Diagnosis of operational changes in microelectromechanical systems via fault detection

Abstract

As microelectromechanical systems (MEMS) devices migrate into progressively more critical systems, the reliability these devices have to demonstrate must increasingly improve. Current research in the reliability of MEMS has succeeded in increasing the reliability of commercialized MEMS before they are integrated into an application by focusing on fabrication processes, device materials, and packaging. In this study, the focus is on assessing the reliability of MEMS during device operation. A fault detection approach was taken to diagnose incipient changes in the operation of MEMS devices. Model-based fault detection schemes utilizing the Kalman filter and H ∞ filter as residual generators were investigated. Analysis of the residual was conducted using a discrete Fourier transform (DFT). Two common MEMS research devices, the lateral comb resonator and parallel plate actuator, are used to demonstrate theoretically and experimentally the ability of the fault detectors to identify induced faults in linear and nonlinear domains of system operation. v 3.3.1 Extended Kalman Filter Results .

Diffractive optical lens design and fabrication for integrated monitoring of microelectromechanical lateral comb resonators

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