Space Walking Robots - Robonaut

Space Walking Robots

Over the past five decades, space flight hardware has been designed for human servicing. Space walks are planned for most of the assembly missions for the International Space Station, and they are a key contingency for resolving on-orbit failures. Combined with substantial investment in EVA tools, this accumulation of equipment requiring a humanoid shape and an assumed level of human performance presents a unique opportunity for a humanoid system.

While the depth and breadth of human performance is beyond the current state of the art in robotics, NASA targeted the reduced dexterity and performance of a suited astronaut as Robonaut's design goals, specifically using the work envelope, ranges of motion, strength and endurance capabilities of space walking humans. This article describes the design effort for the Robonaut system.

Mechanism Design

The manipulator and dexterous hand have been developed with a substantial investment in mechatronics design. The arm structure has embedded avionics elements within each link, reducing cabling and noise contamination. Unlike some systems, Robonaut uses a chordate approach to data management, bringing all feedback to a central nervous system, where even low-level servo control is performed. This biologically inspired neurological approach is extended to left-right computational symmetry, sensor and power duality and kinematical redundancy, enabling learning and optimization in mechanical, electrical and software forms. The theory that manufacturing tools caused humans to evolve by requiring skills that could be naturally selected is applied to Robonaut's design as well. The set of EVA tools used by astronauts was the initial design consideration for the system, hence the development of Robonaut's dexterous five-fingered hand and human-scale arm that exceeds the range of motion of even unsuited astronauts. Packaging requirements for the entire system were derived from the geometry of EVA access corridors, such as pathways on the Space Station and airlocks built for humans.

NASA Is this the future of robotics...?