Crawling gait planning method for crawling mechanical arm

Abstract

The invention relates to a crawling gait planning method for a crawling mechanical arm, and belongs to the technical field of mechanical arm motion control and motion planning. Comprising the following steps: configuring a mechanical arm; a starting point, a target point and a movement track of the mechanical arm are given, and grids are divided; calculating an included angle and a distance according to the relative displacement of the first middle point and the starting point; the motion angle of the pitching joint is solved according to inverse kinematics, the mechanical arm moves to the position above a preset connector of a first middle point, then the mechanical arm vertically descends to make contact with the preset connector, the second tail end of the designated mechanical arm grabs the preset connector, and the first tail end of the designated mechanical arm is loosened; the movement angle of the pitching joint is solved again, so that the movement distance of the mechanical arm is achieved, and a working space is reserved for subsequent movement; according to the relative displacement between the second middle point and the first middle point, the vector, the included angle and the distance of the second middle point and the first middle point under the tail end two-coordinate system and the motion mode judgment angle of the mechanical arm are worked out; and judging whether the angle is larger than the reachable angle range of the seventh joint of the mechanical arm.

Description

Technical Field

[0001] This invention relates to a crawling gait planning method for a robotic arm, belonging to the field of robotic arm motion control and motion planning technology. Background Technology

[0002] For multi-degree-of-freedom robotic arms, planning the high-speed, orderly motion of each joint is a prerequisite for the robotic arm to complete its work objectives quickly and efficiently. Most existing robotic arm motion planning methods consider the case where one end is fixed and the other end is free, without considering the case where the two ends can alternately crawl.

[0003] Furthermore, existing crawling robotic arms, such as the one published in CN115302504B entitled "A Distributed Control System for a Mobile Robotic Arm Supporting Shoulder-Wrist Interchange," only emphasize the ability to move and crawl through shoulder-wrist interchange. They do not define specific motion modes, joint coordination, or movement sequences, meaning a standardized gait has not yet been established, resulting in low motion efficiency and complex planning methods. The classic inchworm gait has a short stride, making it difficult to adapt to large-scale, rapid movements. For multi-degree-of-freedom robotic arms, researching the gait of alternating crawling at both ends remains a technical challenge.

[0004] Therefore, there is an urgent need to propose a crawling gait planning method for crawling robotic arms to solve the above-mentioned technical problems. Summary of the Invention

[0005] To address the aforementioned problems, a crawling gait planning method for a crawling robotic arm is provided. A brief overview of the invention is given below to provide a basic understanding of certain aspects of the invention. It should be understood that this overview is not an exhaustive summary of the invention. It is not intended to identify key or essential parts of the invention, nor is it intended to limit the scope of the invention.

[0006] The technical solution of the present invention:

[0007] A crawling gait planning method for a crawlable robotic arm includes the following steps: Step 1: Configure the robotic arm; Step 2: Given the starting point, target point, and motion trajectory of the robotic arm, divide the grid according to the number of path points n passed through in the path; Step 3: Based on the relative displacement between the first intermediate point and the starting point, express it as a vector. And calculate the included angle. ,distance ; Step 4: Solve for the pitch joint's motion angle using inverse kinematics to determine the robotic arm's movement distance. The robot arm descends vertically above the preset interface at the first midpoint until it contacts the preset interface, then the end effector grips the preset interface and releases it. The inverse kinematics is then used to calculate the pitch joint's motion angle to determine the robot arm's movement distance. This makes room for subsequent activities; Step 5: Based on the relative displacement between the second intermediate point and the first intermediate point, calculate the vectors of the second intermediate point and the first intermediate point in the final coordinate system. Angle ,distance And the angle of the robotic arm's movement. ; Step Six: Determine if the angle exceeds the reachable range of the seventh joint of the robotic arm. .

