Precision Pointing And Inertial Line-Of-Sight Stabilization Using Fine-Steering Mirrors, Star Trackers, And Accelerometers

Many precision pointing systems for the coming decade will require subarcsecond stability in the presence of base motion. Satellite vibration data from various sources indicates that there is base motion between 30 and 150 urad in the frequency range from 1 to 300 Hz on most vehicles, and that there may be significant motion near 1000 Hz. In many applications, optical tracking sensor data is not available with sufficient band-width to allow rejection of base motion. Such line-of-sight (LOS) stabilization systems, therefore, require inertial sensors with signal noise levels in the submicroradian range and signal bandwidths of several hundred hertz. This paper discusses inertial LOS stabilization concepts having the potential for this accuracy. We present a configuration that illustrates the performance achievable using highly linear fine-steering mirrors (FSM), star trackers with high and long-term accuracy, and accelerometers with bandwidths approaching 1000 Hz. Simulation results are included for performance prediction.