Calibration method of connecting rod parameters of industrial robot based on end-point plane constraint

Abstract

The invention belongs to the field of calibration of connecting rod parameters of an industrial robot, in particular to a calibration method of the connecting rod parameters of the industrial robot based on end-point plane constraint. The calibration method comprises the following steps: (1) establishing a connecting rod coordinate system and a tool coordinate system of the industrial robot, and thus obtaining the end position coordinate of the industrial robot; (2) conducting plane constraint for an end point, and establishing an error identification model of the connecting rod parameters ofthe industrial robot; (3) transforming the postures of the industrial robot, recording the joint values of joint variables and the length of a laser beam, and calculating the initial parameter of a plane equation according to the position coordinates of the first three poses; (4) conducting error identification for the connecting rod parameters of the industrial robot; and (5) correcting parameters to be corrected in order, and verifying the precision of the corrected industrial robot. The calibration method can conduct calibration in the larger working space of the industrial robot, can realize fully automatic calibration, and has high calibration precision and low cost.

Description

Technical field [0001] The invention belongs to the field of the parameter calibration of the connecting rod of an industrial robot, and more specifically relates to a method for calibrating the connecting rod parameter of an industrial robot based on the plane constraint of an end point. Background technique [0002] Robot errors can be divided into two categories: one is geometric parameter errors, which usually refer to errors in which the theoretical and actual values ​​of robot kinematic parameters are inconsistent due to processing, assembly or wear. The other is the non-geometric parameter error, which is caused by the flexibility of the robot transmission system and environmental factors. Its parameters include the stiffness of the joint servo, the stiffness of the connecting rod, the gear gap, and the friction. These errors will result in low pose accuracy at the end of the robot, which cannot meet the high precision requirements of modern industrial production. [0003] ...

AI Technical Summary

Problems solved by technology

[0005] In view of the above defects or improvement needs of the prior art, the present invention provides a method for calibrating the parameters of the connecting rod of an industrial robot based on the plane constraints of the end points, which performs plane constraints on the end points to establish an error identification model of the connecting rod parameters of the industrial robot, And through the laser displacement sensor installed at the end of the industrial robot, the position information of the end point of the industrial robot under different positions and attitudes is obtained, and then the error of the connecting rod parameters of the industrial robot is identified, thereby solving the problem of low precision and automation of the existing calibration methods. It has the characteristics of simple operation, high calibration efficiency and strong practicability.

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