Error modeling and characterization of environmental effects for low cost inertial MEMS units

The accurate modeling of MEMS based inertial sensor errors is one of the most challenging tasks in the design of low cost navigation systems. Although the design process of inertial navigation systems mainly depends on the sensor model parameters, a standard procedure for error characterization has yet to be developed. In the first part of this study we present a new method of stability error modeling for MEMS based multi-IMU systems. The developed method uses correlation of low pass filtered sensor outputs to derive sensor error models. In the second part the effects of i) temperature ii) time and iii) G and vibration on MEMS units´ outputs are analyzed using a series of laboratory test results. A method compensating for the effect of temperature variation and modeling for residual compensation error is also explained. Better sensor models obtained with the methods presented in this paper will lead to more robust navigation systems with low cost MEMS units.