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All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Lunar Surface Cargo Offloading Concepts

A sustainable presence on the lunar surface will serve as a vital training ground and technology demonstration test site in preparation for future human missions to Mars. Robotic lunar surface campaigns will focus on the exploration of resources providing information on the availability and extraction of usable resources, such as oxygen and water, and prepare the surface for a sustained human presence. Landers, outfitted with sensor packages, will be used to conduct risk-reduction activities and aid in the development of technologies prior to the crewed lunar missions that drive the need to for a logistics supply chain that requires offloading. A series of landers will be required on other planetary surfaces to build up the capabilities, capitalizing on those resources, required for sustained human presence. In each of those landers will be cargo including ascent vehicles, habitats, supplies, science packages, spare parts, fluids commodities for fuel and life support, and others varying in volume and ranging from mass in hundreds of kilograms to an estimated 6-14 metric tons to support Human Landing Systems and surface logistics requirements. This paper will examine the challenge of offloading examples of these cargo elements from different categories of landers on the lunar surface using a variety of methodologies. Challenges on the lunar surface arise with the conditions present (thermal, lighting, communications, regolith consistency), the desire to minimize mass of all landed systems, the desire to perform much of the activities with limited to minimal human interaction, and the overall configuration of the landers that are responsible for landing the cargo.

Lunar↗
NASA NTRS2018

Semi-Autonomous Rodent Habitat for Deep Space Exploration

NASA has flown animals to space as part of trailblazing missions and to understand the biological responses to spaceflight. Mice traveled in the Lunar Module with the Apollo 17 astronauts and now mice are frequent research subjects in LEO on the ISS. The ISS rodent missions have focused on unravelling biological mechanisms, better understanding risks to astronaut health, and testing candidate countermeasures. A critical barrier for longer-duration animal missions is the need for humans-in-the-loop to perform animal husbandry and perform routine tasks during a mission. Using autonomous or telerobotic systems to alleviate some of these tasks would enable longer-duration missions to be performed at the Deep Space Gateway. Rodent missions performed using the Gateway as a platform could address a number of critical risks identified by the Human Research Program (HRP), as well as Space Biology Program questions identified by NRC Decadal Survey on Biological and Physical Sciences in Space, (2011). HRP risk areas of potentially greatest relevance that the Gateway rodent missions can address include those related to visual impairment (VIIP) and radiation risks to central nervous system, cardiovascular disease, as well as countermeasure testing. Space Biology focus areas addressed by the Gateway rodent missions include mechanisms and combinatorial effects of microgravity and radiation. The objectives of the work proposed here are to 1) develop capability for semi-autonomous rodent research in cis-lunar orbit, 2) conduct key experiments for testing countermeasures against low gravity and space radiation. The hardware and operations system developed will enable experiments at least one month in duration, which potentially could be extended to one year in duration. To gain novel insights into the health risks to crew of deep space travel (i.e., exposure to space radiation), results obtained from Gateway flight rodents can be compared to ground control groups and separate groups of mice exposed to simulated Galactic Cosmic Radiation (at the NASA Space Radiation Lab). Results can then be compared to identical experiments conducted on the ISS. Together results from Gateway, ground-based, and ISS rodent experiments will provide novel insight into the effects of space radiation.

deep space gateway↗
DOE OSTI2025

Neural correspondence to spectrum of environmental uncertainty in multiple-cue probability judgment system with time delay

Despite state-of-the-art technologies like artificial intelligence, human judgment is critically essential in cooperative systems, such as the multi-agent system (MAS), which collect information among agents based on multiple-cue judgment. Human agents can prevent impaired situational awareness of automated agents by confirming situations under environmental uncertainty. System error caused by uncertainty can result in an unreliable system environment, and this environment affects the human agent, resulting in non-optimal decision-making in MAS. Thus, it is necessary to know how human behavior is changed to capture system reliability under uncertainty. Another issue affecting MAS is time delay, which can delay agent information transfer, resulting in low performance and instability. However, it is difficult to find studies on the influence of time delay on human agents. This study is about understanding the human decision-making process under a specific system reliability environment by uncertainty with time delay. We used concepts of expected and unexpected uncertainty to implement reliability of the system usage environment with three types of time delay conditions: no time delay, regular time delay, and irregular time delay conditions. We used electroencephalogram (EEG) for human cognitive neural mechanisms in multiple-cue judgment systems to understand human decision-making. In the reliability of system usage environment, the unreliable system environment significantly creates less memory load by less utilization of system rules for decision-making. In terms of time delay, delayed information delivery does not significantly affect memory load for decision-making.

