Mechanical arm track calculation method for uniform cylindrical object matrix point locations

Abstract

The invention relates to the technical field of machining, in particular to a mechanical arm track calculation method for uniform cylindrical object matrix point positions, which comprises the following steps of: importing a workpiece model into a control system, and setting workpiece machining point positions; the position coordinates of the mechanical arm flange are calculated, and the rotation angle of each shaft of the mechanical arm flange is inversely calculated; generating a mechanical arm posture set of all machining point positions, and calculating a total value of axis change absolute values and each group of axis change variances of an original axis; the total absolute value and the axis change variance are sorted and weighted, a final sorting score is obtained, and the machining position postures of the two points are obtained; according to the method, inverse solution is carried out on all machining postures, exhaustive calculation is carried out on all moving tracks, all the tracks are calculated and the sequence is weighted, an optimal moving track is obtained, and after calculation is completed, a coordinate set file is generated. When the same workpiece is machined, the file is loaded, and workpiece production can be started.

Description

Technical Field

[0001] The present invention relates to the technical field of machining, and particularly to a method for calculating the trajectory of a robotic arm for a matrix of evenly distributed cylindrical objects at specific points. Background Art

[0002] With the progress of technology and the rapid development of productivity, robots are playing an increasingly important role in contemporary society. In current industrial production, industrial robotic arms have been widely used.

[0003] The control system of existing robotic arms is a non-linear open-loop control system. During the actual control of the robotic arm, it is affected by parameter uncertainties and non-linear disturbances, resulting in a decrease in the trajectory accuracy of the robotic arm. In order to improve the trajectory accuracy of the robotic arm, on the one hand, the self-learning ability of multi-layer neural networks and robust sliding mode techniques are used to weaken the influence of model uncertainties in the control system on the control accuracy; on the other hand, the robotic arm model is calibrated by integrating sensor algorithms to improve the parameter accuracy of the robotic arm model, thereby improving the control accuracy of the robotic arm.

[0004] However, after each modification by the above methods, the robotic arm model needs to be recalibrated, which significantly shortens the service life of the robotic arm and reduces its working efficiency. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for calculating the trajectory of a robotic arm for a matrix of evenly distributed cylindrical objects at specific points, aiming to solve the problem that after each modification of controlling the robotic arm in the prior art, the robotic arm model needs to be recalibrated, which significantly shortens the service life of the robotic arm and reduces its working efficiency.

[0006] To achieve the above purpose, the present invention provides a method for calculating the trajectory of a robotic arm for a matrix of evenly distributed cylindrical objects at specific points, including the following steps:

[0007] Import the workpiece model into the control system and set the positions of the workpiece processing points;

[0008] Calculate the position coordinates of the robotic arm flange based on the section coordinates of the processing point positions, and inversely calculate the rotation angle of each axis of the robotic arm flange;

[0009] Generate a set of robotic arm postures for all processing points based on the position coordinates of the robotic arm flange and the axis rotation angles, and calculate the total absolute value of the change of all axes and the variance of the change of each group of axes of the original axes respectively;

[0010] Sort and weight the total absolute value and the axis change variance to obtain the final sorting score, and obtain the processing position postures of two points of the final sorting score;

[0011] Calculate the machining position postures of the two adjacent points based on the behavior unit in sequence, obtain the robotic arm posture change array, and verify the robotic arm posture change array to obtain the workpiece machining path.

[0012] Among them, the specific method for importing the workpiece model into the control system and setting the workpiece machining points:

[0013] Model the workpiece to be machined using 3D design software to obtain the workpiece model;

[0014] Import the workpiece model into the control system and set the workpiece machining points.

[0015] Among them, the specific method for calculating the position coordinates of the robotic arm flange based on the machining point position section coordinates and inversely calculating the rotation angle of each axis of the robotic arm flange:

[0016] Based on the machining point position section coordinates, calculate the position coordinates of the robotic arm flange when the longitudinal position of each machining point coincides with the starting position;

[0017] Inversely calculate the rotation angle of each axis of all postures of the robotic arm flange in the current state.

