Star tracking for planetary rovers

In this paper we consider the use of a star tracker as a navigational aid for planetary rovers. Depending on the complementary instruments available to the rover, star trackers can be used to determine topocentric orientation and possibly geocentric position as well. We present a set of closed-form solutions for several mechanizations and provide an analytical framework for instrument calibration. In field tests using a star tracker and inclinometer, the standard deviations in our estimates were routinely better than 0.02° in heading and 800 m in position.