cognitive process↗
NASA NTRS1962

BIOASTRONAUTICS

Bioastronautics - space environment, human performance

PHYSIOLOGY↗
NASA NTRS2005

Thermal Protection Materials Technology for NASA's Exploration Systems Mission Directorate

To fulfill the President s Vision for Space Exploration - successful human and robotic missions between the Earth and other solar system bodies in order to explore their atmospheres and surfaces - NASA must reduce trip time, cost, and vehicle weight so that payload and scientific experiment capabilities are maximized. As a collaboration among NASA Centers, this project will generate products that will enable greater fidelity in mission/vehicle design trade studies, support risk reduction for material selections, assist in optimization of vehicle weights, and provide the material and process templates for development of human-rated qualification and certification Thermal Protection System (TPS) plans. Missions performing aerocapture, aerobraking, or direct aeroentry rely on technologies that reduce vehicle weight by minimizing the need for propellant. These missions use the destination planet s atmosphere to slow the spacecraft. Such mission profiles induce heating environments on the spacecraft that demand thermal protection heatshields. This program offers NASA essential advanced thermal management technologies needed to develop new lightweight nonmetallic TPS materials for critical thermal protection heatshields for future spacecraft. Discussion of this new program (a December 2004 new start) will include both initial progress made and a presentation of the work to be preformed over the four-year life of the program. Additionally, the relevant missions and environments expected for Exploration Systems vehicles will be presented, along with discussion of the candidate materials to be considered and of the types of testing to be performed (material property tests, space environmental effects tests, and Earth and Mars gases arc jet tests).

Valentine, Peter G.↗
NASA NTRS2016

CO2 on the International Space Station: An Operations Update

PROBLEM STATEMENT: We describe CO2 symptoms that have been reported recently by crewmembers on the International Space Station and our continuing efforts to control CO2 to lower levels than historically accepted. BACKGROUND: Throughout the International Space Station (ISS) program, anecdotal reports have suggested that crewmembers develop CO2-related symptoms at lower CO2 levels than would be expected terrestrially. Since 2010, operational limits have controlled the 24-hour average CO2 to 4.0 mm Hg, or below as driven by crew symptomatology. In recent years, largely due to increasing awareness by crew and ground team, there have been increased reports of crew symptoms. The aim of this presentation is to discuss recent observations and operational impacts to lower CO2 levels on the ISS. CASE PRESENTATION: Crewmembers are routinely asked about CO2 symptoms in their weekly private medical conferences with their crew surgeons. In recent ISS expeditions, crewmembers have noted symptoms attributable to CO2 starting at 2.3 mmHg. Between 2.3 - 2.7 mm Hg, fatigue and full-headedness have been reported. Between 2.7 - 3.0 mm Hg, there have been self-reports of procedure missed steps or procedures going long. Above 3.0 - 3.4 mm Hg, headaches have been reported. A wide range of inter- and intra-individual variability in sensitivity to CO2 have been noted. OPERATIONAL / CLINICAL RELEVANCE: These preliminary data provide semi-quantitative ranges that have been used to inform a new operational limit of 3.0 mmHg as a compromise between systems capabilities and the recognition that there are human health and performance impacts at recent ISS CO2 levels. Current evidence would suggest that an operational limit between 0.5 and 2.0 mm Hg may maintain health and performance. Future work is needed to establish long-term ISS and future vehicle operational limits.

Law, Jennifer↗
NASA NTRS2016

Water Phase Change Heat Exchanger System Level Analysis for Low Lunar Orbit

In low Lunar orbit (LLO) the thermal environment is cyclic - extremely cold in the eclipse and as warm as room temperature near the subsolar point. Phase change material heat exchangers (PCHXs) are the best option for long term missions in these environments. The Orion spacecraft will use a n-pentadecane wax PCHX for its envisioned mission to LLO. Using water as a PCM material is attractive because its higher heat of fusion and greater density result in a lighter, more compact PCHX. To assess the use of a water PCHX for a human spacecraft in a circular LLO, a system level analysis was performed for the Orion spacecraft. Three cases were evaluated: 1) A one-to-one replacement of the wax PCHX on the internal thermal control loop with a water PCHX (including the appropriate control modifications), 2) reducing the radiator return setpoint temperature below Orion's value to enhance PCHX freezing, and 3) placing the water PCM on the external loop. The model showed that the water PCHX could not be used as a drop-in replacement for the wax PCHX. It did not freeze fully during the eclipse owing to its low freezing point. To obtain equivalent performance, 40% more radiator area than the Orion baseline was required. The study shows that, although water PCHXs are attractive at a component level, system level effects mean that they are not the best choice for LLO.

