Abstract: To clarify the relation between linearity of a micro- accelerometer and the input acceleration in a centrifugal test, a cubic mathematic model is built and the least squared criterion is applied in the analysis of closed-loop system output. Linear-ity formulae are put forward and proved that the linearity is a quadric function of input, and relates to open-loop gain of low frequency band. The formulae indicate theoretical means to improve linearity by altering electrical and structural parameters. Electrometric method is used to measure mechanical parameters, and the formulae are verified by centrifugal testing data. The result shows that linearity can be estimated according to the mathematic model obtained in the static rolling test, and calcu-lated values are close to corresponding measured values.

Key words: Centrifugal experiment, Linearity, Mathematic model, Micro-accelerometer, Micro-electro-mechanical system (MEMS), Positional error