Low Cost, High Performance GPS/IMU Attitude and Orientation System

The objective is to show that the performance requirements and costs of GPS/IMU implementations of attitude and sightline systems are substantially lower than those of conventional non- GPS aided designs. The errors of integrated GPS/IMU attitude and sightline stabilization systems are determined by simulations of these systems using complete mathematical models of IMUs and GPS receivers. The GPS and IMU models represent the full range of sensor performance plateaus available today. Dynamic motion profiles for aircraft, ships and land vehicles are generated with a 6 degree-of-freedom trajectory generator. Included is a 54 state Kalman filter with time varying dynamics and observation matrices for estimating IMU and GPS errors. The simulator outputs include differences between the navigation system solution using the simulated IMU inputs and the true trajectory results from the trajectory generator. Additional outputs are error estimates and RMS values from the Kalman filter. The sensor performance requirements and costs of integrated GPS/IMU systems are compared to those of implementations without GPS aiding. Summary plots are given that give a very unique and easy method to select the lowest cost IMU and GPS receiver that will meet a desired attitude and sightline system performance requirement.