Abstract:

In a platform inertial navigation system, damping network is applied to damp the gyro’s drift. For strap down inertial attitude and heading reference system (SIAHRS), gyro’s drift error can also be suppressed by the information from accelerometers. This paper proposes the idea of calculating vehicle attitude by both gyros and accelerometers, and designs a damping Kalman filter to integrate this information. However, only when the vehicle was moving without acceleration can one use the output of accelerometers to calculate its attitude. For this reason, the residual chi square test is employed in the Kalman filter to detect vehicle movement in real time. Besides, effects of outliers from measuring sensors are also considered in order to enhance system’s fault tolerant ability and sensitivity. Results of static and dynamic experiments are carried out.

Key words: SIAHRS, damp, outlier, Kalman filter, fault detection, residual