This paper develops a low-cost method to determine the vehicle attitude for vehicle-mounted satellite communication (satcom)-on-the-move (SOTM) uses a micro inertial measurement unit (MIMU) and a two-antenna global positioning system (GPS). An adaptive Euler-angle-based unscented Kalman filter (UKF) is utilized to fuse these sensors to guard against the effects induced by GPS outages and vehicle accelerations. When the two-antenna GPS can provide the vehicle yaw angle, the vehicle accelerations that introduce large errors to the accelerometer-measured gravitational acceleration can be corrected by the GPS-measured velocity and sideslip angle. When the two-antenna GPS fails to provide the yaw angle and needed information, the yaw angle is estimated only by integrating gyroscopes. The estimation of the pitch and roll angles is adaptively controlled by the vehicle acceleration detection rules. These rules make full use of the gyroscope output and the filtering results, which are more compatible with vehicle use than conventional accelerometer norm-based rule. The proposed method is verified with driving tests, suggesting that this technique is a viable candidate for low cost SOTM.
