Agility and Traction for a Lunar Rough Terrain Exploration Rover

So far, exploration rovers on moon and mars limited there traverses to mostly flat and “easy” surfaces. On the other hand, there is Opportunity or the Mars Exploration Rover-B (MER-B) getting stuck in a 30 cm sand-dune on April 26, 2005. It took until June 4, 2005 for the rover to reach firm ground again. However, many important areas to be explored on mars and moon will require a rover to travel through uneven terrain covered with rocks, craters, and crevices. This paper presents the results of preliminary work in designing and testing a locomotion system offering high agility and wheels for the Extreme Rough Terrain Lunar Exploration Rover (ERTLER). The goal of the ERTLER is to position itself on top of lava tubes or steep crater walls, to install a drill-rig, to drill and extract a sample from inside a closed section of a tube. The locomotion concept is based on wheels mounted on six individually articulated legs. To add further agility, the head section can be separately articulated around three axis. Similar to a scraper, ERTLER is capable to make tight turns. Having each wheel individually powered and articulated will allow it to overcome steep slopes, cross crevices or inchworm itself out of difficult situations. The paper will present the tests of the first prototype in a mock lunar surfaces consisting of lunar soil simulant, craters, and rocks. A special section will focus on the design and testing of a rough-terrain wheel.