[0008] Preferred: In step one, the robotic arm is a symmetrical seven-degree-of-freedom robotic arm. All joints of the robotic arm are rotary joints, with a total of seven joints. Each joint has a degree of freedom of rolling or pitching. Rolling and pitching are alternately configured. The center points of the seven joints are on the same straight line when they are in the zero position. End tools are installed at both ends of the crawling robotic arm.

[0009] Preferred method: In step two, given the endpoint of the robotic arm's movement, a coordinate system is established with the robotic arm's starting point as the origin. In this coordinate system, the endpoint is represented as a vector. The path grid is formed by dividing the X and Y axes between the start and end points at equal intervals: (1) in, These are the X and Y components of the endpoint relative to the target point's coordinate system, respectively. This represents the number of segments on the X and Y axes between the start and end points. These represent the length and width spacing of the resulting grid; The robotic arm's path points fall at the intersections of the grid. The robotic arm from The process begins with steps three through seven iterations, until the endpoint is reached.

[0010] Preferably, in step three, a gripping starting point is specified at the end of the robotic arm, and a coordinate system is established with the end of the robotic arm as the center at the gripping point. When the robotic arm moves to the first intermediate point, the relative displacement between the intermediate point and the starting point is first represented as a vector in the coordinate system established relative to the end point. Therefore, the angle between the first moving point and the starting point can be calculated. and distance :

[0011]

[0012] (2) in, Let be the vector representing the relative position of the first intermediate point and the starting point within the coordinate system of the last point. Let X be the component of the vector in the X direction in the coordinate system. Let Y be the component of the vector in the Y direction in the coordinate system. Let be the angle between the first intermediate point and the starting point relative to the end point in the X-axis of a coordinate system. This is the distance between the first intermediate point and the starting point relative to the end point in a coordinate system.

[0013] Preferably, in step four, moving the robotic arm to the first path point includes the following steps: Step 41: Calculate the included angle in Step 3. Assign it to the first joint of the robotic arm to allow it to rotate. This causes the end effector of the robotic arm to point in the X direction of the coordinate system towards the first midpoint. Step 42: Using the inverse kinematics of the robotic arm, solve for the motion angles of the second, fourth, and sixth joints:

[0014]

[0015] (3) in, Let be the angle between the first intermediate point and the starting point relative to the end point in the X-axis of a coordinate system. The distance between the first intermediate point and the starting point relative to the end point in one coordinate system; The overall length of the robotic arm is a known quantity given the robotic arm itself; it is derived from the inverse kinematics function. , and The motion angles of the second, fourth, and sixth joints can be calculated sequentially. ; Step 43: Rotate the angles using the second, fourth, and sixth joints respectively. To make the robotic arm move The distance is such that the robot arm moves to the top of the preset interface at the first midpoint, then descends vertically to contact the preset interface, the end effector of the robot arm grips the preset interface, and the end effector of the robot arm releases the interface. Step 44: Again, solve the pitch joint motion angle using the inverse kinematics of the robotic arm, thereby raising the end effector of the robotic arm. To make room for subsequent activities:

[0016]

[0017] (4) in, Given the preset interface height during the movement, solve for the method to raise the robotic arm. pitch joint angle values .

[0018] Preferably, in step five, when the robotic arm moves to the second intermediate point, a coordinate system is established at the two gripping points at the end of the robotic arm. Based on the relative displacement between the second intermediate point and the first intermediate point, this displacement is represented as a vector relative to the coordinate system established at the two end points. and according to Calculate the angle between the second midpoint and the first midpoint. and distance And the angle determined by the movement mode of the robotic arm. :

[0019]

[0020]

[0021] (5) in, Let be the vector representing the relative position of the second intermediate point to the first intermediate point within the coordinate system of the last two points. Let X be the component of the vector in the X direction in the coordinate system. Let Y be the component of the vector in the Y direction in the coordinate system. Let be the angle between the second midpoint and the first midpoint relative to the end point in the coordinate system along the X direction. Let be the distance between the second intermediate point and the first intermediate point relative to the endpoints in the two coordinate systems. This is the reference angle used in this method to determine how the robotic arm moves to the next intermediate point.

