Robot zero position calibration method based on electromagnetic encoders

Abstract

The invention discloses a robot zero position calibration method based on electromagnetic encoders. The method comprises the steps that the six electromagnetic encoders are installed on six shafts of a robot correspondingly, a coordinate system of the electromagnetic encoders is kept parallel to coordinate systems of the shafts, and by controlling a joint of a base and a shoulder joint to move, two inclination angles and the displacement, namely the reference zero position, of the base are obtained at the same time; and as for other shafts, the coordinate system of the electromagnetic encoders is kept parallel to the coordinate system of the six shafts of the robot, zero positions of other joints are obtained through the recognition method, the difference values of data are stored, all servos are operated according to the difference values, and then the robot can be made to reach the original point position. According to the method, zero position calibration of the whole robot can be achieved through only a few of steps, the zero position alignment precision of the robot can be improved, the operation time of zero position calibration is shortened, influences of vibration and impact are avoided, and the method is suitable for being applied to the robot under severe working conditions.

Description

technical field [0001] The invention belongs to a calibration method for an industrial robot, in particular to a zero-position calibration method for a robot based on an electromagnetic encoder. Background technique [0002] Due to the inevitable error of structural parameters in the process of manufacturing and assembly of the robot, the pose of the end effector produces errors. At the same time, in the actual application of robot operation, the accuracy of the robot will be affected by many reasons such as collision, wear, disassembly and maintenance. Therefore, it is very important to calibrate the structural parameters of the robot to obtain more accurate structural parameter values ​​to improve the pose accuracy of the robot. [0003] Among the factors affecting the absolute positioning accuracy of the robot, the zero position error accounts for as high as 97%, becoming the primary robot error factor to be solved. The robot zero error refers to the relative error valu...

AI Technical Summary

Problems solved by technology

Among the above two methods, although the former method has high precision, it is generally used in scientific research activities due to the complicated operation process and expensive measuring equipment, while the latter method is simple in principle and practical.

[0004] Although the latter method is easy to operate, it needs to process the positioning hole or positioning surface of the robot in advance, and the robot joint needs to be adjusted continuously during calibration. The whole process is very time-consuming and the accuracy is far less than the former method.

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