The effect of the temperature-correlated error of inertial MEMS sensors on the integration of GPS/INS

The performance of inertial MEMS sensors – gyroscopes and accelerometers – depends heavily on the operating temperature. That is, their accuracy will degrade dramatically with rising temperature. In this paper the errors of inertial sensors as a result of varying temperature will be first modelled. The accuracies obtained with constant and varying temperatures will be compared and analysed. Then, the performance of the loosely-coupled GPS/MEMS-INS will be studied by simulations. The measurements are the differences of the GPS and INS positions. Two integration schemes are studied. In the first scheme, the error models of the inertial sensors are temperature-varying while they are temperature-invariant in the second scheme. That is, the temperature is not considered in the second scheme, even though the errors of the inertial sensors are temperature-varying. In this paper, three methods, including (1) control of the device’s working temperature, (2) modelling and compensation of the inertial sensors’ temperature-correlated errors, and (3) real-time compensation of these errors within the integration filter, are analysed and compared. The last method is the focus of this paper. Its effectiveness is investigated through simulations.