Automatic Hysteresis Modeling of Piezoelectric Micromanipulator in Vision-Guided Micromanipulation Systems

Conventional hysteresis modeling of piezoelectric actuators using interferometers or capacitive sensors is often performed off-line. However, the hysteresis of the piezoelectric actuator changes as the load acting on it or the driving frequency of the input signal alters, demanding that the hysteresis of the micromanipulator be modeled on the fly. The employment of interferometers or capacitive sensors is a challenging task in micromanipulation systems due to their special requirements, e.g., the micropipette tip is desired to provide mirror-like reflection of the incoming beam if an interferometer is employed while a capacitive sensor might not be easily placed in the workspace. An automatic Prandtl-Ishlinskii hysteresis modeling method is proposed and implemented using vision-feedback. The method can be conducted on the fly in real time making it suitable for time critical vision-guided micromanipulation, while providing comparable accuracy with that of using interferometers.