Planetary Cliff Descent Using Cooperative Robots

Abstract

Abstract. Future robotic planetary exploration will need to traverse geographically diverse and challenging terrain. Cliffs, ravines, and fissures are of great scientific interest because they may contain important data regarding past water flow and past life.Highly sloped terrain is difficult and often impossible to safely navigate using a single robot. This paper describes a control system for a team of three robots that access cliff walls at inclines up to 70• . Two robot assistants, or anchors, lower a third robot, called the rappeller, down the cliff using tethers. The anchors use actively controlled winches to first assist the rappeller in navigation about the cliff face and then retreat to safe ground. This paper describes the coordination of these three robots so they function as a team to explore the cliff face. Stability requirements for safe operation are identified and a behavior-based control scheme is presented. Behaviors are defined for the system and command fusion methods are described. Controller stability and sensitivity are examined. System performance is evaluated with simulation, a laboratory system, and testing in field environments.

Multi-robot Cooperation in Space: A Survey

“…Mumm et al [42] presented a system of 3 robots for these situations. It uses 2 anchor robots to lower a third robot (attached by tethers), called a 'rapeller', down a cliff by cooperative action.…”

TRESSA: Teamed robots for exploration and science on steep areas

“…A full discussion of the technical details of TRESSA have been reported in numerous publications ͑Pirjanian et al, 2002;Mumm et al, 2003Mumm et al, , 2004Huntsberger et al, 2003aHuntsberger et al, , 2003bSchenker et al, 2003aSchenker et al, , 2003bHuntsberger et al, 2004Huntsberger et al, , 2005Paulsen, Farritor, Huntsberger, & Aghazarian, 2005͒, and only details pertinent to the field expedition will be described here. This is followed by a discussion of the cliff driving and science acquisition algorithms.…”

“…The TRESSA ͑Teamed Robots for Exploration and Science on Steep Areas͒ system, previously cited in the literature as Cliffbot ͑Pirjanian et al, 2002;Mumm, Farritor, Huntsberger & Schenker, 2003;Mumm, Farritor, Pirjanian, Leger & Schenker, 2004͒, is designed to allow access to steep slopes that are not feasible for traditional wheeled rovers. Such steep slopes and cliffs are of significant scientific and geological interest.…”

A Multitasking Surface Exploration Rover System

“…These systems are not intended only for exploration. Numerous scenarios are being exploited covering different aspects of operation such as re-configurability [Iagnemma, 2000], cooperation [Trebi-Ollennu, 2002] [Bouloubasis, 2003] [Mumm, 2004], transportation [Bouloubasis, 2005] and sample recovery and return [Huntsberger, 1999]. Enhanced mobility is a characteristic required for all of these scenarios since the rovers need to traverse unstructured natural terrain.…”