;

[0035] Figure 7 A diagram showing the relationship between the track tilt angle, the robot rotation angle, and the pipe radius provided by this invention;

[0036] Figure 8 A flowchart of the track angle adjustment method for the dual-track wall-climbing robot provided by the present invention;

[0037] In the diagram: 1. Fixed frame, 2. Drive assembly, 3. Rotary connection assembly, 4. Track assembly, 11. Through hole, 21. Drive motor, 22. Screw, 23. Nut, 24. Transmission structure, 25. First connecting rod, 26. Second connecting rod, 27. Third connecting rod, 31. Fixing hole, 41. Track, 42. Track shaft, 43. Adsorption assembly. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0040] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0041] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed during use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element 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 invention.

[0042] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0043] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0044] Example 1

[0045] like Figure 1 and Figure 3 As shown, this embodiment provides a track angle adjustment mechanism for a dual-track wall-climbing robot, including a fixed frame 1, a drive assembly 2, a rotating connection assembly 3, and a track assembly 4. The drive assembly 2 is fixed on the fixed frame 1, and the rotating connection assembly 3 is rotatably fixed on the fixed frame 1. The drive assembly 2 is used to drive the rotating connection assembly 3 to rotate. The track assembly 4 is connected to the rotating connection assembly 3. The rotation center axis of the rotating connection assembly 3 is parallel to the movement direction of the track assembly 4. The rotating connection assembly 3 is used to drive the track assembly 4 to rotate. The track assembly 4 includes a track 41 and an adsorption assembly 43. The adsorption assembly 43 is symmetrically arranged on both sides of the track 41, and the lower plane of the adsorption assembly 43 is parallel to the lower plane of the track 41.

[0046] Working principle: The drive component 2 drives the rotating connection component 3 to rotate. The rotation direction of the rotating connection component 3 is perpendicular to the rotation direction of the track component 4, thereby driving the track component 4 to rotate as a whole. The angle of the working surface of the track component 4 is adjusted to match the diameter of the cylindrical pipe. The adsorption component ensures a reliable connection with the pipe, thus enabling the track component to climb the cylindrical pipe.

[0047] This solution uses drive component 2 to rotate rotating connection component 3. The rotation direction of rotating connection component 3 is perpendicular to the rotation direction of track component 4, thereby causing the entire track component 4 to rotate. This adjusts the angle of the working surface of track component 4 to match the diameter of the cylindrical pipe. A suction component ensures a reliable connection with the pipe, enabling the robot to climb the cylindrical pipe. The adaptive adjustment of the track component 4's angle gives the robot excellent mobility, allowing it to perform complex actions such as turning in place, thus broadening its applicability. Furthermore, compared to a direct rotatable connection between the track and the fixed frame, using rotating connection component 3 to rotate track component 4 and adjust the track angle provides greater overall structural stability and more consistent angle adjustment for track component 4.

[0048] In a preferred embodiment, the fixing frame 1 has through holes 11 on both sides, and the rotating connecting assembly 3 is located in the through holes 11, and the rotating connecting assembly 3 is rotatably fixed in the through holes 11. Optionally, a bearing is provided between the rotating connecting assembly 3 and the through hole, and the rotating connecting assembly 3 is rotatably connected to the front and rear sides of the bearing through hole 11.

[0049] Furthermore, the rotating connection assembly 3 is provided with a fixing hole 31, the central axis of the fixing hole 31 is perpendicular to the rotation central axis of the rotating connection assembly 3, and the track assembly 4 is fixed in the fixing hole 31.

[0050] By fixing the track assembly 4 to one side of the rotating connection assembly 3, and rotatably fixing the rotating connection assembly 3 in the through hole provided on the fixing frame 1 via the bearing, the rotating connection assembly 3 rotates in the through hole 11 via the bearing, so that the angle adjustment of the track assembly 4 is determined by a single structure, the angle adjustment is more accurate, and the stability of track movement is improved.

[0051] like Figure 3 As shown, the rotating connecting assemblies 3 on both sides of the fixed frame 1 are symmetrically arranged, and the central axes of the through holes 11 on both sides of the fixed frame 1 are parallel to each other. By using the symmetrical rotating connecting assemblies 3, two track assemblies 4 can be symmetrically arranged, so that the robot is subjected to force balance and the robot is prevented from overturning on the wall due to unbalanced forces.

