Self-sustained micromechanical oscillator with linear feedback

TL;DR

This paper introduces a novel self-sustained micromechanical oscillator where the nonlinearity is inherent to the resonator, enabling stable oscillations with linear feedback, validated through experiments on a MEMS device.

Contribution

It presents a new self-sustaining scheme where the resonator's nonlinearity, not the feedback, limits amplitude, differing from traditional designs.

Findings

Model accurately describes the oscillator's behavior

Experimental validation on MEMS device confirms the theory

Stable oscillations achieved with linear feedback

Abstract

Autonomous oscillators, such as clocks and lasers, produce periodic signals \emph{without} any external frequency reference. In order to sustain stable periodic motions, there needs to be external energy supply as well as nonlinearity built into the oscillator to regulate the amplitude. Usually, nonlinearity is provided by the sustaining feedback mechanism, which also supplies energy, whereas the constituent resonator that determines the output frequency stays linear. Here we propose a new self-sustaining scheme that relies on the nonlinearity originating from the resonator itself to limit the oscillation amplitude, while the feedback remains linear. We introduce a model to describe the working principle of the self-sustained oscillations and validate it with experiments performed on a nonlinear microelectromechanical (MEMS) based oscillator.