Milling machining robot attitude optimizing method and device considering minimum contour error

Abstract

The invention belongs to the field of robot milling machining and discloses a milling machining robot attitude optimizing method and device considering the minimum contour error. The method comprisesthe following steps that S1, the cutting force simulation of a cutting process is carried out according to a to-be-machined workpiece and the path of a cutter, and cutting force data at a discrete cutter location point are obtained; S2, the cutter location point data under a workpiece coordinate system are converted into the cutter location point data under the robot base coordinate system; S3, equal interval division is carried out on all cutter location points within the feasible range of the cutter shaft angles; S4, the nose point deviation at each cutter shaft angle is calculated; S5, thecutter location point contour error of the cutter milling machining is calculated; S6, for a single cutter location point, the robot attitude corresponding to the minimum cutter location point contourerror in all the cutter shaft angles is searched for under a given limit and constraint condition, and the robot attitude with the minimum cutter location point contour error is obtained; and S7, thesixth step is carried out on all the cutter location points, and the milling machining robot attitude with the minimum contour error is obtained.

Description

technical field [0001] The invention belongs to the field of robot milling processing, and relates to a method and equipment for optimizing the posture of a milling robot considering the minimum contour error, and more specifically, to a robot posture optimization calculation method for considering the optimal contour error of processing engineering in robot milling processing . Background technique [0002] In the field of robot milling, the most important factor affecting the quality of the workpiece is the machining error caused by the end deformation caused by the low rigidity of the robot and the milling force, without considering the error of the robot's motion accuracy. For six-degree-of-freedom serial industrial robots, the problem of low stiffness is a common problem, and its stiffness distribution is heavily dependent on the robot's attitude. [0003] In order to solve the above problems, some scholars proposed a robot structural stiffness performance index that h...

AI Technical Summary

Problems solved by technology

[0004] 1. Since this method does not consider the end execution force of the robot, it cannot guarantee the maximum rigidity of the robot in the force direction;

[0005] 2. This method can ensure the minimum displacement deviation of the tool tip point, but since the error of the end position of the robot is generally greater than the contour error, this method cannot guarantee the minimum contour error after machining

[0007] 1. This method does not consider the pre-planning and control of the robot’s terminal position and posture. The purpose is only to ensure that the robot’s terminal position is consistent with the planned position through closed-loop feedback during the processing process; therefore, this method is also a real-time error control of the terminal position, and cannot Ensure the minimum contour error after processing;

[0008] 2. Since the consideration of the static stiffness of the robot in this method is only reflected in the selection of the workpiece position, the workpiece position is not changed during the machining process, and the influence of the cutting force on the stiffness during milling is not considered. Therefore, it is still not possible for machining Errors caused by variations in robot stiffness during the process are compensated for

[0009] It can be seen that the calculation and compensation of the deformation of the robot end in the prior art do not take into account the problem of robot attitude selection in the process of robot milling, nor optimize the contour error, which makes it difficult to further improve the quality of robot milling

Images