Remarks on tracking and robustness analysis for MEM relays

We announce a new class of tracking controllers, applicable to both electrostatic and electromagnetic microelectromechanical (MEM) relays, that yield arbitrarily fast local exponential convergence of the tracking error to zero and uniform global asymptotic stability of the error dynamics. Our stability analysis is based on an explicit, strict, global Lyapunov function construction. Our Lyapunov approach also leads to an input-to-state stability based quantification of the effects of parametric uncertainty on the tracking performance. The MEM dynamics contain a quadratic nonlinearity that leads to constraints on the class of reference trajectories that can be tracked. We illustrate how to craft a reference trajectory that is compatible with these constraints and with a typical opening and closing relay operation. Our simulation indicates the good tracking performance of our controllers.