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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 217 records · Page 12

All sources NASA NTRS DOE OSTI

NASA NTRS1971

Space shuttle phase B extension, volume 2

Space shuttle systems are defined using a low technology orbiter combined with either an F-1 flyback booster or a pressure-fed booster. The mission and system requirements are given, and orbiter and booster configuration concepts are evaluated. Systems analyses and trades are discussed for LO2-RP propellent, F-1 engine main propulsion system, winged flyback recovery booster and for the pressure-fed, ocean recoverable, refurbishable booster system. Trade studies are also made for aluminum versus titanium orbiter and for crew location and compartment size.

Source record↗

NASA NTRS1985

Space Shuttle Orbiter waste collection system conceptual study

The analyses and studies conducted to develop a recommended design concept for a new fecal collection system that can be retrofited into the space shuttle vehicle to replace the existing troublesome system which has had limited success in use are summarized. The concept selected is a cartridge compactor fecal collection subsystem which utilizes an airflow collection mode combined with a mechanical compaction and vacuum drying mode that satisfies the shuttle requirements with respect to size, weight, interfaces, and crew comments. A follow-on development program is recommended which is to result in flight test hardware retrofitable on a shuttle vehicle. This permits NASA to evaluate the system which has space station applicablity before committing production funds for the shuttle fleet and space station development.

Abbate, M.↗

NASA NTRS1988

Bioisolation on the Space Station

Animal research on the Space Station presents the need for bioisolation, which is here defined as instrumental and operational provisions, which will prevent the exchange of particles greater than 0.3-micron size and microorganisms between crew and animals. Current design principles for the Biological Research Project thus call for: (1) use of specific pathogen-free animals; (2) keeping animals at all times in enclosed habitats, provided with microbial filters and a waste collection system; (3) placing habitats in a holding rack, centrifuge, and workbench, all equipped with particulate and odor filters, (4) washing dirty cage units in an equipment cleaner, with treatment and recycling of the water; (5) designing components and facilities so as to ensure maximal accessibility for cleaning; and (6) defining suitable operational procedures. Limited ground tests of prototype components indicate that proper bioisolation can thus be achieved.

Bonting, Sjoerd L.↗

NASA NTRS1992

A hybrid regenerative water recovery system for lunar/Mars life support applications

Long-duration manned space missions will require integrated biological and physicochemical processes for recovery of resources from wastes. This paper discusses a hybrid regenerative biological and physicochemical water recovery system designed and built at NASA's Crew and Thermal Systems Division at Johnson Space Center. The system is sized for a four-person crew and consists of a two-stage, aerobic, trickling filter bioreactor; a reverse osmosis system; and a photocatalytic oxidation system. The system was designed to accommodate high organic and inorganic loadings and a low hydraulic loading. The bioreactor was designed to oxidize organics to carbon dioxide and water; the reverse osmosis system reduces inorganic content to potable quality; and the photocatalytic oxidation unit removes residual organic impurities (part per million range) and provides in situ disinfection. The design and performance of the hybrid system for producing potable/hygiene water is described. Aspects of the system such as closure, automation and integration are discussed and preliminary results presented.

Verostko, Charles E.↗

NASA NTRS1991

Lunar campsite concept: Space transfer concepts and analysis for exploration missions

