Fuzzy tuning PI control for initial levitation of micromachined electrostatically levitated gyroscope

A novel microgyroscope based on UV-LIGA technology is described, in which the wheel-like rotor is levitated and rotated by the electrostatic forces. A simple fuzzy logic scheme for online tuning of PI (proportional integral) controller parameters to improve system robustness of initial levitation is outlined. Experimental results indicate that, with fuzzy tuning, the overshoot is reduced to 17% compared with 27% of the conventional PI controller. The rise time for the two channels of the four is 3.6 ms and the settle time is nearly 25.6 ms, which shows a quick response time and good steady-state performance. From the experiment of 0.5 g pulse acceleration input, sensitivity along axial direction is 1 V g when it acts as an accelerometer.