User login

O-MEMS accelerometer/gyroscope

Abstract

This project proposes to fabricate Optical Micro-Electro-Mechanical Systems (O-MEMS)for optical acceleration measurements. These would allow for more sensitive, accurate, and reliable measurements, exploiting advantages such as the linear relation between the velocity and the Doppler frequency shift, and the high, wavelength-dependent resolution levels achievable.

Project Description

Accelerometers and gyroscopes are broadly used in the area of vibration sensors. Their applications range from seismic disturbances, to automotive industry applications such as airbag systems, active suspension, and smart braking [1]-[3].

Traditionally the acceleration is detected electrically by measuring the capacitance variation of parallel-plate micro-arrays, or the transformation energy of a piezoelectric material. These electrical methods are considered to have a somewhat low sensitivity and resolution, due to their low signal-to-noise ratio (SNR). Moreover, the linear approximations that are frequently used to model the behaviour of accelerometers and gyroscopes are based on capacitance-variation and are usually poorly justified. This is due to the fact that the displacement of the proof-mass, and therefore that of the (commonly parallel) plate electrodes, is usually of the same length order as is the nominal gap between the electrodes [1], [2].

These difficulties and inaccuracies could be overcome by carrying out laser-based measurements, by exploiting advantages such as the wavelength-dependent spatial resolution and the linear dependence of speed and Doppler frequency shifts.

References

[1] H. Xie and G. Fedder, “Integrated Micromechanical Gyroscopes”, Journal of Aerospace Engineering, 16 (2), pp. 65-75. (April 2003)

[2] D.A. Horsley, R. Horowitz, A.P. Pisano. “Microfabricated Electrostatic Actuators for Hard Disk Drives”, IEEE/ASME Transactions on Mechatronics, 3, (3), pp. 175-183 (September 1998)

[3] A. Bertolini, R. DeSalvo, F. Fidecaro and A. Takamori. “Monolithic folded pendulum accelerometers for seismic monitoring and active isolation systems”, IEEE Nuclear Science Symposium Conference 2004, pp. 4644-4648 (October 2004)

Faculty Supervisor(s)

    Edmond.Cretu    Lukas.Chrostowski    Nicolas.Jaeger   

Researchers(s)

    akhihere    Elie H. Sarraf    mangelgt    MrigankSharma    Robert Boeck    yiyiz   

Research Area(s)