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

Abstract

The invention discloses a robot absolute positioning precision calibration method based on kinematics and spatial interpolation, and belongs to the field of robot control methods. The method comprises the following steps: firstly, respectively establishing a robot geometric parameter error model and a flexibility error model to obtain a quantitative calculation error delta V; then, measuring an actual tail end pose of the robot to obtain identification experiment data, adopting an EKF algorithm for robot quantitative calculation error delta V parameter identification, correcting robot nominal geometric parameters through robot error parameters obtained through identification, thereby accomplishing first-time positioning error compensation of the robot and remaining robot positioning residual errors; constructing a robot positioning residual error model; carrying out secondary positioning error compensation on the robot; and finally obtaining an expected position of the robot. A variable-node distance interpolation algorithm considering joint influence degree is established, so that absolute positioning precision of the robot can be effectively improved, and defects of an existing method and technology in precision are overcome.

Description

technical field [0001] The invention belongs to the field of robot control methods, and in particular relates to a robot absolute positioning accuracy calibration method based on kinematics and space 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 work space. Therefore, they are more and more used in the field of mechanical processing, especially with multi-variety Workpieces with characteristics such as small batches and large 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 the end...

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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