An improved scale factor calibration model of MEMS gyroscopes

Scale factor nonlinearity is one of the main errors of MEMS gyroscopes. This paper firstly analyzes the operating principle of MEMS gyroscopes, and presents the commonly used model in calibration process. It is proved that calibrating the gyroscope scale factor in segments will result in higher fitting accuracy. Since it is difficult to determine the inverse function of a higher order function in microprocessor, this paper has developed a new calibration model, including the selection of suitable segment points based on the fitting residual error. The calibration experiments and validation test results have confirmed the high accuracy of this new model, with the calibration accuracy almost improved by one order of magnitude compared with the original model. It is also applicable to other MEMS gyroscopes.