[0018] Among them, the specific method for sorting, weighting the absolute value total and the axis change variance to obtain the final sorting score, and obtaining the machining position postures of the two points of the final sorting score:

[0019] Sort the absolute value total and the axis change variance respectively, and sort the sorting order of the absolute value total and the sorting order of the axis change variance from small to large and weight them to obtain the final sorting score;

[0020] Based on the two original joint coordinates of the minimum value of the final sorting score, obtain the machining position postures of the two points.

[0021] Among them, the specific method for calculating the machining position postures of the two adjacent points based on the behavior unit in sequence, obtaining the robotic arm posture change array, and verifying the robotic arm posture change array to obtain the workpiece machining path:

[0022] Calculate the machining position postures of the two adjacent points based on the behavior unit in sequence to obtain the robotic arm posture change array;

[0023] Import the robotic arm posture change array into the control system for operation, and monitor the position and posture of the robotic arm in real time through a sensor or a vision system to obtain the monitoring data;

[0024] Verify and compare the monitored data with the planned target points. If a deviation is found, stop the control system for adjustment and optimization until the verification is correct to obtain the workpiece processing path.

[0025] Among them, the control system includes a robotic arm, a turntable, and a computer, and the computer is respectively connected to the robotic arm and the turntable.

[0026] Among them, the turntable includes a drive motor, a rotating disk, and a fixed clamp. The rotating disk is fixedly connected to the output end of the drive motor and is located on top of the drive motor. The fixed clamp is arranged on the side of the rotating disk away from the drive motor.

[0027] A method for calculating the robotic arm trajectory of a matrix of evenly distributed cylindrical objects in the present invention. Import the workpiece model into the control system and set the positions of the workpiece processing points. Calculate the position coordinates of the robotic arm flange based on the section coordinates of the processing point positions, and inversely calculate the rotation angles of each axis of the robotic arm flange. Generate a set of robotic arm postures for all processing points based on the position coordinates of the robotic arm flange and the axis rotation angles, and calculate the total absolute value of the changes of all axes and the variance of each group of axis changes of the original axes respectively. Sort and weight the total absolute value and the axis change variance to obtain the final sorting score, and obtain the processing position postures of two points with the final sorting score. Calculate the processing position postures of the two points of adjacent points based on the behavior unit in sequence to obtain an array of robotic arm posture changes, and verify the array of robotic arm posture changes to obtain the workpiece processing path. This method utilizes the performance of the computer to perform inverse solutions for all processing postures, then exhaustively calculates all movement trajectories, obtains the optimal movement trajectory by calculating each trajectory and weighting the sorting. After the calculation is completed, a coordinate set file will be generated. When processing the same workpiece later, loading this file can start the workpiece production, solving the problem that in the prior art, after each modification of the robotic arm control, it is necessary to recalibrate the robotic arm model, greatly shortening the service time of the robotic arm and reducing the working efficiency of the robotic arm. Description of the Drawings

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0029] Figure 1 It is a flowchart of a method for calculating the robotic arm trajectory of a matrix of evenly distributed cylindrical objects provided by the present invention.

[0030] Figure 2It is a flowchart of the specific method for importing a workpiece model into a control system and setting the machining point positions of the workpiece.

[0031] Figure 3 It is a flowchart of the specific method for calculating the position coordinates of the robotic arm flange based on the sectional coordinates of the machining point positions and inversely calculating the rotation angles of each axis of the robotic arm flange.

[0032] Figure 4 It is a flowchart of the specific method for sorting, weighting the total absolute value and the variance of axis changes to obtain the final sorting score, and obtaining the machining position postures of two points corresponding to the final sorting score.

[0033] Figure 5 It is a flowchart of the specific method for sequentially calculating the machining position postures of two adjacent points based on the behavioral units, obtaining the robotic arm posture change array, and verifying the robotic arm posture change array to obtain the workpiece machining path.

[0034] Figure 6 It is a schematic diagram of the workpiece placed on the turntable.

[0035] Figure 7 It is a flowchart of a method for calculating the robotic arm trajectory of a matrix of evenly distributed cylindrical objects provided by the present invention.