[0022] Preferred method: In step six, the judgment angle is selected based on the robotic arm motion mode calculated in step four. and the range of motion of the seventh joint of the robotic arm. The determination of whether the robotic arm can reach the second intermediate point through a large-angle rotation of the seventh joint includes: Determine the angle Greater than That is, the required rotation angle exceeds the reach of the seventh joint of the robotic arm. Based on this, when the robotic arm moves to the second intermediate point, it adopts the whole arm flipping method to move. Return the seven joints of the robotic arm to their zero position, i.e., align them on a straight line, and then rotate the seventh joint of the robotic arm. The degree is adjusted so that the two coordinate systems at the end of the robotic arm are oriented toward the second midpoint. Then, step four is repeated to complete the movement at that point. Determine the angle Less than That is, the required rotation angle is within the reach of the seventh joint of the robotic arm. Therefore, when the robotic arm moves to the second intermediate point, it adopts the robotic arm rolling movement mode. Judging angle Assign the value to the seventh joint of the robotic arm to make it rotate. Then, by using inverse kinematics to solve for the pitch joint angle of the robotic arm, the movement angle of the robotic arm can be determined. distance;

[0023]

[0024] (6) in, All of these are known quantities calculated in the above steps; therefore, the motion angles of the second, fourth, and sixth joints are solved separately. .

[0025] Preferred option: also includes step seven: The subsequent process of the robotic arm reaching all intermediate points follows steps five and six. First, the judgment angle for each step is calculated. And based on the judgment angle of each step. The gait planning method for the robotic arm is completed by selecting the movement mode for the robotic arm to reach the next intermediate point until the robotic arm reaches the endpoint.

[0026] The present invention has the following beneficial effects: The method described in this invention autonomously plans the movement mode used at each step of the path according to the movement distance and angle of each step of the robotic arm and the selection algorithm. It is highly adaptable to different scenarios, can quickly and efficiently complete gait planning, and reach the target point quickly, thereby improving work efficiency. The method described in this invention is based on a pre-set robotic arm motion pattern and judgment algorithm, which can flexibly adjust the planned gait according to actual conditions and is easy to implement in engineering. Attached Figure Description

[0027] Figure 1 This is a flowchart of a crawling gait planning method for a crawling robotic arm.

[0028] Figure 2 A schematic diagram illustrating the degrees of freedom of the robotic arm.

[0029] Figure 3 This is to build a simulation platform for the crawling gait planning of a robotic arm.

[0030] Figure 4 The simulation gait node diagram for robotic arm crawling gait planning includes: (a) Initial posture of the robotic arm; (b) Move to the first midpoint; (c) The robotic arm is used for full-arm flipping motion; (d) Move to the second midpoint; (e) The movement is achieved by using a robotic arm to roll laterally; (f) Move to the third intermediate point; (g) The robotic arm moves to the target point.

[0031] Figure 5 The simulation curve of the first joint angle change for the crawling gait planning of the robotic arm.

[0032] Figure 6 The simulation curve of the second joint angle change for the crawling gait planning of the robotic arm.

[0033] Figure 7 The simulation curve of the third joint angle change for the crawling gait planning of the robotic arm.

[0034] Figure 8 The simulation curve of the fourth joint angle change for the crawling gait planning of the robotic arm.

[0035] Figure 9 The simulation curve of the fifth joint angle change for the crawling gait planning of the robotic arm.

[0036] Figure 10 The simulation curve of the sixth joint angle change for the robotic arm crawling gait planning.