The lunar Campsite concept responds to a perceived need to identify early manned science and exploration missions that require minimal initial funding. The Campsite concept defers the build-up of many infrastructure components without escalating total program costs. The lunar Campsite has been sized nominally for four crew for 42 days (1 lunar night and 2 lunar days), but can be modified to span two lunar nights up to 60 days. Total mission fulfillment requires five Earth-to-LEO launches, four (100 mt class launch vehicle) for the two vehicle assemblies and one (PLS or NSTS) for the crew. The lunar Campsite mission mode is tandem direct using a booster stage and a lander stage. The booster is separated from the lander after the TLI burn and is expended into the Earth's atmosphere. In the Campsite mode, the lander lands on the surface not to be returned. In the crew delivery mode, the lander is guided to a precision landing about 500 m from the Campsite, and with enough propellant to return the crew to Earth. The Campsite consists of a habitat and airlock, body mounted radiators with a surface shield, sun tracking solar arrays, and an Earth-tracking high-gain antenna. The CV is very similar to the campsite delivery vehicle. The CV does not, however, have radiators or solar arrays. The vehicle stacks are essentially common in that they utilize the same structure system and engines, the same propellant tanks, the same 'cut-out' in which the CRV and payloads are incorporated, and the same RCS locations. The booster and lander stage propellant tank propellant capacities are identical and have margins which would allow additional fueling for propulsive capture of the boost stage into Earth orbit. This contractual study was performed to identify Campsite and vehicle interfaces and vehicle requirements, and to surface issues related to the integration of the Campsite and LTV's.

Source record↗

NASA NTRS1992

Delivery of cardiopulmonary resuscitation in the microgravity environment

The microgravity environment presents several challenges for delivering effective cardiopulmonary resuscitation (CPR). Chest compressions must be driven by muscular force rather than by the weight of the rescuer's upper torso. Airway stabilization is influenced by the neutral body posture. Rescuers will consist of crew members of varying sizes and degrees of physical deconditioning from space flight. Several methods of CPR designed to accommodate these factors were tested in the one G environment, in parabolic flight, and on a recent shuttle flight. Methods: Utilizing study participants of varying sizes, different techniques of CPR delivery were evaluated using a recording CPR manikin to assess adequacy of compressive force and frequency. Under conditions of parabolic flight, methods tested included conventional positioning of rescuer and victim, free floating 'Heimlich type' compressions, straddling the patient with active and passive restraints, and utilizing a mechanical cardiac compression assist device (CCAD). Multiple restrain systems and ventilation methods were also assessed. Results: Delivery of effective CPR was possible in all configurations tested. Reliance on muscular force alone was quickly fatiguing to the rescuer. Effectiveness of CPR was dependent on technique, adequate restraint of the rescuer and patient, and rescuer size and preference. Free floating CPR was adequate but rapidly fatiguing. The CCAD was able to provide adequate compressive force but positioning was problematic. Conclusions: Delivery of effective CPR in microgravity will be dependent on adequate resuer and patient restraint, technique, and rescuer size and preference. Free floating CPR may be employed as a stop gap method until patient restraint is available. Development of an adequate CCAD would be desirable to compensate for the effects of deconditioning.

Barratt, M. R.↗

NASA NTRS2010

Preliminary Results of Bisphosphonate ISS Flight Experiment

Bone loss has been recognized as a potential problem from the beginning of human spaceflight. With the spaceflight missions lasting 6 months to potentially 3 years or longer this issue has assumed increased significance. Detailed measurements from the Mir and ISS long duration missions have documented losses in bone mineral density (BMD) from the total skeleton and critical sub-regions. The most important losses are from the femoral hip averaging about -1.6%/mo integral to -2.3%/mo trabecular BMD. Importantly these studies have documented the wide range in individual response from -0.5 to -5%/mo in BMD. Given the small size of any expedition crew, the wide range of responses has to be considered in the implementation of any countermeasure. Assuming that it is unlikely that the susceptibility for bone loss in any given crewmember will be known, a suite of bone loss countermeasures will likely be needed to insure protection of all crewmembers. The hypothesis for this experiment is that the combined effect of anti-resorptive drugs plus the standard in-flight exercise regimen will have a measurable effect on preventing space flight induced bone loss and strength and will reduce renal stone risk. To date, 4 crewmembers have completed the flight portion of the protocol in which crewmembers take a 70-mg alendronate tablet once a week before and during flight, starting 17 days before launch. Compared to previous ISS crewmembers (n=14) not taking alendronate, DXA measurements of the total hip BMD were significantly changed from -1.1 0.5%/mo to 0.04 0.3%/mo (p<0.01); QCT-determined trabecular BMD of the total hip was significantly changed from -2.3 1.0%/mo to -0.3 1.6%/mo (p<0.01). Significance was calculated from a one-tailed t test. While these results are encouraging, the current n (4) is small, and the large SDs indicate that while the means are improved there is still high variability in individual response. Four additional crewmembers have been recruited to participate in this experiment, with expected completion of these flights by late 2011.

