Very High Accuracy Attitude Determination for LOS Steering

In this paper the problem of line-of-sight sensing using a high-bandwidth Angular Rate Sensor (ARS), together with attitude sensors like a star tracker and a gyroscope is considered. Parametric models for the dynamics of the ARS have been identified, taking also into account model uncertainty due to temperature dependence and frequency-domain fitting errors. Based on such models, a fully integrated solution to the three-axis attitude and rate determination problem has been developed, both for on-line and off-line filtering. The performance of the developed algorithms has been assessed in a simulation study, based on test cases representative of a desired filter bandwidth up to 1 kHz.