Richard Balogh

We document a feedback controller design for a nonlinear electrostatic transducer that exhibits a~strong unloaded resonance. Challenging features of this type of transducer include the presence of multiple fixed points (some of which are unstable), nonlinear force-to-deflection transfer, effective spring-constant softening due to electrostatic loading and associated resonance frequency shift. Furthermore, due to the utilization of low-pass filters in the electronic readout circuitry, a significant amount of transport delay is introduced in the feedback loop.