Speckle velocimetry for high accuracy odometry for a Mars exploration rover

Abstract

The results of a preliminary study into speckle velocimetry for potential application on a Mars exploration rover are presented. Speckle velocimetry is a non-contact optical velocimetry technique intended to replace or supplement the current odometry information provided by wheel encoders. This initial study investigated the feasibility of forming speckle images from Mars soil analogues and investigated potential algorithms using a laboratory test system. The normalized cross-correlation approach is identified as the most promising processing method, with preliminary results suggesting an odometry error of 0.2% at speeds of up to 1 mm s−1 and that the technique should scale well to the higher velocities (∼85 mm s−1) typical of exploration rovers.