COURSE DETERMINATION SYSTEM AND ANGULAR SPATIAL POSITION COMPLETED WITH THE OPPORTUNITY OF FUNCTIONING IN THE POLAR REGION

摘要

An attitude and heading reference system (AHRS) for a vehicle comprises an IMU that generates inertial measurements, a heading source that generates heading measurements, an attitude filter in communication with the IMU, and a heading filter in communication with the heading source. The attitude filter receives inertial measurements from the IMU; computes an attitude estimation comprising attitude estimates and covariances for the attitude estimates; and outputs the attitude estimation. The heading filter receives the heading measurements, when available, from the heading source; receives the attitude estimation, comprising the attitude estimates and the covariances for the attitude estimates; computes a heading estimation comprising a heading mean estimate and a heading variance; and outputs the heading estimation. The attitude estimation output from the attitude filter is independent of any availability of the heading measurements, such that the attitude estimation output is available at all earth regions during operation of the vehicle.