LeBlanc, Adrian↗

NASA NTRS2020

University of Maryland Minimum Crew Cabin Studies ENAE484 X-Hab Final Report

With renewed interest in human spaceflight, and the astronomically high cost to send things into space, NASA is looking into methods for minimizing all aspects of crewed flight. While maintaining a crew of at least two to four people, there are considerations into duration, habitat size, habitat orientation, and many other factors to try and get the most science, safely, for the least amount of money. From these constraints, the class' project was organized. The topic of "Minimum Crew Cabin Sizing" was chosen, with a plan to do experimentation to verify or update some of the volumetric models for various activities. The actual crew cabin itself is something that can easily alter the mass, cost, and development time. In trying to quantify how small is too small { or what can be made smaller { programs can save money, time, and mass with an appropriately sized minimum volume habitat.

David Lee Akin↗

NASA NTRS2016

A Proposed Ascent Abort Flight Test for the Max Launch Abort System

The NASA Engineering and Safety Center initiated the Max Launch Abort System (MLAS) Project to investigate alternate crew escape system concepts that eliminate the conventional launch escape tower by integrating the escape system into an aerodynamic fairing that fully encapsulates the crew capsule and smoothly integrates with the launch vehicle. This paper proposes an ascent abort flight test for an all-propulsive towerless escape system concept that is actively controlled and sized to accommodate the Orion Crew Module. The goal of the flight test is to demonstrate a high dynamic pressure escape and to characterize jet interaction effects during operation of the attitude control thrusters at transonic and supersonic conditions. The flight-test vehicle is delivered to the required test conditions by a booster configuration selected to meet cost, manufacturability, and operability objectives. Data return is augmented through judicious design of the boost trajectory, which is optimized to obtain data at a range of relevant points, rather than just a single flight condition. Secondary flight objectives are included after the escape to obtain aerodynamic damping data for the crew module and to perform a high-altitude contingency deployment of the drogue parachutes. Both 3- and 6-degree-of-freedom trajectory simulation results are presented that establish concept feasibility, and a Monte Carlo uncertainty assessment is performed to provide confidence that test objectives can be met.

Tartabini, Paul V.↗

NASA NTRS1992

Potential health effects of fume particles on the crew of spacecrafts

The effect of the size of polymer (e.g., Teflon) particles in fumes inhaled by spacecraft personnel on the condition of the lung tissue and on the recovery of the exposed subjects was investigated in rats receiving a single intrapulmonary instillation, or repeated inhalation exposures to either TiO2 particles with primary particle diameter 20 nm, or TiO2 particles with primary particle diameter 250 nm. It was found that rats exposed to 20-nm-diam particles showed a dramatically higher toxicity and slower recovery compared to the group exposed to the 250-nm-diam particles, due to a larger extent of penetration of the interstitium of the lung by the finer particles.

Ferin, Juraj↗

NASA NTRS2012

Benefits of a Single-Person Spacecraft for Weightless Operations

Historically, less than 20 percent of crew time related to extravehicular activity (EVA) is spent on productive external work.1 A single-person spacecraft with 90 percent efficiency provides productive new capabilities for maintaining the International Space Station (ISS), exploring asteroids, and servicing telescopes or satellites. With suits, going outside to inspect, service or repair a spacecraft is time-consuming, requiring pre-breathe time, donning a fitted space suit, and pumping down an airlock. For ISS, this is between 12.5 and 16 hours for each EVA, not including translation and work-site set up. The work is physically demanding requiring a day of rest between EVAs and often results in suit-induced trauma with frequent injury to astronauts fingers2. For maximum mobility, suits use a low pressure, pure oxygen atmosphere. This represents a fire hazard and requires pre-breathing to reduce the risk of decompression sickness (bends). With virtually no gravity, humans exploring asteroids cannot use legs for walking. The Manned Maneuvering Unit offers a propulsive alternative however it is no longer in NASA s flight inventory. FlexCraft is a single person spacecraft operating at the same cabin atmosphere as its host so there is no risk of the bends and no pre-breathing. This allows rapid, any-time access to space for repeated short or long EVAs by different astronauts. Integrated propulsion eliminates hand-over-hand translation or having another crew member operate the robotic arm. The one-size-fits-all FlexCraft interior eliminates the suit part inventory and crew time required to fit all astronauts. With a shirtsleeve cockpit, conventional displays and controls are used and because the work is not strenuous no rest days are required. Furthermore, there is no need for hand tools because manipulators are equipped with force multiplying end-effectors that can deliver the precise torque for the job.

