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| Abstract: |
| Industrial robot which can acquire high accuracy has been widely used in automatic assembly. Usually, the geometric parameter of industrial robot should be inspected during manufacturing and application. High precision measurement equipment was utilized to acquire the position and orientation of robot’s end-effector, when calibrating the geometric parameter of robot. A kind of measurement system based on a draw-wire encoder was presented, since the current measurement equipment has some disadvantages, such as the cost and the requirements of working environment are high. According to this kind of measurement system, a sort of geometric calibration method of robot was presented including position and orientation parameters. The uncertain arc length of the cable length between robot end-effector and the measurement can be exactly acquired according to the position and orientation parameters. The pose-solving model of robot end-effector was associated with the kinematic model of robot, and robot’s geometric parameter can be computed by using the least-squares methods. Validate instance was conducted, the result showed that the optimal number of the calibration pose was 47 with little improvement in accuracy, even if increasing the number of calibration pose. Robot calibration experiment was performed and the results showed that the absolute accuracy of robot decreased from 4.32 mm to 0.87 mm after calibration, which improved the robot’s absolute accuracy effectively. |
| Key words: Robot Calibration Industrial robot Geometric parameter identification Robot accuracy Draw-wire encoder |
| DOI：10.11916/j.issn.1005-9113.2023046 |
| Clc Number:TP24 |
| Fund: |