[0036] Figure 8 It is a schematic diagram of the robotic arm of the control system provided by the present invention.

[0037] Figure 9 It is a schematic connection diagram of the control system provided by the present invention.

[0038] Figure 10 It is a schematic diagram of the turntable structure of the control system provided by the present invention.

[0039] In the figure: 1 - robotic arm, 2 - turntable, 3 - computer, 4 - drive motor, 5 - rotating disk, 6 - fixed clamp, 7 - clamping plate, 8 - telescopic cylinder, 9 - buffer rod, 10 - damping rod, 11 - buffer spring. Specific Embodiments

[0040] The following details the embodiments of the present invention. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, and should not be construed as limiting the present invention.

[0041] Please refer to Figures 1 to 10 , the present invention provides a method for calculating the robotic arm trajectory of a matrix of evenly distributed cylindrical objects, including the following steps:

[0042] S1 Import the workpiece model into the control system and set the workpiece processing point position;

[0043] Specific method:

[0044] S11 Use 3D design software to model the workpiece to be processed to obtain the workpiece model;

[0045] S12 Import the workpiece model into the control system and set the workpiece processing point positions.

[0046] In the embodiment of the present invention, let the names of the n processing point positions in the first row be an0, the names of the m rows in the first column be a0m, and the layer heights of the matrix from layer 0 to layer m be h0 to h m , and the processing angles of each layer be α0 to α m . When the processing angle of the nth layer cannot be divided evenly by 360, the control system will give a prompt for uneven processing of this row.

[0047] S2 Calculate the position coordinates of the robotic arm flange based on the sectional coordinates of the processing point position, and back-calculate the rotation angle of each axis of the robotic arm flange;

[0048] Specific method:

[0049] S21 Calculate the position coordinates of the robotic arm flange when the longitudinal position of each processing point coincides with the starting position based on the sectional coordinates of the processing point position;

[0050] In the embodiment of the present invention, through the sectional coordinates of the processing point position surface, calculate the position coordinates [x mn , y mn , z mn , a mn , b mn , c mn of the robotic arm flange when the longitudinal position of each processing point coincides with the starting position.

[0051] S22 Back-calculate the rotation angle of each axis of all postures of the robotic arm flange in the current state.

[0052] In the embodiment of the present invention, back-calculate the rotation angle of each axis of all postures of the robotic arm flange in the current state and convert it to the range of -180° to 180°. Assume that processing the flange position of a00 point will back-solve j kinds of coordinates, then the coordinate points of the jth kind of coordinates are [J1 00j, J2 00j, J3 00j, J4 00j, J5 00j, J6 00j , and finally generate an angle set and store it in the memory.

[0053] S3 generates a set of robot arm postures for all machining points based on the position coordinates of the robot arm flange and the axis rotation angles, and calculates the total absolute value of the changes of all axes and the variance of each group of axis changes of the original axes respectively;

[0054] In the embodiment of the present invention, all the robot arm postures of all machining points are generated and put into a set. Subsequently, starting from the first point a00, taking one line as a group, calculate the movement trajectories of adjacent two machining points, such as the angle set of a00 and a01, and calculate the total value S of the absolute values of the changes of all axes corresponding to all points respectively mnm(n+1)jk , for example, calculate the j-th joint coordinate [J1 mnj, J2 mn0j, J3 mnj, J4 mnj, J5 mnj, J6 mnj of the point amn and the k-th joint coordinate [J1 m(n+1)k, J2 m(n+1)k, J3 m(n+1)k, J4 m(n+1)k, J5 m(n+1)k, J6 m(n+1)k of am(n + 1) with the formula:

[0055]

[0056] Then calculate the variance of each group of axis change values of the original axes in this order:

[0057]

[0058] S4 sorts and weights the total absolute value and the axis change variance to obtain the final sorting score, and obtains the machining position postures of two points of the final sorting score;

[0059] Specific method:

[0060] S41 sorts the total absolute value and the axis change variance respectively, and sorts the sorting order of the total absolute value and the sorting order of the axis change variance in ascending order and weights them to obtain the final sorting score;

[0061] In the embodiment of the present invention, the total value S mnm(n+1)jk calculated from the two groups of values and the variance σ mnm(n+1)jk 2 are sorted respectively, and the sorting order of the total value and the sorting order of the variance are sorted in ascending order, and the obtained orders are weighted by 0.5 respectively to obtain the final sorting score.