Griffin, Brand N.↗

NASA NTRS2012

Deep Space Habitat Configurations Based On International Space Station Systems

A Deep Space Habitat (DSH) is the crew habitation module designed for long duration missions. Although humans have lived in space for many years, there has never been a habitat beyond low-Earth-orbit. As part of the Advanced Exploration Systems (AES) Habitation Project, a study was conducted to develop weightless habitat configurations using systems based on International Space Station (ISS) designs. Two mission sizes are described for a 4-crew 60-day mission, and a 4-crew 500-day mission using standard Node, Lab, and Multi-Purpose Logistics Module (MPLM) sized elements, and ISS derived habitation systems. These durations were selected to explore the lower and upper bound for the exploration missions under consideration including a range of excursions within the Earth-Moon vicinity, near earth asteroids, and Mars orbit. Current methods for sizing the mass and volume for habitats are based on mathematical models that assume the construction of a new single volume habitat. In contrast to that approach, this study explored the use of ISS designs based on existing hardware where available and construction of new hardware based on ISS designs where appropriate. Findings included a very robust design that could be reused if the DSH were assembled and based at the ISS and a transportation system were provided for its return after each mission. Mass estimates were found to be higher than mathematical models due primarily to the use of multiple ISS modules instead of one new large module, but the maturity of the designs using flight qualified systems have potential for improved cost, schedule, and risk benefits.

Smitherman, David↗

NASA NTRS2012

Deep Space Habitat Configurations Based on International Space Station Systems

Smitherman, David↗

DOE OSTI2023

Logging Crew Attributes by Region in the Southeast USA

Urbanization, shrinking markets, and reduced forestry investment may affect harvesting efficiency in regions of the US South. To monitor these conditions, logging businesses have been tracked by surveys conducted by universities and trade associations. This project used a sampling approach coordinated with FIA utilization studies to sample logging crews based on a harvesting location. The approach was used to develop relationships among firm attributes and site attributes in six southeastern states (AL, GA, FL, NC, SC, and VA) from 2011 to 2018. The data included harvest attributes (location, harvest size and stand type) and logging firm attributes (production, crew labor, crew number, the number of machines by type, and machine age). For crew capital value, an equation was developed for this study using machine number and average machine age. The data from logging crews on 419 harvests were analyzed by region, harvest size, and stand type. Mean values for crew labor ranged from 3.1 to 7.1 workers. The average capital value per crew ranged from $\$220,000$ to $\$524,000$ per crew in the Coastal Plain with a narrower range in the Piedmont. In the Coastal Plain, higher productivity was detected for larger harvests and pine versus hardwood and mixed stands; however, in the Piedmont those trends were less obvious. Ratio of feller-bunchers, skidders and loaders were mostly 1:1:1 or 1:2:1 with 41% and 24% of samples, respectively. There were notable trends among Coastal Plain loggers regarding capital value and productivity with evidence supported by a production function. The differences in Piedmont (e.g., ownership size, market access, terrain, population density, etc.) may combine to limit daily production and labor productivity.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS1963

