Industrial-Grade MEMS IMU Calibration

Abstract

The paper is devoted to the development of the calibration method for MEMS-sensors based inertial measurement unit (IMU). The general purpose of this work was to create the industrial-grade MEMS IMU calibration method. The method was supposed to reduce the temperature instability of inertial sensors static signal to a level of 100 °/h for rate sensors and 1 mg of accelerometers. The article provides a general description of the error types and accuracy classes of inertial sensors. The inertial sensors calibration principle using a known inertial impact series and the obtained dependence approximation by the n-th power polynomial is described too. The calibration methods for single axis and triaxial accelerometers and rate sensors using low and high precision stands are considered. Based on the considered materials, the digital inertial sensors calibration method using a triaxial high precision stand was developed. The method includes the ARS calibration over the entire measurement range and accelerometers calibration within the ±1 g range. The inertial module calibration experiment showed that the developed method allows achieving the required output signal stability level of the calibrated product over the temperature range.