Mars Rover Localization Using Descent and Rover Imagery -
Result of the Field Test at Silver Lake, CA
Ron Li, Fei Ma, Fengliang Xu, Larry Matthies, Clark Olson, and Yalin Xiong
In Proceedings of the ASPRS Annual Conference (CDROM), Washington, D. C., 2000.
Rover localization in Mars exploration has been performed by using navigation data from a heading sensor, an odometer, and other sensors with an error of approximate 10% of the distance from the lander. A laser detector is also used to detect obstacles. In future MSP (Mars Surveyor Program) exploration missions the extent of the rover exploration site will extend from the MPF (Mars Pathfinder) landing site of 10x10m to an area of 10x10km. This calls for a significant enhancement of the rover localization accuracy of up to 0.1%.
This paper presents the result of an experiment of rover localization using descent and rover imagery acquired at the field test site at Silver Lake, CA, in May 1999. A set of simulated descent imagery from a helicopter has been taken with a coverage of 1km by 1km. 22 ground control points within the area have been surveyed by DGPS. Rover stereo images that are 5m, 500m and 1.5km away from the descent center (simulated lander position) were taken by the rover FIDO developed by JPL. Using the developed bundle adjustment system we are able to integrate the descent imagery and rover imagery to localize the rover with RMS of 0.14m, 0.08m and 0.34m in x, y and z direction, respectively, for a distance of up to 500m, and 0.23m, 0.21m and 0.46m within 1.5km. The objective of controlling the navigation error within 0.1% (1m for 1km) is apparently met.