HABITABILITY IN SPACE STATIONS

What does habitability mean? This word is commonly used and is bandied about as a thing which is necessary and desirable for all manned flight vehicles. But what does it really mean? A serious examination of the meaning of the term soon leads to attempts at definition into discussions of the interplay of such factors as the mission, the size and makeup of the crew, the jobs within the mission, the flight duration, the stress loads, the vehicle to be used, the comfort, and the deprivations inherent in the mission, the flight environment, et cetera. In other words, habitability might be considered the resultant of the interplay of all of the factors related to the man, his machine, his environment, and the mission to be accomplished. It is more easily visualized as the state of being at the completion of the interaction of all of the-factors rather than a discrete entity itself. Therefore, the provisions made to meet the habitability requirements can contribute to or be detrimental in meeting the program objectives. The requirement placed upon the space vehicle may be eased if necessary through the proper selection and training of the crewmen, The motivation of the crew may be an additional aid in providing a satisfactory solution to the habitability needs. The design and development of the space vehicle should avoid depending upon special selection and unusual training to meet the basic provisions needed to support the men in the space environment. The vehicle provisions should stand upon their own merit. Difficult and hazardous missions can he made more tolerable through augmentation of the provisions for habitability. For the sake of this discussion of habitability in a space station, this concept will be considered. This paper will emphasize a discussion of the interplay of some of these broader and little discussed factors as they reflect themselves in the development and operation of the space stations, rather than represent a list of items which have been established as essential for crew provisions. Ignoring these allied factors can lead to a successful mechanical system that will operate in space, yet a complete failure in providing the working, relaxing, and living areas so necessary for man if he is to maintain his productivity.

Space station↗

NASA NTRS1977

Carry-on Shuttle payloads, or how to 'CON' the system

The three types of life-science payload carried by the Space Shuttle are briefly discussed. These are the carry-on (CON), the minilab, and the dedicated life-science laboratory. The latter two payloads relate to experiments with animals, plants, and other biological forms. The CON payload is a package weighing up to 200 lb (up to 5 cu ft in size) which, without requiring a crew interface nor direct connection with the Shuttle, will provide such support as power, cooling, feeding, etc. The configuration and principal characteristics of each type of payload are presented.

Winter, D. L.↗

NASA NTRS1986

An improved waste collection system for space flight

Waste collection systems are a critical part of manned space flight. Systems to date have had a number of deficiencies. A new system, which uses a simple mechanical piston compactor and disposable pads allows a clean area for defecation and maximum efficiency of waste collection and storage. The concept has been extensively tested. Flight demonstration units are being built, tested, and scheduled for flight. A prototype operational unit is under construction. This system offers several advantages over existing or planned systems in the areas of crew interface and operation, cost, size, weight, and maintenance and power consumption.

Thornton, William E.↗

NASA NTRS2003

Experiences with Lab-on-a-chip Technology in Support of NASA Supported Research

Under the auspices of the Microgravity Sciences and Application Department at Marshall Space Flight Center, we have custom designed and fabricated a lab-on-a-chip (LOC) device, along with Caliper Technologies, for macromolecular crystal growth. The chip has been designed to deliver specified proportions of up-to five various constituents to one of two growth wells (on-chip) for crystal growth. To date, we have grown crystals of thaumatin, glucose isomerase and appoferitin on the chip. The LOC approach offered many advantages that rendered it highly suitable for space based hardware to perform crystal growth on the International Space Station. The same hardware that was utilized for the crystal growth investigations, has also been used by researchers at Glenn Research Center to investigate aspects of microfluidic phenomenon associated with two-phase flow. Additionally, our LOCAD (Lab-on-a-chip Application Development) team has lent its support to Johnson Space Center s Modular Assay for Solar System Exploration project. At present, the LOCAD team is working on the design and build of a unique lab-on-a-chip breadboard control unit whose function is not commercially available. The breadboard can be used as a test bed for the development of chip size labs for environmental monitoring, crew health monitoring assays, extended flight pharmacological preparations, and many more areas. This unique control unit will be configured for local use and/or remote operation, via the Internet, by other NASA centers. The lab-on-a-chip control unit is being developed with the primary goal of meeting Agency level strategic goals.

Monaco, Lisa↗