[0037] Figure 11 The simulation curve of the seventh joint angle change for the crawling gait planning of the robotic arm. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0039] Specific implementation method one: Combining Figure 1-11 This embodiment describes a crawling gait planning method for a crawlable robotic arm, comprising the following steps: Step 1: Configure the robotic arm; Step 2: Given the starting point, target point, and motion trajectory of the robotic arm, divide the grid according to the number of path points n passed through in the path; Step 3: Based on the relative displacement between the first intermediate point and the starting point, express it as a vector. And calculate the included angle. ,distance ; Step 4: Solve for the motion angles of the second, fourth, and sixth joints (i.e., the pitch joints) using inverse kinematics. This allows the robotic arm to travel a certain distance. The robot arm descends vertically above the preset interface at the first midpoint until it contacts the preset interface, then the end effector grips the preset interface and releases it. The inverse kinematics is then used to calculate the pitch joint's motion angle to determine the robot arm's movement distance. This makes room for subsequent activities; Step 5: Based on the relative displacement between the second intermediate point and the first intermediate point, calculate the vectors of the second intermediate point and the first intermediate point in the final coordinate system. Angle ,distance And the angle of the robotic arm's movement. ; Step Six: Determine if the angle exceeds the reachable range of the seventh joint of the robotic arm. ; Based on a symmetrical seven-degree-of-freedom robotic arm, the starting point and target point of the robotic arm's movement are given under different task objectives. The intermediate points to be passed are divided. Through the corresponding algorithm, the distance and angle between the robotic arm and the next movement point are judged in real time. According to the workspace that the robotic arm can reach, it can flexibly choose to move to the next movement point by rolling or pitching. By repeatedly applying this algorithm, the robotic arm can flexibly choose the gait to move forward in sequence and finally reach the target point.

[0040] Specific Implementation Method Two: Combining Figure 1-11 This embodiment describes a crawling gait planning method for a crawling robotic arm. In step one, the robotic arm is a symmetrical seven-degree-of-freedom robotic arm. All joints of the robotic arm are rotary joints, with a total of seven joints. Each joint has either a rolling or pitch degree of freedom, and the rolling and pitch degrees are alternately arranged. The center points of the seven joints are on the same straight line when in the zero position. End tools are installed at both ends of the crawling robotic arm, and the end tools can be gripping tools. Figure 2In the design, the end effector at the left end of the robotic arm, the first joint, the first arm, the second joint, the second arm, the third joint, the third arm, the fourth joint, the fourth arm, the fifth joint, the fifth arm, the sixth joint, the sixth arm, the seventh joint, and the end effector at the right end of the robotic arm are connected in sequence. The joints, end effector mechanisms, and arms are symmetrically arranged on both sides of the fourth joint. The first joint, the third joint, the fifth joint, and the seventh joint can be rolling joints, and the second joint, the fourth joint, and the sixth joint can be pitch joints.

[0041] Specific implementation method three: Combining Figure 1-11 This embodiment describes a crawling gait planning method for a crawlable robotic arm. In step two, given the endpoint of the robotic arm's movement, a coordinate system is established with the starting point of the robotic arm as the origin. In this coordinate system, the endpoint is represented as a vector. The path grid is formed by dividing the X and Y axes between the start and end points at equal intervals: (1) in, These are the X and Y components of the endpoint relative to the target point's coordinate system, respectively. This represents the number of segments on the X and Y axes between the start and end points. These represent the length and width spacing of the resulting grid; The robotic arm's path points fall at the intersections of the grid. The robotic arm from Starting from the starting point, the movement continues through steps three through seven iterations until the endpoint is reached.

[0042] Specific implementation method four: Combination Figure 1-11 This embodiment describes a crawling gait planning method for a crawlable robotic arm. In step three, a gripping starting point is specified at the end effector of the robotic arm, and a coordinate system is established with the end effector as the center at the gripping point. When the robotic arm moves to the first intermediate point, the relative displacement between the intermediate point and the starting point is first represented as a vector in the coordinate system established relative to the end effector (end tool). Therefore, the angle between the first moving point and the starting point can be calculated. and distance :

[0043]

[0044] (2) in, Let be the vector representing the relative position of the first intermediate point and the starting point within the coordinate system of the last point. Let X be the component of the vector in the X direction in the coordinate system. Let Y be the component of the vector in the Y direction in the coordinate system. Let be the angle between the first intermediate point and the starting point relative to the end point in the X-axis of a coordinate system. This is the distance between the first intermediate point and the starting point relative to the end point in a coordinate system.

