Search Results

During the first two weeks of September 2005, the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Advanced Extravehicular Activity (AEVA) team led the field test portion of the 2005 Research and Technology Studies (RATS). The Desert RATS field test activity is the culmination of the various individual science and advanced engineering discipline areas year-long technology and operations development efforts into a coordinated field test demonstration under representative (analog) planetary surface terrain conditions. The purpose of the RATS is to drive out preliminary exploration concept of operations EVA system requirements by providing hands-on experience with simulated planetary surface exploration extravehicular activity (EVA) hardware and procedures.

The Advanced Extravehicular Activity (EVA) team of the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) led the Desert Research and Technology Study (RATS) in September 2004, at various test site locations near Flagstaff, Arizona. The Desert RATS is a two-week integrated remote field site test with team members from several NASA centers, universities, and industry partners participating. The overall objective of the RATS is to investigate and evaluate prototype advanced EVA exploration systems and technologies in order to develop well-defined requirements for the Vision for Space Exploration. This is accomplished by conducting simulated planetary surface exploration activities. Shirtsleeve subjects and subjects in pressurized space suits perform tasks such as geologic field mapping, rock sample collection and analysis, and communication infrastructure deployment.

In applications that require space-suited crewmembers to traverse rough terrain, boot fit and mobility are of critical importance to the crewmember's overall performance capabilities. Current extravehicular activity (EVA) boot designs were developed for micro-gravity applications, and as such, incorporate only minimal mobility features. Recently three advanced space suit boot designs were evaluated at the National Aeronautics and Space Administration Johnson Space Center (NASA/JSC). The three designs included: 1) a modified Space Shuttle suit (Extravehicular Mobility Unit or EMU) boot, 2) the Modified Experiment Boot designed and fabricated by RD & PE Zvezda JSC, and 3) a boot designed and fabricated by the David Clark Company. Descriptions of each configuration and rationale for each boot design are presented.

The first ever Astronaut - Rover (ASRO) Interaction Field Test was conducted successfully on February 22-27, 1999, in Silver Lake, Mojave Desert, California in a representative surface terrain. This test was a joint effort between the NASA Ames Research Center, Moffett Field, California and the NASA Johnson Space Center, Houston, Texas to investigate the interaction between humans and robotic rovers for potential future planetary surface exploration. As prototype advanced planetary surface space suit and rover technologies are being developed for human planetary surface exploration, it is desirable to better understand the interaction and potential benefits of an Extravehiclar Activity (EVA) crewmember interacting with a robotic rover. This interaction between an EVA astronaut and a robotic rover is seen as complementary and can greatly enhance the productivity and safety of surface excursions.

Advanced space suit mobility studies were successfully conducted during the period of May 2-17, 1998, under representative Lunar and Mars-like terrain conditions at remote field site locations in the Flagstaff, Arizona, area. The sites visited included Cinder Lake, a volcanic ash area that was an actual Apollo-era test site with simulated craters developed by the United States Geological Survey (USGS); SP Mountain, an area that contained a young lava field with extensive rock rubble; Grand Falls, a canyon area that contained a variety of rock outcroppings, volcanic ash, and rock rubble; and Meteor Crater, a young impact crater area that contained various slopes with loose rock rubble. The test activities were supported by a team of JSC personnel utilizing the MK III advanced space suit technology demonstrator suit and a NASA modified commercial liquid air backpack system. The suit test subject was Dr. Dean Eppler, a trained field geologist.

Future human exploration missions to the Moon and Mars as envisioned and being planned by the National Aeronautics and Space Administration (NASA) will involve extensive extravehicular activities (EVA's) on these planetary bodies. It will be necessary for crewmembers to don protective space suit assemblies in order to work and conduct scientific exploration activities in the harsh Lunar and Martian environments. Of prime concern is the requirement for providing the necessary and appropriate mobility features for a pressurized space suit while maintaining efficient levels of effort and relative comfort to the crewmembers during extensive periods of EVA's. A series of KC-135 aircraft reduced gravity flight demonstrations were conducted to evaluate general mobility performance characteristics of the Apollo, Shuttle and Mk III advanced technology model space suits in simulated Lunar (1/6 Earth) and Mars (0.37 Earth) gravity environments.

ILC Dover successfully designed and developed an advanced high pressure (8.3 psia) Spacesuit Glove for use on the space station. As an aide to fabrication of this glove, a feasibility study has been performed to use laser or photo optical, non contact scanning, CAD and CAM technologies. The current process for fabrication of spacesuit gloves starts by taking hand casts of a crewman's hands in one or more positions. The castings are subsequently measured by hand in critical areas, and a manual system of defining the glove bladder and glove restraint patterns follows. The proposed process will involve collecting dimensional data on hands using laser or photo optical scanning techniques. Key dimensions will be identified on a CAD system. Algorithms pre-programmed in the CAD system along with some CAD modeling will be used to manipulate the scanned data to define the glove bladder and glove restraint.

Manned extravehicular activity (EVA) operations will be major mission elements of planned future U.S. space operations. Whether designed for orbital operations or planetary surface exploration, the EVA system must be safe and reliable, and must provide a high degree of performance capabilities. An extravehicular mobility unit (EMU) consisting of a space suit, EVA gloves, and a portable life support system (PLSS) is central to the EVA system. A rugged, highly reliable, mobile, reusable, and easily maintained EVA suit and compact PLSS must meet the specific requirements of the intended mission. Additional requirements imposed by exposure to surface and gravitational environments are the need for lightweight, high-strength materials for fabricating EMU's to prevent astronaut fatigue and the need for dust protection measures and removal techniques to prevent contamination.

The NASA-developed space-suit configurations for Project Mercury and the Gemini Program originated from high-altitude-aircraft full-pressure-suit technology. These early suits lacked sophisticated mobility systems, since the suit served primarily as a backup system against the loss of cabin pressure and required limited pressurized intravehicular mobility functions for a return capability. Beginning with the Gemini Program, enhanced mobility systems were developed to enable crewmembers to perform useful tasks outside the spacecraft. The zero-prebreathe Hark III (ZPS Mk III) model of a higher operating pressure (57.2 kN/m2 (8.3 psi)) space-suit assembly represents a significant phase in the evolutionary development of a candidate operational space-suit system for the Space Station Program. The various design features and planned testing activities for the ZPS Mk III 57.2-kN/m2 (8.3 psi) space suit are described and identified.

During the early period of space-suit glove development, heavy reliance was placed on military high-altitude-aircraft full-pressure-suit technology. This status was typical of Project Mercury and early in the Gemini Program. Longer space flights and the advent of extravehicular (EV) operations required drastic improvements in the areas of comfort and mobility, and the incorporation of an EV-hazards protective coverlayer. The current advanced glove designs represent a series of evolutionary engineering efforts aimed at systematically improving higher operating pressure EV glove performance capabilities. The key glove performance issue becomes one of finding the proper balance between the basic protective requirements (i.e., EV environmental hazards) and the performance requirements of the functional glove assembly. Glove design complexity increases with the differential pressure between the glove and the vacuum of space and with the EV activity mobility task requirements.

This paper presents the results of a program to develop an improved high pressure (zero-pre-breathe) spacesuit utilizing the latest joint technology as well as materials and processes which are consistent with the space environment and suit production techniques. Other development objectives include: longer life, lower joint torques with increased ranges, improved reproducibility and reliability, facilitated resizing ability and increased overall performance capability when compared to the present Shuttle Orbiter Spacesuit at the higher pressures.