Self-alignment and navigation algorithms for DREO navigation laboratory heading reference unit.

摘要

An Attitude and Heading Reference System (AHRS), under development at the Defence Research Establishment Ottawa (DREO), consists of two, Canadian Strapdown Gyroscopes (CSG-2), and three QA1400, Q-Flex pendulous accelerometers. In this thesis, the self-alignment and strapdown navigation algorithms for the DREO AHRS are formulated.; The proposed alignment scheme is divided into two phases, namely, coarse and fine alignment. The coarse alignment stage is designed to function in a static environment and relies entirely on the inertial sensor outputs. Subsequently, an analytic fine leveling and gyrocompassing stage is used to refine the initial computation by damping any residual tilt and heading errors. Vehicle motion is not restricted during fine alignment. A damped local-level wander-azimuth mechanization is employed since it enables true worldwide navigation.; The validity of the algorithms and their software implementation is verified using simulated and real data.