Adaptive alignment control for a dual-PSD based industrial robot calibration system

Calibration plays an important role in industrial robots. Traditional ways are time consuming and also involve a lot of human efforts. We have proposed a dual-PSD (Position Sensitive Device) method to automatically accomplish the calibration in several minutes. The alignment control problem is the major issue in the calibration process, which requires to move a laser pointer mounted on the robot´s end-effector to shoot the laser beam at one PSD center and reflect to another PSD center. This paper proposes an adaptive control method to solve the alignment problem. It can online estimate the unknown parameters between the robot base frame and the PSD frame, which are usually required before the alignment control. The advantage of the approach is that we do not need to calculate or estimate these parameters before the alignment control so it can further facilitate the automated calibration process. The effectiveness and advantages of the method is demonstrated through simulation results.