[0045] Specific Implementation Method Five: Combining Figure 1-11 This embodiment describes a crawling gait planning method for a crawlable robotic arm. Step four, which moves the robotic arm to the first path point, includes the following steps: Step 41: Calculate the included angle in Step 3. Assign it to the first joint of the robotic arm to allow it to rotate. This causes the end effector of the robotic arm to point in the X direction of the coordinate system towards the first midpoint. Step 42: Using the inverse kinematics of the robotic arm, solve for the motion angles of the second, fourth, and sixth joints (i.e., the pitch joints):

[0046]

[0047] (3) in, Let be the angle between the first intermediate point and the starting point relative to the end point in the X-axis of a coordinate system. The distance between the first intermediate point and the starting point relative to the end point in a coordinate system has been calculated in step three. The overall length of the robotic arm is a known quantity when the robotic arm is given a specific value; therefore All have been obtained from the inverse kinematic function , and The motion angles of the second, fourth, and sixth joints can be calculated sequentially. ; Step 43: Rotate the angles using the second, fourth, and sixth joints respectively. To make the robotic arm move The distance is such that the robot arm moves to the top of the preset interface at the first midpoint, then descends vertically to contact the preset interface, the end effector of the robot arm grips the preset interface, and the end effector of the robot arm releases the interface. Step 44: Again, solve the pitch joint motion angle using the inverse kinematics of the robotic arm, thereby raising the end effector of the robotic arm. To make room for subsequent activities:

[0048]

[0049] (4) in, Given the preset interface height during the movement, solve for the method to raise the robotic arm. pitch joint angle values .

[0050] Specific Implementation Method Six: Combination Figure 1-11 This embodiment describes a crawling gait planning method for a crawling robotic arm. In step five, when the robotic arm moves to the second intermediate point, a coordinate system is established at the two gripping points at the end of the robotic arm. Based on the relative displacement between the second intermediate point and the first intermediate point, this displacement is represented as a vector relative to the coordinate system established at the two end points. and according to Calculate the angle between the second midpoint and the first midpoint. and distance And the angle determined by the movement mode of the robotic arm. :

[0051]

[0052]

[0053] (5) in, Let be the vector representing the relative position of the second intermediate point to the first intermediate point within the coordinate system of the last two points. Let X be the component of the vector in the X direction in the coordinate system. Let Y be the component of the vector in the Y direction in the coordinate system. Let be the angle between the second midpoint and the first midpoint relative to the end point in the coordinate system along the X direction. Let be the distance between the second intermediate point and the first intermediate point relative to the endpoints in the two coordinate systems. The reference angle is used in the method of the present invention to determine how the robotic arm moves to the next intermediate point.

[0054] Specific implementation method seven: Combination Figure 1-11 This embodiment describes a crawling gait planning method for a crawlable robotic arm. In step six, a judgment angle is selected based on the robotic arm's motion pattern calculated in step four. and the range of motion of the seventh joint of the robotic arm. The system determines whether the robotic arm can reach the second intermediate point by rotating at a large angle through the seventh joint (i.e., the pitch joint), including determining the angle. Greater than Judging angle Less than or equal to : Determine the angle Greater than That is, the required rotation angle exceeds the reach of the seventh joint of the robotic arm. Based on this, when the robotic arm moves to the second intermediate point, it adopts the whole arm flipping method to move. First, return the seven joints of the robotic arm to their zero position, that is, to be on the same straight line. Then, adjust the angle between the second midpoint and the first midpoint. Assigning to the seventh joint of the robotic arm means specifying the rotation of the seventh joint of the robotic arm. The degree is adjusted so that the two coordinate systems at the end of the robotic arm are oriented toward the second midpoint. Then, step four is repeated to complete the movement at that point. Determine the angle Less than That is, the required rotation angle is within the reach of the seventh joint of the robotic arm. Therefore, when the robotic arm moves to the second intermediate point, it adopts the robotic arm rolling movement mode. Judging angle Assign the value to the seventh joint of the robotic arm to make it rotate. Then, by using inverse kinematics to solve for the pitch joint angle of the robotic arm, the movement angle of the robotic arm can be determined. distance;

