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The Desert Research and Technology Studies 2007 testing events included three test scenarios which were each tested using extravehicular activity (EVA), autonomous rover and teleoperated rover modes of operation. Task time efficiency data was collected for each mode for comparison. The site survey scenarios consisted of rover travel through a grid of Global Positioning System waypoints with data collection occurring at each waypoint. The total elapsed time for each waypoint was, on average, smallest for the autonomous mode and comparable for the EVA and teleoperated modes. The solar power unit cable deploy scenario task times were comparable between all three modes.

EVA timeline development occurs using task execution data generated through underwater training and simulation. This project collected task time data during final training events for several Space Shuttle and International Space Station missions and compared like task time data collected during on-orbit execution. Analysis was performed to compare types of activities and times required for each looking specifically for how activities can be accurately trained from a timeline planning perspective. The data revealed two significant aspects of flight timeline planning; Zero-g task times will match training times for activities that can be accurately simulated with appropriate fidelity hardware; and not all activities can be simulated sufficiently to produce training task times that will reflect required zero-g times. An approach for timeline planning utilizing this knowledge is also presented.

A new Extravehicular Activity (EVA) support equipment system was developed during the 1990’s for the International Space Station (ISS) to accommodate external maintenance. This was done in accordance with the definition of ISS as a pre-integrated truss and pressurized module architecture with externally located system components. An overview of the history of the development of this system is provided here. Definition of how this system is to be used now and in the future to maintain ISS is referred to generically as the Concept of Operations, or ConOps. A historical perspective of the ISS EVA maintenance ConOps is provided. The support equipment system and ConOps are continually evolving as ISS assembly and maintenance proceeds and the face and future of ISS is altered by changing realities within the National Aeronautics and Space Administration (NASA). A summary of how the support equipment system and ConOps has changed and is likely to further change is presented.

This report takes a comprehensive look at the ability to determine aptitude for Extravehicular Activity (EVA) of an Astronaut via an evaluation criterion. A detailed history of the EVA Skills Program and the ability to quantify EVA skills within the NASA community is presented as well as the explanation of how the program evolution was inevitable for ISS survival. It describes how the evaluation utilized within the Skills Program has become the EVA standard for instructing and evaluating the ability to perform an EVA. This report will identify the logical steps taken to emulate a real EVA. It will identify how these steps of performing an EVA tie into the evaluation process of the skills program. It will identify areas of concerns that need to be taken into consideration when utilizing this criterion.

Extravehicular activity (EVA) work efficiency is defined as a means to evaluate the on-orbit performance of the International Space Station (ISS) EVA support equipment system, worksite characteristics and basic layout of ISS for EVA maintenance. To facilitate a better understanding of the time and task data presented a brief explanation of the ISS EVA maintenance concept of operations and support equipment is system provided. Data from an ISS spacewalk is presented to calculate a task time distribution for that specific EVA. Analog data from two terrestrial based activities is presented to provide a comparison of different efficiencies. Conclusions are provided as to the effectiveness and efficiency of the ISS EVA task design and the future application of EVA task and tool related work efficiency parameters to the design of task related systems for exploration.

There has been an assembly complete maintenance concept of operations associated with International Space Station (ISS) since the earliest design stages. However, ISS has been and will be at an intermediate stage of completion for several more years, requiring an interim solution to conduct maintenance. The ISS Program's logistics and maintenance plan dictates which spare components are on-orbit already and the order in which new ones will launch. This information dictates what Extravehicular Activity (EVA) maintenance capabilities are expected, which then has to be reconciled with the support equipment available that enables EVA to perform those tasks safely and effectively. The interim solution described is characterized by use of those ISS EVA components and methods that have proven efficient and useful during the ISS assembly EVA's performed to date.

The International Space Station (ISS) program has performed 27 United States (U.S.) led Extravehicular Activities (EVA) from December of 1998 through October of 2001. These spacewalks encompass the initial docking and outfitting of the Unity Node 1 to the Zarya Functional Cargo Block vehicle, through the addition of seven major components to the ISS. This document is an overview of the anomalies associated with the U.S. ISS spacewalks up to the first ISS Expedition Crew U.S. EVA on February 20, 2002. The EVA Group at the Johnson Space Center (JSC) Mission Operations Directorate (MOD) is responsible for planning, training and flight controlling ISS EVAs. The EVA Group also document results for NASA management review. EVA results are presented here by dividing the various anomalies by type. Explanations and lessons learned are provided for anomalies relating to EVA tools, EVA tasks, Spacesuit and Airlock systems and ISS EVA actuated hardware.

An overview of the proposed operational methods for performing Extravehicular Activity (EVA) maintenance for the International Space Station (ISS) is provided. External maintenance of ISS will be required during assembly and will continue for at least ten years after assembly is complete. It is likely that the operational methodology for performing maintenance will evolve as more on-orbit ISS EVA experience is gained. However, an initial operational plan is necessary for timeline and tool development. Initial operational concepts outlining assumptions regarding how EVA operations will be conducted during maintenance of ISS after assembly complete are provided. These maintenance scenarios are designed to reduce overhead wherever possible in order to make the EVA operations more efficient. Also presented is a summation of orbital replacement unit (ORU) information as it pertains to the operational concept.