Fluid effects in vibrating micromachined structure

Abstract

This thesis presents the study of the fluid damping and surfboarding effects for the tuning fork gyroscope. The quality factors in the drive and sense axes will be evaluated and compared with the experimental results for a range of pressures. The effects of the holes and the proof mass thickness (chimney) will be derived and discussed, and a parametric study on several design parameters will be performed. An analytical model based on the classic slider bearing with slip boundary will be derived and numerical models will be developed to estimate the lift force from "surfboarding", and the numerical solution will be compared with the bias of the 1FG from experiments over a range or pressures. Original contribution includes 1 ). Experimental work performed to obtain the inphase bias and quality factors in the drive and sense axes, 2). Data post-processing technique developed to obtain the structural and fluid damping of the tuning fork gyroscope, 3). Numerical simulations of the normalized Reynolds squeeze film equation and normalized Reynolds slider bearing equation on nontrivial geometry, and 4). Network model developed to solve for the pressure distribution from surfboarding with the chimney effect.