Electro-mechanical feedback for realization of a mechanical spectrum analyzer

TitleElectro-mechanical feedback for realization of a mechanical spectrum analyzer
Publication TypeConference Paper
Year of Publication2003
AuthorsCretu, E., L. A. Rocha, and R. F. Wolffenbuttel
Conference NameTransducers, Solid-State Sensors, Actuators and Microsystems, 12th International Conference on, 2003
Pagination1407 - 1410 vol.2
Date Publishedjun.
Keywordsactuation capacitors, capacitors, driving electrical frequency, electrically controlled signal, electro-mechanical feedback, functional coupling, harmonic common mode voltage, intrinsic nonlinear coupling, MEMS, microactuators, microdomain, monitoring equipment, real time mechanical spectrum analyzer, spectral analysers, surface micromachined accelerometer, time multiplexed signal processing, twin-accelerometer scheme, voltage controlled gain

An important feature of MEMS, still underutilized, is the tight coupling between the electrical and mechanical quantities in the micro domain. This paper demonstrates the benefits of such a functional coupling for a specific device: a real-time mechanical spectrum analyzer. A surface micromachined accelerometer was designed, with a voltage-controlled gain. By applying an harmonic common-mode voltage on the actuation capacitors, the intrinsic nonlinear coupling performs a correlation between the input acceleration and an electrically-controlled signal. To reduce the distortion, a differential, twin-accelerometer scheme is used. Time-multiplexed signal processing gives both the real and the imaginary components of the selected spectral line. A mechanical spectrum analyzer for low-frequency domains is obtained when the driving electrical frequency is swept over the range of interest. The operating principle has been confirmed by measurements, and is expected to yield new opportunities in the field of low-power, low-cost condition monitoring equipment.


a place of mind, The University of British Columbia

Electrical and Computer Engineering
2332 Main Mall
Vancouver, BC Canada V6T 1Z4
Tel +1.604.822.2872
Fax +1.604.822.5949

Emergency Procedures | Accessibility | Contact UBC | © Copyright 2021 The University of British Columbia