Industrial robot absolute precision calibration system and calibration method

Abstract

The invention discloses an industrial robot absolute precision calibration system and calibration method. The calibration system comprises a three-ball base device, an end measuring device, a robot, acommunication cable, a computer and the like, and the calibration method comprises the steps that the fixed three-ball base device is used for building a world coordinate system used for describing arobot base coordinate system; the end measuring device mounted on a robot flange is used for measuring robot end position error information; the computer is used for reading position error data and robot joint angle data; and finally, all measured data are substituted into an absolute accuracy calibration algorithm of the computer to carry out iterative computation, and an exact kinematic model describing the world coordinate system is obtained. The calibration system and the calibration method are used, the posture of the robot base coordinate system and robot kinematics parameters can be accurately calibrated, and the robot absolute positioning precision can be improved.

Description

technical field [0001] The present invention relates to a robot calibration method, in particular to an industrial robot absolute precision calibration system and calibration method, at least used to realize the calibration of robot base coordinate system pose and robot body kinematics parameters, belonging to the field of robot kinematics calibration. Background technique [0002] With the development of robot application technology, manufacturing enterprises have higher and higher application requirements for industrial robot offline programming technology, especially in automobile manufacturing, aviation manufacturing and other industries. At present, industrial robots usually have high repeatability positioning accuracy, but their absolute positioning accuracy is low, which is mainly caused by the error of robot kinematics parameters and the difficulty of precise positioning of the robot base coordinate system, which affects the offline programming operations. reliabilit...

AI Technical Summary

Problems solved by technology

However, most of the existing new robot calibration methods are aimed at the calibration of the kinematic parameters of the robot body, which is a relative calibration method, so it is impossible to accurately calibrate the robot base coordinate system.

[0005] In the field of robot kinematics calibration research, CN107042528A discloses an industrial robot calibration system and method. The calibration system mainly includes an end effector on the robot and two movable target spheres with a fixed center distance. The error between the nominal distance and the actual distance establishes a calibration algorithm to realize the calibration of the kinematic parameters of the robot body, but the calibration algorithm uses the distance error model, which belongs to the relative calibration method, and the reliability of the calibration results is limited. Unable to calibrate the exact position of the robot base coordinate system

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