[0055]

[0056] (6) in, All of these are known quantities calculated in the above steps; therefore, the motion angles of the second, fourth, and sixth joints are solved separately. ; The method described in this invention autonomously plans the movement mode used at each step of the path according to the movement distance and angle of the robotic arm in each step, based on a selection algorithm. It is highly adaptable to different scenarios, can quickly and efficiently complete gait planning, and rapidly reach the target point, thereby improving work efficiency. The pre-set robotic arm movement mode and judgment algorithm can flexibly adjust the planned gait according to actual conditions, making it easy to implement in engineering.

[0057] Specific implementation method eight: Combination Figure 1-11 This embodiment describes a crawling gait planning method for a crawlable robotic arm, which further includes step seven: The subsequent process of the robotic arm reaching all intermediate points is similar to steps five and six. First, the judgment angle for each step is calculated. And based on the judgment angle of each step. The gait planning method for the robotic arm is completed by selecting the movement mode for the robotic arm to reach the next intermediate point until the robotic arm reaches the endpoint.

[0058] Example 1: To verify the effectiveness of the present invention, the configuration is as follows: Figure 2 The robotic arm shown is constructed as follows: Figure 3 The robotic arm crawling gait planning simulation platform shown in this embodiment, given a robotic arm path, performs gait planning and combines... Figure 1 The technical solution of the present invention is further described, including the following steps: Step 1: Configure the robot arm's degrees of freedom, specifying the starting point, ending point, and intermediate points of the robot arm's movement, as follows: Figure 3 As shown.

[0059] Step 2: Based on the X and Y components of the endpoint relative to the target point's coordinate system, obtain the vector and represent it as a vector. Based on the number of path points traversed The resulting grid spacing is:

[0060] Step 3: Based on the relative displacement between the first intermediate point and the starting point, represent it as a vector. , Therefore, the angle between the first moving point and the starting point can be calculated. and distance .

[0061] Step 4: Calculate the included angle in Step 2. Assign it to joint 1 of the robotic arm to rotate. This causes the end effector of the robotic arm to point in the X direction of the coordinate system towards the first midpoint. Given the distance the robotic arm's end effector needs to move. By using the inverse kinematics of the robotic arm, the motion angles of joints 2, 4, and 6 can be solved. Rotate by angles through joints 2, 4, and 6 respectively. To make the robotic arm move The distance is such that the robot arm moves to the top of the preset interface at the first midpoint, then descends vertically to contact the preset interface, the end effector of the robot arm grips the preset interface, and the end effector of the robot arm releases the interface. The pitch joint motion angle is solved again by inverse kinematics of the robotic arm, thereby enabling the end effector of the robotic arm to lift. To make room for subsequent activities, such as Figure 4 As shown in (b).

[0062] Step 5: Based on the relative displacement between the second intermediate point and the first intermediate point, express this displacement as a vector. and according to Calculate the angle between the second midpoint and the first midpoint. and distance And the angle determined by the movement mode of the robotic arm. .

