High precision PSD guided robot localization: Design, mapping, and position control

This paper introduces our recently developed high precision robot localization system employing position sensitive detectors (PSD). A lateral effect PSD is an ideal position sensitive device with a resolution of approx. 0.5 mum. Such a device can be used to enhance the precision capabilities of robot localization or robot calibration. The developed PSD guided localization system is comprised of a structured laser pointer system attached to the robot end-effector and a PSD fixture. It is capable of feeding back the movement information of the TCP relative to the PSD frame. This is achieved by detecting the position of the laser beams emitted from the laser pointers onto the PSD surface. The system was well designed, mapped, and constructed and hence allows it to perform precision localization of the robot. Simulations and preliminary experiments demonstrated the effectiveness of the developed PSD guided localization system including hardware, software, and algorithms. Therefore, it is capable of improving the localization performance of robots as well as promoting the application of precision robot calibration.