Developing Planetary Rover Traction Systems

摘要

Surface mobility will be a critical aspect of any robotic or manned planetary surface mission. The Lunar and Martian surfaces have a wide variety of terrain types, from wideranging plains to steep mountainous regions; from rock-infested boulder fields to soft sand. Prospecting rovers must have the ability to climb steep slopes and traverse soft, deep sand, while ISRU-specific rovers require high levels of traction to accomplish land-forming tasks. Whereas their terrestrial counterparts generally rely on rubber pneumatic tires, rubber tracks, or segmented steel tracks to provide high levels of traction in extreme terrain, environmental conditions and mass constraints preclude the use of these traction devices for space exploration applications. At Argo/ODG, alternative technologies are being developed in an effort to provide planetary rovers with high levels of traction while surviving the extreme environmental conditions. The metallic track developed by Argo/ODG shares characteristics of both the heavyduty steel segmented track and the high performance, lightweight rubber track used more commonly in the power-sports industry. In addition to traction characteristics, consideration was given to reliability, durability, failure modes, and efficiency over different terrain. Testing in soft, fine-grained sand has shown that the metallic track is able to produce high levels of traction, while more qualitative testing in rocky and steep terrain has shown the metallic tracks to be reliable and durable. For scenarios in which mass constraints are more severe, and very high traction levels are not required, a lightweight compliant metal wheel may provide a better compromise between traction, mass, and simplicity. Using some of the techniques and technologies that arose from track development, a simple, lightweight compliant wheel was designed for the Juno Rover. Prototyping and testing is scheduled for summer/fall of 2010 to characterize its performance against both the baseline rubber pneumatic tire and the metallic tracks.