[0052] Specifically, such as Figure 2 As shown, the track assembly 4 also includes a track shaft 42. One end of the track shaft 42 is fixed in the fixing hole 31, and the other end is rotatably connected to the track. The track shaft 42 is used to drive the track 42 to rotate and to adjust the pitch angle of the adsorption assembly 43. Threaded holes are provided at corresponding positions of the rotating connection assembly 3 and the track shaft 42. Multiple threaded holes are provided, and the rotating connection assembly 3 and the track shaft 42 are connected by bolts. In this embodiment, the track shaft 42 can be a hollow shaft, which reduces the weight of the track assembly 4, makes angle adjustment easier, and reduces the burden on the drive assembly 2. Furthermore, compared to the prior art, the track in this application has an additional degree of freedom, resulting in stronger turning adaptability for the wall-climbing robot.

[0053] As a preferred implementation method, such as Figure 3As shown, the drive assembly 2 includes a drive motor 21, a screw 22, a nut 23, and a transmission structure 24. The drive motor 21 is vertically fixed on the mounting bracket 1 and drives the connecting screw 22. The nut 23 is rotatably connected to the screw 22. One end of the transmission structure 24 is connected to the nut 23, and the other end is connected to the rotating connection assembly 3. The transmission structure 24 includes a first connecting rod 25, a second connecting rod 26, and a third connecting rod 27 connected in sequence. One end of the first connecting rod 25 is fixed to the nut 23, and the other end is rotatably connected to the second connecting rod 26. One end of the third connecting rod 27 is rotatably connected to the second connecting rod 26, and the other end is fixed to the rotating connection assembly 3.

[0054] The drive motor drives the screw to rotate, which in turn drives the nut to move vertically in a linear motion. This, in turn, drives the transmission mechanism to move upward, pulling the rotating connection assembly to rotate, thereby adjusting the track angle. The ball screw converts the rotational motion of the motor into the linear motion of the nut, resulting in low frictional resistance, high sensitivity, and no start-up jitter. The ball screw transmission has high efficiency and high synchronization.

[0055] Furthermore, this application employs a T-shaped lead screw and connecting rod structure to control the rotating connection component 3, thereby changing the angle of the track components 4 on both sides. This structure is mechanically self-locking and has strong engineering applicability. Moreover, the drive motor 21 in this application is an integrated drive and control motor, making the overall structure of the wall-climbing robot compact, easy to manufacture, highly precise, with a large load capacity, strong applicability, and good stability.

[0056] In this embodiment, the second link 26 is rotatably connected to the first link 25 and the third link 27 via hinge shafts. The connection structure is simple, easy to connect, and has a strong load-bearing capacity at the connection position.

[0057] The nut 23 has a threaded hole, through which it connects to the first connecting rod 25 of the connecting rod structure 24. Furthermore, the drive assembly 2 has a pair of connecting rod structures 24 symmetrically arranged on both sides of the screw. By symmetrically arranging the connecting rod structures 24, the tilt angles of the two track assemblies 4 can be adjusted simultaneously and at the same angle to adapt to changes in working conditions.

[0058] like Figure 8 As shown, this embodiment also provides an angle adjustment method for the track angle adjustment mechanism of a dual-track wall-climbing robot, including the following steps:

[0059] S1: Obtain the center points of the robot's rotation center joint, track tilt joint, track pitch joint, and track lower plane, abstract the robot into a four-degree-of-freedom robotic arm, and establish a robotic arm model;

[0060] S2: Obtain the height and rotation angle of the rotation center joint, the tilt angle of the track tilt joint, the pitch angle and pipe radius of the track pitch joint, as well as the distance between the rotation center joint and the track tilt joint, the distance between the track tilt joint and the track pitch joint, and the vertical distance between the track pitch joint and the lower plane of the track. Based on the obtained angle and length information, obtain the robot arm DH table.

[0061] S3: Establish a spatial coordinate system with the X-axis of the pipe center axis and the Z-axis of the rotation center joint as the Z-axis, obtain the transformation matrix of each joint, and obtain the coordinate equations of the track pitch joint, the center point of the track lower plane, and the tangent point between the track lower plane and the pipe cylindrical surface in the spatial coordinate system.

[0062] S4: The coordinate equations obtained by combining the equations are used, under constraints, to obtain the relationship between the roll angle of the track roll joint, the rotation angle of the rotation center joint, and the pipe radius through numerical calculation or numerical fitting.

[0063] S5: Based on the obtained relationship, control the rotation of the drive motor and adjust the track tilt angle.