[0062] S42 obtains the machining position postures of two points based on the two original joint coordinates with the minimum final sorting score.

[0063] In the embodiment of the present invention, the two original joint coordinates that obtain the minimum score based on the final sorting score are considered to be the optimal postures of the processing positions of the front and rear two points of this group.

[0064] S5 Calculate the postures of the two-point processing positions of adjacent points in sequence based on the behavior unit, obtain the robotic arm posture change array, and verify the robotic arm posture change array to obtain the workpiece processing path.

[0065] Specific method:

[0066] S51 Calculate the postures of the two-point processing positions of adjacent points in sequence based on the behavior unit to obtain the robotic arm posture change array;

[0067] In the embodiment of the present invention, calculate the optimal change postures of adjacent points in sequence according to the behavior unit, finally obtain a set of robotic arm posture change arrays, and recognize them as the optimal processing path of the workpiece.

[0068] S52 Import the robotic arm posture change array into the control system for operation, and real-time monitor the position and posture of the robotic arm through a sensor or a vision system to obtain monitoring data;

[0069] S53 Verify and compare the monitoring data with the planned target points. If a deviation is found, stop the control system for adjustment and optimization until the verification is correct to obtain the workpiece processing path.

[0070] Further, the control system includes a robotic arm 1, a turntable 2, and a computer 3. The computer 3 is respectively connected to the robotic arm 1 and the turntable 2. The turntable 2 includes a driving motor 4, a rotating disk 5, and a fixing clamp 6. The rotating disk 5 is fixedly connected to the output end of the driving motor 4 and is located on the top of the driving motor 4. The fixing clamp 6 is arranged on the side of the rotating disk 5 away from the driving motor 4.

[0071] In the embodiment of the present invention, the computer 3 is used to import workpiece parameters into 3D design software, model the workpiece to be processed, perform inverse kinematics on all processing postures, then perform exhaustive calculations on all movement trajectories, obtain the optimal movement trajectory by calculating each trajectory and weighting the sorting. After the calculation is completed, a coordinate set file will be generated. The turntable 2 is used to place the workpiece to be processed and rotate the workpiece under the control of the computer 3. The robotic arm 1 is used to process the workpiece. Specifically, the computer 3 controls the fixing clamp 6 to clamp and fix on the turntable 2, and starts the driving motor 4 to drive the turntable 2 to rotate.

[0072] Further, the fixing clamp 6 includes a clamping plate 7, a telescopic cylinder 8 and a buffer rod 9. The telescopic cylinder 8 is fixedly connected to the rotating disk 5 and is located at the top of the rotating disk 5. The clamping plate 7 is fixedly connected to the telescopic cylinder 8 and is located on one side of the telescopic cylinder 8. The buffer rod 9 is fixedly connected to the clamping plate 7 and is also fixedly connected to the rotating disk 5 and is located on one side of the telescopic cylinder 8.

[0073] In the embodiment of the present invention, the telescopic cylinder 8 is controlled to extend and retract by the computer 3, so as to push the clamping plate 7 close to the workpiece to be processed. The buffer rod 9 is provided to buffer the acting force of the telescopic cylinder 8 and avoid damaging the workpiece to be processed due to excessive acting force of the telescopic cylinder 8.

[0074] Further, the buffer rod 9 includes a damping rod 10 and a buffer spring 11. The damping rod 10 is fixedly connected to the clamping plate 7 and is also fixedly connected to the rotating disk 5 and is located on one side of the telescopic cylinder 8. The buffer spring 11 is sleeved outside the damping rod 10.

[0075] In the embodiment of the present invention, the damping rod 10 provides a buffer medium inside it to achieve the purpose of buffering the acting force of the telescopic cylinder 8. The buffer spring 11 is provided to enhance the buffering effect of the damping rod 10 on the acting force of the telescopic cylinder 8.

