Study of Mounting Error Compensation Method for the System Design of Non-Gyro Inertial Measurement Unit

Non-gyro inertial measurement unit (NGIMU) uses only accelerometers replacing gyroscopes to compute the motion of a moving body. A new nine-accelerometer configuration of NGIMU is presented, with its experiment system built. In the system, the mounting error of the accelerometer installation, which seriously affects the precision of the navigation parameters estimation, cannot be avoidable. So a novel compensation algorithm for getting the correct accelerometer output is provided on the actual condition of existing the accelerometer mounting error. The algorithms uses the error function of the accelerometer output, and compensates the posture parameter in the traditional posture estimating algorithm to reduce the accelerometer mounting error. The simulation case and the experiment verification of the proposed methods for estimating the angular velocity are investigated based on the presented NGIMU configuration. The results show the feasibility of the configuration. In addition, in the angle measurement range of ±100 degree, the measurement precision can be improved for 3~4 degree.