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The next generation of pressure suits must enable large-scale planetary Extra-Vehicular Activities (EVA). Astronauts exploring the moon and Mars will be required to walk many kilometers, carry large loads, perform intricate experiments, and extract geological samples. Advanced pressure suit architectures must be developed to allow astronauts to perform these and other tasks simply and effectively. The research developed here demonstrates integration of robotics technology into pressure suit design. The concept of a robotically augmented pressure suit for planetary exploration has been developed through the use of analytical and experimental investigations. Two unique torso configurations are examined, including a Soft/Hard Upper Torso with individually adjustable bearings, as well as advances in Morphing Upper Torso research, in which an all-soft torso is analyzed as a system of interconnected parallel manipulators.

Performance of new space suit designs is typically tested quantitatively in laboratory tests, at both the component and integrated systems levels. As the suit moves into neutral buoyancy testing, it is evaluated qualitatively by experienced subjects, and used to perform tasks with known times in earlier generation suits. This paper details the equipment design and test methodology for extended space suit performance metrics which might be achieved by appropriate instrumentation during operational testing. This paper presents a candidate taxonomy of testing categories applicable to EVA systems, such as reach, mobility, workload, and so forth. In each category, useful technologies are identified which will enable the necessary measurements to be made. In the subsequent section, each of these technologies are examined for feasibility, including examples of existing technologies where available.

The hybrid elastic design is based upon an American Society for Engineering Education (ASEE) glove designed by at the Space Systems Laboratory (SSL) in 1985. This design uses an elastic restraint layer instead of convolute joints to achieve greater dexterity and mobility during EVA (extravehicular activity). Two pilot studies and a main study were conducted using the hybrid elastic glove and a 4000-series EMU (extravehicular activity unit) glove. Data on dexterity performance, joint range of motion, grip strength and perceived exertion was assessed for the EMU and hybrid elastic gloves with correlations to a barehanded condition. During this study, 30 test subjects performed multiple test sessions using a hybrid elastic glove and a 4000-series shuttle glove in a 4.3psid pressure environment. Test results to date indicate that the hybrid elastic glove performance is approximately similar to the performance of the 4000-series glove.

Future space missions will involve humans and robots cooperatively performing operational tasks in various team combinations. Part of the required preparation for such missions includes understanding the issues involved in task allocation between disparate agents, and efficiently ordering tasks within the mission constraints. The scheduling tool developed in this research distributes pre-allocated task primitives between a cooperative human crew and dexterous robotic team. It combines real-world precedent constraints with algorithms from scheduling theory to reorder and tighten each crew member's individual schedule. The schedules minimize astronaut involvement time by stacking astronaut-performed tasks together in the schedule. This also minimizes astronaut workload in the completion of each task. Hubble Space Telescope Servicing Mission 3A was used as an example to test the allocation and scheduling tool.

The Ranger Telerobotic Shuttle Experiment (RTSX) is a Space Shuttle-based flight experiment to demonstrate key telerobotic technologies for servicing assets in Earth orbit. The flight system will be teleoperated from onboard the Space Shuttle and from a ground control station at the NASA Johnson Space Center. The robot, along with supporting equipment and task elements, will be located in the Shuttle payload bay. A number of relevant servicing operations will be performed-including extravehicular activity (EVA) worksite setup, orbital replaceable unit (ORU) exchange, and other dexterous tasks. The program is underway toward an anticipated launch date in CY2002. This paper gives an overview of the RTSX mission, and describes several follow-on mission scenarios involving cooperative Ranger and EVA activities.

Conventional ratcheting tools do not work efficiently in confined spaces and they have other limitations when used in space during extravehicular activity (EVA). The National Aeronautics and Space Administration’s (NASA) Goddard Space Flight Center has developed a three-dimensional (3-D) sprag/roller technology that has many benefits over the ratchet mechanism. The Space Systems Laboratory at the University of Maryland is using this technology in the development of EVA tools. The research discussed here describes the testing of an EVA roller wrench aboard NASA’s Reduced-Gravity Flying Laboratory (the KC-135), evaluation by astronauts in NASA/Johnson Space Center’s Neutral Buoyancy Laboratory, and the flight of a 3-D roller mechanism on Space Shuttle Mission STS-95.