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Landmark-based optical navigation using nanosatellite star trackers

This paper examines the feasibility of using optical navigation techniques for precision orbit determination. These techniques can provide autonomous and self-contained navigation estimates for satellites orbiting the Earth or other planets such as Mars. Using a combination of identified absolute landmarks and frame-to-frame image features we present an Extended Kalman navigation filter that estimates the satellite's position and velocity. Of particular interest to this study is the filter performance when absolute (e.g., catalog-referenced) landmarks are quite rare. In a reference Mars orbit scenario, our simulations present position errors in the order of tens of kilometers, or better even if absolute measurements are only available every 30 minutes.