Robot absolute positioning accuracy calibration method based on kinematics and spatial interpolation

Abstract

The invention relates to a method for calibrating absolute positioning accuracy of a robot based on kinematics and spatial interpolation, and belongs to the field of robot control methods. First, a geometric parameter error model and a compliance error model of the robot are respectively established to obtain a quantifiable error ΔV; then, the robot is measured. The actual end pose, obtain the identification experimental data, use the EKF algorithm to identify the robot's quantitatively calculated error ΔV parameter, and use the robot error parameters obtained by identification to correct the robot's nominal geometric parameters, that is, the first positioning error compensation of the robot is completed, and the remaining The robot positioning residual error; the robot positioning residual error model is then constructed; finally, the second positioning error compensation of the robot is performed; finally, the desired position of the robot is obtained. The invention establishes a variable node distance interpolation algorithm considering the degree of joint influence, which can effectively improve the absolute positioning accuracy of the robot and improve the accuracy of the existing methods and technologies.

Description

technical field [0001] The invention belongs to the field of robot control methods, in particular to a method for calibrating absolute positioning accuracy of a robot based on kinematics and spatial interpolation, in particular to an absolute positioning accuracy error compensation method for industrial robots used for grinding, milling and other mechanical processing. Background technique [0002] Industrial robots are mostly spatial six-axis series mechanisms. Compared with CNC machine tools, they have the advantages of high processing flexibility, low cost and large working space. Therefore, they are more and more used in the field of mechanical processing, especially with a variety of varieties. Workpieces with features such as small batches and larger structures. However, the absolute positioning accuracy of industrial robots is poor (generally greater than 0.1mm), resulting in low robot position control accuracy, and it is difficult to achieve precise contact between t...

AI Technical Summary

Problems solved by technology

However, there are many sources of robot positioning errors, including non-geometric parameters with strong nonlinear and coupling characteristics such as gear clearance, mass distribution of the manipulator, load changes, and thermal effects, so it is difficult to build an accurate mapping model

At the same time, most studies also did not consider the structural characteristics and motion characteristics of multi-joint robots, as well as the distribution characteristics and action rules of robot pose errors.

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