Sun Sensor Navigation for Planetary Rovers: Theory and Field Testing

In this paper, we present an experimental study of sun sensing as a rover navigational aid. Algorithms are outlined to determine rover heading in an absolute reference frame. The sensor suite consists of a sun sensor, inclinometer, and clock (as well as ephemeris data). We describe a technique to determine ground-truth orientation in the field (without using a compass) and present a large number of experimental results (both in Toronto and on Devon Island) showing our ability to determine absolute rover heading to within a few degrees.