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Phase 2 of International Space Station (ISS) assembly is scheduled to be complete by mid 2001. This paper will describe lessons learned by the hardware providers relative to Extravehicular Activity (EVA) operation for that hardware. With the completion of flight 7A scheduled for June 2001, the space station will include the first set of US solar arrays, KU band and S band antennas, Laboratory module, Space Station Remote Manipulator System (SSRMS), and Airlock, all EVA assembled. Previously launched hardware will be reconfigured by EVA multiple times to accommodating the changing configuration of the space station to maintain operability. Since the use of EVA is critical to everything from attaching whole segments to installation of external hardware, to reconfiguration of thermal blankets, the EVA operability of this hardware has been an important aspect of the design. Many EVA operations, while well trained for, have not been previously attempted on-orbit.

Over 200 International Space Station external high maintenance items have been designed for replacement by a dexterous robotics system in addition to space-suited astronauts. Planning for dexterous robotics maintenance increases flexibility for space station operations with a robot able to execute many tasks in place of a suited crew member, lowering the number of hours crew must spend on Extravehicular Activity (EVA). The five inboard truss segments of the station - S3, S1, S0, P1 and P3 - include 122 of these robot compatible maintenance items or On-orbit Replaceable Units (ORUs). This paper describes the impact robotic compatibility has had on the International Space Station (ISS) design, reviewing the inboard truss items as examples. Diverse challenges exist to verify each genre of ORU meets the dexterous robotics requirements.

Space robotic systems, both in space and on the surface of other bodies, have distinct benefits to the accomplishment of mission objectives with lower costs and decreased risks. The demonstration of these technologies in space will also have benefits to terrestrial industries in the form of new product lines and increased competitiveness in existing fields. The purpose of this paper is to list some of these benefits and the actions that must be taken to bring them about.

This paper defines the value of free-flying cameras to the Space Station. The use of free-flying cameras is an alternative to reliance on fixed cameras. The analysis is based upon results from recent neutral buoyancy evaluations of a free-flying camera known as the Supplemental Camera and Maneuvering Platform (SCAMP). SCAMP was evaluated for inspection and viewing capabilities that will be required by Space Station. Test results demonstrated that a free-flying camera could be used effectively for inspecting structure, viewing labels, providing views for control of extravehicular robotics (EVR) and for ground assistance during extravehicular activity (EVA) tasks.

Human factors will have a profound impact on aerobrake designs of future Space Transfer Vehicles to allow the vehicles to be assembled, maintained, and refurbished on orbit. Though deployable aerobrake designs are being considered, many extravehicular activity tasks will be a necessary part of assembly and refurbishment. Crew interfaces will need to be easily operated by a suited crewman during all phases of flight. While telerobotic and autonomous systems may be developed for portions of these tasks, extravehicular activity will always be required for contingency plans. This paper details some of the critical human factor issues that must be addressed in aerobrake design based on results from aerobrake neutral buoyancy test performed in October 1990 under the McDonnell Douglas Space Systems Company Independent Research and Development program. This paper examines the need for crew restraint during assembly for torque reaction, familiar frame of reference, and speed of assembly.

As the US expands its presence in space, NASA/DOD requirements to assemble, operate, and maintain facilities in the vacuum of space will grow. Space Station Freedom (SSF) studies have shown that projected requirements for extravehicular activity (EVA) are significantly greater than the capabilities presently planned. Although the SSF design is currently being restructured by NASA with the intent of relieving its requirements for EVA, the limited availability of EVA crew time is still a critical and limiting resource to future growth and expansion. This paper details approaches to advancing extravehicular capability through EVA tools such as telerobotics and free-flyers to ensure the feasibility of assembly and maintenance of large space structures. We detail these approaches through results from aerobrake and propellant tank farm neutral buoyancy testing undertaken by McDonnell Douglas Space Systems Company (MDSSC) Independent Research and Development (IRAD).

Recent telerobotic research has included the construction and testing of free-flyers with specific missions. The Manned Maneuvering Unit (MMU) was developed for short, manned excursions in space. The Orbital Maneuvering Vehicle (OMV) was developed for servicing and reboost of satellites. The Beam Assembly Teleoperator (BAT) was developed at the Massachusetts Institute of Technology(MIT) and is presently being improved upon at the University of Maryland under NASA code R for the purpose of truss assembly. The need for free-flying vehicles will increase as humans spend more time working in space, particularly in the field of space construction. Although simple translation along the Station truss can easily be accomplished using the Crew and Equipment Translation Aid (CETA) rails or the Mobile Transporter (MT), translation to the ends of solar arrays and parts of large structures being serviced or assembled is more difficult.