[0064] The coordinates of the point where the lower plane of the track is tangent to the cylindrical surface of the pipe in the spatial coordinate system are:

[0065] 0 E=T1×T2×T3× c E

[0066] In the formula: 0 E represents the coordinates of the tangent point in the spatial coordinate system, T1 is the transformation matrix of the rotation center joint, T2 is the transformation matrix of the track roll joint, and T3 is the transformation matrix of the track pitch joint. c E represents the coordinates of the tangent point in the track pitch joint coordinate system.

[0067] In conjunction with the above-described track angle adjustment mechanism and method, this embodiment also provides an optional implementation method, including the following steps:

[0068] Since the wall-climbing robot and the on-site cylindrical pipe in this invention have symmetrical structures, kinematic analysis of the robot only requires considering the angle between its direction of motion and the cylinder axis. Therefore, by studying only the strategy of adjusting the minimum distance between the adsorption component and the pipe wall when the robot turns in place, a general method can be derived to ensure that the minimum distance between the adsorption component and the pipe wall is optimal at all motion conditions.

[0069] For ease of description, such as Figure 4As shown, the lower plane of the adsorption component and the lower plane of the track are first defined. The geometric relationship between the lower plane of the adsorption component and the cylindrical surface of the pipe determines the minimum distance between the adsorption component and the pipe wall on that side. Through simple geometric proof, it can be seen that during the robot's rotation in place, the optimal minimum distance between the track component and the pipe wall can be guaranteed by keeping the lower plane of the track 41, which is parallel to the lower plane of the adsorption component 43, tangent to the cylindrical surface of the pipe.

[0070] When performing kinematic analysis on the robot's in-situ turning, the robot can be abstracted as a four-degree-of-freedom robotic arm. By establishing a robotic arm model, obtaining the robotic arm DH table, and solving the inverse kinematics of the robotic arm, the control law can be obtained.

[0071] like Figure 5 As shown, point A is the rotation center joint for the robot's in-situ rotation, point B is the track tilt joint, point C is the track pitch joint, D represents the lower plane of the track, and E is the point of tangency between the lower plane of the track and the cylindrical surface of the pipe.

[0072] Joint A can rotate and slide around a vertical axis, representing two degrees of freedom: rotation in place and change of vehicle height; joint B can rotate around one axis, representing the change of the track assembly's side tilt angle; joint C can rotate around one axis, representing the change of the track assembly's pitch angle.

[0073] The height of joint A is represented by h, and the rotation angle is represented by a; the rotation angle of joint B is represented by b; the rotation angle of joint C is represented by c; the length of AB is denoted as l1; the length of BC is denoted as l2; the radius of the pipe is denoted as R; the vertical distance between point C and the lower plane of the track is l3. From this, the DH table of the robotic arm can be obtained.

[0074] Establish a spatial coordinate system with the central axis of the cylindrical pipe as the x-axis and the rotation center axis of joint A as the z-axis. Then, the transformation matrices for each joint are as follows: Figure 6 As shown.

[0075] Where T1, T2, and T3 correspond to the transformation matrices of joints A, B, and C, respectively. Let the coordinates of point E in the coordinate system of joint C be... c E, then the coordinates of point E in the spatial coordinate system are

[0076] 0 E=T1×T2×T3× c E

[0077] Similarly, the coordinates of points C and D in the spatial coordinate system can be obtained.

[0078] Under the constraints that the lower plane of the track is perpendicular to the cylindrical surface of the pipe and the tangency point is E, by solving the simultaneous equations and using numerical calculations, the relationship between the side tilt angle b, the in-situ rotation angle a, and the pipe radius R can be determined, as follows: Figure 7As shown. A fitting equation for the track component tilt angle b of this type of robot with respect to the in-situ rotation angle a and the pipe radius R can also be obtained through numerical fitting, and the rotation of the drive motor can be controlled based on this equation.

[0079] The drive motor rotates the screw, which in turn moves the nut up and down. The linear motion of the nut is converted into the oscillation of the track assembly through a transmission structure. This ensures that the distance between the track assembly and the pipe wall is kept optimal in real time. The pitch angle of the track assembly is a passive joint, achieved by the track shaft on the track assembly, and does not require adjustment during vehicle rotation.

