Lyapunov based adaptive control of a MEMS gyroscope

We present an adaptive controller to control all modes of a vibrational MEMS gyroscope. Our controller tunes the natural frequency of the drive axis, regulates the amplitude of the drive axis vibration, cancels out quadrature error due to stiffness coupling, and drives the sense axis vibration to zero in force-to-rebalance mode. We use both feedforward and feedback control. We simulate this controller for the Berkeley Z-axis gyro. The Lyapunov function used has a critical effect on the system response time, especially for the force-to-rebalance and automatic gain control loops.