[0063] Step Six: Determine the angle calculated in Step Four and the range of motion of the robotic arm joint 7 To determine the next movement of the robotic arm: In this example, because The range of motion of the robotic arm joint 7 is , Greater than Therefore, the second step uses a robotic arm rotation method, such as... Figure 4 As shown in (c); Step 7: Repeat steps S4-S5 until the robotic arm moves to the target point, at which point the movement ends.

[0064] This embodiment demonstrates that the robotic arm can autonomously perform gait planning and select the appropriate movement mode through this algorithm.

[0065] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be permuted and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutation and combination. Therefore, the present invention will not describe the technical solutions after permutation and combination one by one, but it should be understood that the technical solutions after permutation and combination have been disclosed by the present invention.

[0066] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A crawling gait planning method for a crawling robotic arm, characterized in that: Includes the following steps: Step 1: Configure the robotic arm; Step 2: Given the starting point, target point, and motion trajectory of the robotic arm, divide the grid according to the number of path points n passed through in the path; Step 3: Based on the relative displacement between the first intermediate point and the starting point, express it as a vector. And calculate the included angle. ,distance ; Step 4: Solve for the pitch joint's motion angle using inverse kinematics to determine the robotic arm's movement distance. The robot arm descends vertically above the preset interface at the first midpoint until it contacts the preset interface, then the end effector grips the preset interface and releases it. The inverse kinematics is then used to calculate the pitch joint's motion angle to determine the robot arm's movement distance. This makes room for subsequent activities; Step 5: Based on the relative displacement between the second intermediate point and the first intermediate point, calculate the vectors of the second intermediate point and the first intermediate point in the final coordinate system. Angle ,distance And the angle of the robotic arm's movement. ; Step Six: Determine if the angle exceeds the reachable range of the seventh joint of the robotic arm. .

2. The crawling gait planning method for a crawlable robotic arm according to claim 1, characterized in that: In step one, the robotic arm is a symmetrical seven-degree-of-freedom robotic arm. All joints of the robotic arm are rotary joints, with a total of seven joints. Each joint has a degree of freedom of rolling or pitching. Rolling and pitching are arranged alternately. The center points of the seven joints are on the same straight line when they are in the zero position. End tools are installed at both ends of the crawling robotic arm.

3. The crawling gait planning method for a crawlable robotic arm according to claim 2, characterized in that: In step two, given the endpoint of the robotic arm's movement, a coordinate system is established with the robotic arm's starting point as the origin. In this coordinate system, the endpoint is represented as a vector. The path grid is formed by dividing the X and Y axes between the start and end points at equal intervals: (1) in, These are the X and Y components of the endpoint relative to the target point's coordinate system, respectively. This represents the number of segments on the X and Y axes between the start and end points. These represent the length and width spacing of the resulting grid; The robotic arm's path points fall at the intersections of the grid. The robotic arm from The process begins with steps three through seven iterations, until the endpoint is reached.

4. The crawling gait planning method for a crawlable robotic arm according to claim 3, characterized in that: In step three, a gripping starting point is specified at the end effector of the robotic arm, and a coordinate system is established with the end effector as the center at the gripping point. When the robotic arm moves to the first intermediate point, the relative displacement between the intermediate point and the starting point is first represented as a vector in the coordinate system established relative to the end effector. Therefore, the angle between the first moving point and the starting point can be calculated. and distance : (2) in, Let be the vector representing the relative position of the first intermediate point and the starting point within the coordinate system of the last point. Let X be the component of the vector in the X direction in the coordinate system. Let Y be the component of the vector in the Y direction in the coordinate system. Let be the angle between the first intermediate point and the starting point relative to the end point in the X-axis of a coordinate system. This is the distance between the first intermediate point and the starting point relative to the end point in a coordinate system.