[0080] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A track angle adjustment mechanism for a dual-tracked wall-climbing robot, characterized in that, The system includes a fixed frame (1), a drive assembly (2), a rotating connection assembly (3), and a track assembly (4). The drive assembly (2) is fixed on the fixed frame (1), and the rotating connection assembly (3) is rotatably fixed on the fixed frame (1). The drive assembly (2) is used to drive the rotating connection assembly (3) to rotate. The track assembly (4) is connected to the rotating connection assembly (3). The rotation center axis of the rotating connection assembly (3) is parallel to the movement direction of the track assembly (4). The rotating connection assembly (3) is used to drive the track assembly (4) to rotate. The track assembly (4) includes a track (41) and an adsorption assembly (43). The adsorption assembly (43) is symmetrically arranged on both sides of the track (41), and the lower plane of the adsorption assembly (43) is parallel to the lower plane of the track (41). The angle adjustment method of the track angle adjustment mechanism includes the following steps: Obtain the center points of the robot's rotation center joint, track tilt joint, track pitch joint, and track lower plane, abstract the robot into a four-degree-of-freedom robotic arm, and establish a robotic arm model; The height and rotation angle of the rotation center joint, the tilt angle of the track tilt joint, the pitch angle and pipe radius of the track pitch joint, the distance between the rotation center joint and the track tilt joint, the distance between the track tilt joint and the track pitch joint, and the vertical distance between the track pitch joint and the lower plane of the track are obtained. Based on the obtained angle and length information, the robot arm DH table is obtained. A spatial coordinate system is established with the X-axis of the pipe center axis and the Z-axis of the rotation center joint as the Z-axis. The transformation matrix of each joint is obtained, and the coordinate equations of the track pitch joint, the center point of the track lower plane, and the point of tangency between the track lower plane and the pipe cylindrical surface are obtained in the spatial coordinate system. The coordinate equations obtained by combining the equations are used to obtain the relationship between the tilt angle of the track tilt joint, the rotation angle of the rotation center joint, and the pipe radius through numerical calculation or numerical fitting under the constraints. Based on the obtained relationship, the drive motor is controlled to rotate and the track tilt angle is adjusted. The coordinates of the point where the lower plane of the track is tangent to the cylindrical surface of the pipe in the spatial coordinate system are: In the formula: Let T1 be the coordinates of the tangent point in the spatial coordinate system, T2 be the transformation matrix of the rotation center joint, T3 be the transformation matrix of the track roll joint, and T4 be the transformation matrix of the track pitch joint. The coordinates of the tangent point in the track pitch joint coordinate system.

2. The track angle adjustment mechanism for a dual-tracked wall-climbing robot according to claim 1, characterized in that, The fixing frame (1) has through holes (11) on both sides, and the rotating connection component (3) is located in the through hole (11). The rotating connection component (3) can be rotatably fixed in the through hole (11).

3. The track angle adjustment mechanism for a dual-tracked wall-climbing robot according to claim 2, characterized in that, The rotating connection assembly (3) is provided with a fixing hole (31), the central axis of the fixing hole (31) is perpendicular to the rotation center axis of the rotating connection assembly (3), and the track assembly (4) is fixed in the fixing hole (31).

4. The track angle adjustment mechanism for a dual-tracked wall-climbing robot according to claim 3, characterized in that, The track assembly (4) also includes a track shaft (42), one end of which is fixed in a fixing hole (31) and the other end is rotatably connected to the track. The track shaft (42) is used to drive the track (42) to rotate and to adjust the pitch angle of the adsorption assembly (43).

5. The track angle adjustment mechanism for a dual-tracked wall-climbing robot according to claim 4, characterized in that, The rotating connection assembly (3) and the track shaft (42) are provided with threaded holes at corresponding positions. There are multiple threaded holes. The rotating connection assembly (3) and the track shaft (42) are connected by bolts.

6. The track angle adjustment mechanism for a dual-tracked wall-climbing robot according to claim 4, characterized in that, The track shaft (42) is a hollow shaft.

7. The track angle adjustment mechanism for a dual-tracked wall-climbing robot according to claim 1, characterized in that, The drive assembly (2) includes a drive motor (21), a screw (22), a nut (23) and a transmission structure (24). The drive motor (21) is vertically fixed on the fixed frame (1). The drive motor (21) drives the connecting screw (22). The nut (23) is rotatably connected to the screw (22). One end of the transmission structure (24) is connected to the nut (23), and the other end is connected to the rotating connection assembly (3).

8. The track angle adjustment mechanism for a dual-tracked wall-climbing robot according to claim 7, characterized in that, The transmission structure (24) includes a first link (25), a second link (26) and a third link (27) connected in sequence. One end of the first link (25) is fixed to a nut (23) and the other end is rotatably connected to the second link (26). One end of the third link (27) is rotatably connected to the second link (26) and the other end is fixed to the rotating connection assembly (3).

Images