0g Climbing - The Challenge of Walking in Space

Space walking is poorly named, as it has little in common with how animals walk on Earth. Space walking is more akin to mountain climbing in scuba gear, while parachuting in a freefall-an odd combination of effects and equipment to help people do a demanding job. Robots are now being studied for service in this same domain, working on large scale space structures like the Space Station, servicing science or military platforms in high orbit, or riding on the outside of a space craft in transit to Mars, the Moon or other destinations. What have we learned about climbing in 0g? How should machines be controlled for serving in this role? What can they do to overcome the problems that humans have faced? In order to move about in this environment, a robot must be able to climb autonomously, using gaits that smoothly manage its momentum and that minimize contact forces (walking lightly) while providing for safety in the event of an emergency requiring the system to stop. All three of these objectives are now being explored at NASA's Johnson Space Center, using the Robonaut system and a set of mockups that emulate the 0g condition. NASA's goal for Robonaut is to develop the control technology that will allow it to climb on the outside of the Space Shuttle, the Space Station, and satellite mockups at JSC, enabling the robot to perform EVA task setups or serve as an Astronaut's assistant

Centaur: NASA’s mobile humanoid designed for filed work

Abstract -NASA's future lunar and martian missions will require a suite of advanced robotic systems to complete tasks during precursor visits and to assist humans while present on the surface. The Centaur is a new mobile, dexterous manipulation system designed with this future role in mind. Centaur combines the sophisticated upper body dexterity of NASA's humanoid, Robonaut, with a rugged and versatile four-wheeled base. This combination allows for robotic use of human tools and interfaces in remote locations by incorporating design improvements to the existing Robonaut that target the challenges of planetary field work: rough terrain, a varied environment (temperature, dust, wind, etc.), and distance from human operators. An overview of Centaur's design is presented focusing on the features that serve to mitigate the above risks and allow the robot to perform human-like tasks in unstructured environments. The success of this design is also demonstrated by the results of a recent coordinated field demonstration in which Centaur, under both teleoperated and autonomous control, cooperated with other NASA robots