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Throughout the manned-space programs of the National Aeronautics and Space Administration (NASA), significant data has been gathered regarding how humans live and work in the environment encountered in space. Recording operational experience helps avoid duplication of errors, can improve the design of equipment and procedures, and can provide valuable insight into human-machine and human-environment interfaces. Several sources contain valuable information about living and working in space, but are in an uncoordinated paper format. A relational database, called the Operational Experience Database, has been constructed to electronically store and organize human factors information from the Skylab and Space Shuttle missions. The taxonomy used to organize this database builds on the one used for the Skylab human-machine experiments. This information can be used by NASA engineers and operations personnel to remedy design problems, or expand on design successes.

ASDA was developed to evaluate the heat and mass transfer characteristics of advanced pressurized suit design concepts for use in low pressure or vacuum planetary environments. The model incorporates a generalized 3-layer suit, constructed with the Systems Integrated Numerical Differencing Analyzer '85 (SINDA '85), with a 41- node FORTRAN routine that simulates the transient heat transfer and respiratory processes of a human body in a suited environment. User options for the suit include a liquid cooled garment, a removable jacket, a CO2/H2O permeable layer and a phase change layer. The model also has an option to isolate flowing oxygen in the helmet from stagnant or flowing gas in the torso and limbs. Options for the environment include free and forced convection with a user input atmosphere, incident solar/infrared fluxes, radiation to a background sink and radiation and conduction to a surface. Results from a study of Mars suit concepts will also be presented.

This paper documents the Space Station Freedom (SSF) Active Thermal Control System (ATCS) performance during approach/departure, berthing, and deberthing operations. Recommended fixed radiator orientations and radiator orientations as a function of the (β angle were used for SSF flights MB5 through UF-1. Radiator rotation restrictions impacting ATCS performance included plume loads during proximity operations, minimum clearances from the Shuttle post-mating, visual cues required for mating and/or SSF remote manipulator system, attitude perturbations, number of Orbital Replacement Units (ORUs) deployed and thermal radiator rotation joint bending moment response. Three thermal models (TEA, ALPHA and TAURUS) performed the analyses on the MB5 through UF-1 mission builds. The study was divided into three parts pertaining to approach/departure, berthing, and deberthing.

AiResearch has demonstrated a high-speed axial fan that can be used for space extravehicular activity (EVA) suit ventilation. The fan provides variable flow for the suit in a lightweight, compact design. It combines fine-scale aerodynamics with air bearings and a two-pole toothless permanent magnet motor. The fan has demonstrated quiet, vibration-free operation satisfying performance requirements in a small package: 0.31 l (18.9 cu in.) in volume, 7.8 cm (7 in.) in length, with a weight under 0.9 kg (1.98 lb). This paper describes the fan and control design and discusses test results. The fan accommodates desired changes in the ventilation flow rate by allowing the astronaut to vary fan speed, achieving over a two-to-one range in flow rate. The development program tested the fan at flow rates ranging from 99 to 225 l/min (3.5 to 8 acfm) at operating pressures from 0.414 to 1.586 bar (6.0 to 23 psia) with pressure rises of 0.5 to 2.49 kPa (2.0 to 10 in. H2O).

This study assessed Active Thermal Control System Central Thermal Bus radiator rotation profiles for the Space Station Freedom in Local Vertical/Local Horizontal, two Torque Equilibrium Attitudes (MB11 and MB17), Arrow and Gravity Gradient modes while maintaining radiator angular velocities and accelerations under 45 degree/minute and 0.01 degree/sec2, respectively. To determine the thermal influence of the Flex Hose Coupler (FHC), cases ran with the ±105° radiator orientation restriction as imposed by the coupler. The study used hot thermal environments and End-Of-Life panel properties. The model used was structured to produce radiator profiles that are as close as possible to an instantaneous and local minimum environment without violating the maximum angular rotation imposed. The results from all the investigated cases indicate that the radiator should be allowed to rotate between -167° (Gravity Gradient mode) and 207° (Arrow mode).

Optimal design of spacecraft environmental control and life support systems (ECLSS) for long-duration missions requires an understanding of microgravity and its long-term influence on ECLSS performance characteristics. This understanding will require examination of the fundamental processes associated with air revitalization and water recovery in a microgravity environment. Short-term testing can be performed on NASA's reduced gravity aircraft (KC135), but longer tests will need to be conducted on the shuttle or Space Station Freedom (SSF). Conceptual designs have been prepared for ECLSS test beds that will allow extended testing of equipment under microgravity conditions. Separate designs have been formulated for air revitalization and water recovery test beds.

The Human Factors Assessment of Orbiter Missions (Detailed Supplementary Objective 904) was conducted on STS-40 (Spacelab Life Sciences 1) in order to bring human factors into the operational world of manned space flight. This paper describes some of its methods. Included are explanations of general and space human factors, and a description of DSO 904 study objectives and results. The methods described include ways to collect background information for studies and also different in-flight data collection techniques. Several lessons for the space human factors engineer are reflected in this paper. First, method development is just as important as standards generation. Second, results of investigations should always have applicability to design. Third, cooperation with other NASA groups is essential. Finally, the human is the most important component of the space exploration system, and often the most difficult to study.

The objective of this investigation was to measure and document the existence of any significant differences in physical performance under operational conditions between the Launch Entry Suit (LES) and the new Advanced Crew Escape Suit (ACES). The LES is a partial pressure suit currently worn by astronauts during the launch and entry phases of Shuttle missions. The ACES is a full pressure suit under consideration as a replacement for the LES. One prototype ACES has been fabricated and was used in this investigation. This report presents the results of three tests conducted with six subjects to allow a comparative evaluation of the two suits. The three tests included a reach envelope test, a strength test, and a treadmill test. The reach envelope test measured and compared the maximum hand displacements during horizontal and vertical reaches of both left and right arms in one-g conditions.

A thermoelectric liquid cooling system recently developed at the Johnson Space Center was evaluated in manned and unmanned ground tests as an alternative to the Space Shuttle launch and entry suit personal fan. The liquid cooling system provided superior cooling in environments simulating flight deck conditions during launch and postlanding.