[0076] What is disclosed above is only a preferred embodiment of a method for calculating the trajectory of a robotic arm for a uniform cylindrical object matrix point position of the present invention. Of course, the scope of the rights of the present invention cannot be limited by this. Those of ordinary skill in the art can understand all or part of the processes of implementing the above embodiments, and the equivalent changes made according to the claims of the present invention still fall within the scope covered by the invention.

Claims

1. A method for calculating the trajectory of a robotic arm at the matrix points of a uniform cylindrical object, characterized in that, It includes the following steps: Import the workpiece model into the control system and set the workpiece processing point position; Calculate the position coordinates of the robotic arm flange based on the section coordinates of the processing point position, and inversely calculate the rotation angle of each axis of the robotic arm flange; Generate a set of robotic arm postures for all processing points based on the position coordinates of the robotic arm flange and the axis rotation angles, and calculate the total absolute value of all axis changes and the variance of each group of axis changes of the original axes respectively; Sort and weight the total absolute value and the axis change variance to obtain the final sorting score, and obtain the machining position postures of two points of the final sorting score; Calculate the machining position postures of the two points of adjacent points in sequence based on the behavior unit to obtain the robotic arm posture change array, and verify the robotic arm posture change array to obtain the workpiece machining path.

2. The robotic arm trajectory calculation method for the matrix points of a uniform cylindrical object according to claim 1, characterized in that; The specific method for importing the workpiece model into the control system and setting the workpiece machining point positions: Model the workpiece to be machined using 3D design software to obtain the workpiece model; Import the workpiece model into the control system and set the workpiece machining point positions.

3. The robotic arm trajectory calculation method for the matrix point positions of uniform cylindrical objects as described in claim 1, Characterized in that; The specific method for calculating the position coordinates of the robotic arm flange based on the section coordinates of the processing point position and inversely calculating the rotation angle of each axis of the robotic arm flange: Based on the section coordinates of the processing point position, calculate the position coordinates of the robotic arm flange when the longitudinal position of each processing point coincides with the starting position; Inversely calculate the rotation angle of each axis of all postures of the robotic arm flange in the current state.

4. The robotic arm trajectory calculation method for the matrix points of a uniform cylindrical object according to claim 1, characterized in that; The specific method for sorting, weighting the total absolute value and the axis change variance to obtain the final sorting score, and obtaining the machining position postures of two points of the final sorting score: Sort the total absolute value and the axis change variance respectively, and sort the sorting order of the total absolute value and the sorting order of the axis change variance from small to large and weight them to obtain the final sorting score; Based on the two original joint coordinates of the minimum value of the final sorting score, obtain the machining position postures of two points.

5. The robotic arm trajectory calculation method for the matrix point positions of uniform cylindrical objects as described in claim 1, Characterized in that; The specific method for calculating the machining position postures of the two points of adjacent points in sequence based on the behavior unit to obtain the robotic arm posture change array, and verifying the robotic arm posture change array to obtain the workpiece machining path: Calculate the machining position postures of the two points of adjacent points in sequence based on the behavior unit to obtain the robotic arm posture change array; Import the robotic arm posture change array into the control system for operation, and monitor the position and posture of the robotic arm in real time through a sensor or a vision system to obtain monitoring data; Verify and compare the monitoring data with the planned target points. If a deviation is found, stop the control system for adjustment and optimization until the verification is correct to obtain the workpiece machining path.

6. The manipulator trajectory calculation method for the matrix point positions of uniform cylindrical objects as described in claim 1, characterized in that ； The control system includes a robotic arm, a turntable and a computer, and the computer is respectively connected to the robotic arm and the turntable.

7. The manipulator trajectory calculation method for the matrix point positions of uniform cylindrical objects as described in claim 6, wherein ； The turntable includes a driving motor, a rotating disk, and a fixing clamp. The rotating disk is fixedly connected to the output end of the driving motor and is located above the driving motor. The fixing clamp is arranged on the side of the rotating disk away from the driving motor.

Images