Control of an Electrostatic Microelectromechanical System Using Static and Dynamic Output Feedback

Abstract

This paper examines control strategies for electrostatically actuated microelectromechanical systems (MEMS), with the goals of using feasible measurements to eliminate the pull-in bifurcation, robustly stabilize any desired operating point in the capacitive gap, decrease settling time, and reduce overshoot. We show that input-output linearization, passivity-based design, and the theory of port-controlled Hamiltonian systems lead naturally to static output feedback of device charge. This formalizes and extends previously reported results from the MEMS literature. Further analysis suggests that significantly improving transient behavior in lightly damped MEMS requires dynamic estimation of electrode velocity. We implement output-feedback control using a reduced-order nonlinear observer. Simulations predict greatly improved transient behavior, and large reductions in control voltage.

Adaptive Control of an Electrostatic Micro-Actuator with Unbounded Dynamic Uncertainties based on Lyapunov Stability Criterion

“…It is appeared from Figure 3 and Figure 4 that the perfect tracking is achieved if control gain (λ) is considered appropriately. Hence, the measure of control gain is suggested 1.1×10 6 . However, this λ must satisfy the limitation of the control effort.…”

“…Therefore, in recent years, different nonlinear controls have been extended to the control of electrostatic microactuator. The some feedback control techniques were developed which those conclude input-output linearization, feedback, and charge feedback schemes [4][5][6][7]. Control schemes based on differential flatness, Lyapunov functions and backstepping control were reported by [11][12][13], respectively.…”

Power–based control of physical systems: two case studies

“…The dynamical equations of motion are given by (Maithripala et al, 2005) (see also (van der Schaft, 2000)). …”

Nonlinear Control Techniques for Micro Electrostatic Actuators in the Presence of Parasitics and Parametric Uncertainties

“…They showed that charge control increased the stable ranges of motion but the maximum stable deflection is limited due to parasitic capacitance and tip-in. Miathripala et al [6] examined control strategies for electrostatically actuated MEMS to eliminate the pull-in bifurcation and stabilized any desired operating points in the capacitive gap. They also showed that significant improvement in transient behavior in lightly damped MEMS requires dynamic estimation of electrode velocity.…”