5. The crawling gait planning method for a crawlable robotic arm according to claim 4, characterized in that: Step four involves moving the robotic arm to the first path point, including the following steps: Step 41: Calculate the included angle in Step 3. Assign it to the first joint of the robotic arm to allow it to rotate. This causes the end effector of the robotic arm to point in the X direction of the coordinate system towards the first midpoint. Step 42: Using the inverse kinematics of the robotic arm, solve for the motion angles of the second, fourth, and sixth joints: (3) in, Let be the angle between the first intermediate point and the starting point relative to the end point in the X-axis of a coordinate system. The distance between the first intermediate point and the starting point relative to the end point in one coordinate system; The overall length of the robotic arm is a known quantity given the robotic arm itself; it is derived from the inverse kinematics function. , and The motion angles of the second, fourth, and sixth joints can be calculated sequentially. ; Step 43: Rotate the angles using the second, fourth, and sixth joints respectively. To make the robotic arm move The distance is such that the robot arm moves to the top of the preset interface at the first midpoint, then descends vertically to contact the preset interface, the end effector of the robot arm grips the preset interface, and the end effector of the robot arm releases the interface. Step 44: Again, solve the pitch joint motion angle using the inverse kinematics of the robotic arm, thereby raising the end effector of the robotic arm. To make room for subsequent activities: (4) in, Given the preset interface height during the movement, solve for the method to raise the robotic arm. pitch joint angle values .

6. The crawling gait planning method for a crawlable robotic arm according to claim 5, characterized in that: In step five, when the robotic arm moves to the second intermediate point, a coordinate system is established at the two gripping points at the end of the robotic arm. Based on the relative displacement between the second intermediate point and the first intermediate point, this displacement is represented as a vector relative to the coordinate system established at the end of the robotic arm. and according to Calculate the angle between the second midpoint and the first midpoint. and distance And the angle determined by the movement mode of the robotic arm. : (5) in, Let be the vector representing the relative position of the second intermediate point to the first intermediate point within the coordinate system of the last two points. Let X be the component of the vector in the X direction in the coordinate system. Let Y be the component of the vector in the Y direction in the coordinate system. Let be the angle between the second midpoint and the first midpoint relative to the end point in the coordinate system along the X direction. Let be the distance between the second intermediate point and the first intermediate point relative to the endpoints in the two coordinate systems. This is the reference angle used in this method to determine how the robotic arm moves to the next intermediate point.

7. The crawling gait planning method for a crawlable robotic arm according to claim 6, characterized in that: In step six, the judgment angle is selected based on the robotic arm motion pattern calculated in step four. and the range of motion of the seventh joint of the robotic arm. The determination of whether the robotic arm can reach the second intermediate point through a large-angle rotation of the seventh joint includes: Determine the angle Greater than That is, the required rotation angle exceeds the reach of the seventh joint of the robotic arm. Based on this, when the robotic arm moves to the second intermediate point, it adopts the whole arm flipping method to move. Return the seven joints of the robotic arm to their zero position, i.e., align them on a straight line, and then rotate the seventh joint of the robotic arm. The degree is adjusted so that the two coordinate systems at the end of the robotic arm are oriented toward the second midpoint. Then, step four is repeated to complete the movement at that point. Determine the angle Less than That is, the required rotation angle is within the reach of the seventh joint of the robotic arm. Therefore, when the robotic arm moves to the second intermediate point, it adopts the robotic arm rolling movement mode. Judging angle Assign the value to the seventh joint of the robotic arm to make it rotate. Then, by using inverse kinematics to solve for the pitch joint angle of the robotic arm, the movement angle of the robotic arm can be determined. distance; (6) in, All of these are known quantities calculated in the above steps; therefore, the motion angles of the second, fourth, and sixth joints are solved separately. .

8. The crawling gait planning method for a crawlable robotic arm according to claim 7, characterized in that: It also includes step seven: The subsequent process of the robotic arm reaching all intermediate points is similar to steps five and six. First, the judgment angle for each step is calculated. And based on the judgment angle of each step. The gait planning method for the robotic arm is completed by selecting the movement mode for the robotic arm to reach the next intermediate point until the robotic arm reaches the endpoint.

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