Centaur: A Mobile Dexterous Humanoid for Surface Operations

Future human and robotic planetary expeditions could benefit greatly from expanded Extra-Vehicular Activity (EVA) capabilities supporting a broad range of multiple, concurrent surface operations. Risky, expensive and complex, conventional EVAs are restricted in both duration and scope by consumables and available manpower, creating a resource management problem. A mobile, highly dexterous Extra-Vehicular Robotic (EVR) system called Centaur is proposed to cost-effectively augment human astronauts on surface excursions. The Centaur design combines a highly capable wheeled mobility platform with an anthropomorphic upper body mounted on a three degree-of-freedom waist. Able to use many ordinary handheld tools, the robot could conserve EVA hours by relieving humans of many routine inspection and maintenance chores and assisting them in more complex tasks, such as repairing other robots. As an astronaut surrogate, Centaur could take risks unacceptable to humans, respond more quickly to EVA emergencies and work much longer shifts. Though originally conceived as a system for planetary surface exploration, the Centaur concept could easily be adapted for terrestrial military applications such as de-Gig, surveillance and other hazardous duties

Field Validation of Nomad's Robotic Locomotion

During June and July of 1997, a mobile robot named Nomad traversed 223km in the Atacama Desert of southern Chile via transcontinental teleoperation. This unprecedented accomplishment is primarily attributed to Nomad’s innovative locomotion design which features four-wheel/all-wheel drive locomotion, a reconfigurable chassis, electronically coordinated steering, pivot-arm suspension, and body motion averaging. Nomad’s locomotion was configured through systematic analysis and simulations of the robot’s predicted performance in a variety of terrain negotiation scenarios. Experimental work with a single wheel apparatus was used to determine the effect of repeated traffic and tread pattern on power draw. Field tests before and during the Atacama traverse demonstrated Nomad’s substantial terrainability and autonomous navigation capabilities, and validated theoretical performance projections made during its geometric configuration. Most recently, the augmentation of the internal monitoring system with a variety of sensors has enabled a much more comprehensive characterization of Nomad’s terrain performance. Because of Nomad’s unique steering design a comparison of skid and explicit steering was performed by monitoring wheel torque and power during steady state turns. This paper summarizes the process and metrics of Nomad’s mobility configuration, and reports on experimental data gathered during locomotion testing