A Calibration Method of Industrial Robot Kinematic Parameters Based on Linear Displacement Sensor

Abstract

The invention discloses an industrial robot kinematic parameter calibration algorithm based on a linear displacement sensor, which belongs to the technical field of robots. According to the algorithm, the sensor can be fixed at a position in working space of the robot, the robot moves to a different specified position according to a teaching program instruction and stops, the distance data between the tail end TCP of the robot and the reference position of the sensor can be acquired via the sensor, and a joint angle value is recorded; then, rough calibration is carried out, the robot TCP is used for acquiring the initial value of the reference position of the sensor, a more accurate value of the reference position of the sensor is acquired according to the measurement data and a calibration equation, the calibration equation is obtained when zero variation of the joint angle is only considered, and rough calibration is completed; and fine calibration is carried out, all DH parameters of the robot, tail end connection rod parameters and the sensor zero variation are considered, a calibration equation is built, and calibration is completed after multiple iterations. The industrial robot kinematic parameter calibration algorithm based on the linear displacement sensor has the advantages of simple structure, easy realization, high calibration precision, quick convergence speed and the like.

Description

Technical field: [0001] The invention belongs to the technical field of robots, and in particular relates to a method for calibrating kinematic parameters of an industrial robot based on a linear displacement sensor. Background technique: [0002] With the continuous expansion of the application range of industrial robots and the complexity of their tasks in industrial production, the requirements for the position and attitude accuracy of industrial robots are also getting higher and higher. At present, industrial robots have a high repeat positioning accuracy, within 0.1mm, but the absolute positioning accuracy is very low, above 1mm, or even 1cm, which severely limits the application range of industrial robots. Many reasons lead to low positioning accuracy of industrial robots, the most important of which is the parameter deviation of the geometric structure in the kinematics model. Calibration technology is an effective method to compensate for these parameter deviations...

AI Technical Summary

Problems solved by technology

However, due to the characteristics of the linear displacement sensor itself, such as low accuracy compared to the laser tracker, the measurement data is one-dimensional (only the distance between two points can be measured), etc., which limit its application in the field of robot calibration, so It is an urgent need to develop a calibration method for robot kinematics parameters based on linear displacement sensors

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