Research and experiment on coordinated tracking of turntable in robot turning body machining

Different from NC machining, robot can process large-scale and complex products by expanding external axis. In this paper, the method of tracking robot's motion by turntable is studied, and the robot's machining of the rotating body is realized. Firstly, the tool path is generated by software, and the generated tool path is linearly interpolated. The space point coordinates after interpolation are post processed and assigned to the robot to generate the robot's trajectory, while the angle after interpolation is assigned to the turntable. Kalman filter is used to predict the movement time of the robot's adjacent trajectory points, and the time is assigned to the turntable to realize the turntable's coordinated tracking of the robot's movement. Secondly, according to the chord height of the adjacent track points, the chord height interpolation of the track points is carried out to further improve the tracking accuracy of the turntable. The experimental results show that the average angle error of the turntable is -0.121°~0.086°after linear interpolation. After the chord height interpolation, the radial trajectory error is reduced from 1 mm to 0.1 mm.