Navarro, Moses↗
NASA NTRSDate not supplied

Examining the Relationship between Self-Reported Workload and Resilient Performance in Airline Flight Crews

Workload has long been associated with human performance in aviation. High workload is typically viewed as a system design problem. The aim of this work was to find observable behaviors that guard cognitive resource margins; thus, improve handling of perturbations that arise. Twelve commercial airline flight crews participated in an experiment at NASA Langley Research Center. We explored workload data (NASA Task Load Index) self-reported after completing flight simulation scenarios to see how different individuals, using the same technologies, cope with challenging situations. A trained observer from the same airline as the study participants assessed performance. We differentiated a lower workload crew from a higher workload crew and analyzed their workload and performance. Results indicate that the workload may be a component of pilots’ resilient performance. Initial strategies that reduced workload were classified and these types of behaviors, if implemented correctly, might assist pilots in maintaining functional workload resource margins.

Michael Stewart↗
NASA NTRSDate not supplied

Examining the Relationship Between Workload and Resilient Performance in Airline Flight Crews

Workload has long been associated with human performance in aviation. High workload is typically viewed as a system design problem. The aim of this work was to find observable behaviors that guard cognitive resource margins; thus, improve handling of perturbations that arise. Twelve commercial airline flight crews participated in an experiment at NASA Langley Research Center. We explored workload data (NASA Task Load Index) self-reported after completing flight simulation scenarios to see how different individuals, using the same technologies, cope with challenging situations. A trained observer from the same airline as the study participants assessed performance. We differentiated a lower workload crew from a higher workload crew and analyzed their workload and performance. Results indicate that the workload may be a component of pilots’ resilient performance. Initial strategies that reduced workload were classified and these types of behaviors, if implemented correctly, might assist pilots in maintaining functional workload resource margins.

Michael Stewart↗
NASA NTRSDate not supplied

Long Term Human Presence in Space Requires Artificial Gravity and Radiation Shielding

Astronauts who spend many months in microgravity suffer serious health problems including muscle atrophy, cardiovascular deconditioning, bone calcium loss, impaired vision, and immune system changes. Exercise countermeasures have been insufficient to maintain normal human performance. Similar problems can be expected in the partial gravity of the Moon and Mars. Achieving the long-term presence of healthy humans in space requires providing artificial Earth level gravity. This can be done on the Moon and Mars by using horizontally rotating habitats with angled floors, but it is easier in space habitats. Astronauts travelling beyond the protection of the Earth’s magnetic field can suffer harm from cosmic background radiation and occasional strong solar flares. Supporting healthy long-term human lives will require radiation shielding on the Moon and Mars as well as in space. Human space settlement will probably begin with artificial rotating space habitats in Low Earth Orbit (LEO) where they will be shielded from radiation. The earlier anticipated human communities in pressurized domes on the Moon or Mars appear unrealistic because of the now known problems of partial gravity and radiation.

Astronauts↗
NASA NTRS2023

Long Term Human Presence in Space Requires Artificial Gravity and Radiation Shielding

Astronauts who spend many months in microgravity suffer serious health problems including muscle atrophy, cardiovascular deconditioning, bone calcium loss, impaired vision, and immune system changes. Exercise countermeasures have been insufficient to maintain normal human performance. Similar problems can be expected in the partial gravity of the Moon and Mars. Achieving the long-term presence of healthy humans in space requires providing artificial Earth level gravity. This can be done on the Moon and Mars by using horizontally rotating habitats with angled floors, but it is easier in space habitats. Astronauts travelling beyond the protection of the Earth’s magnetic field can suffer harm from cosmic background radiation and occasional strong solar flares. Supporting healthy long-term human lives will require radiation shielding on the Moon and Mars as well as in space. Human space settlement will probably begin with artificial rotating space habitats in Low Earth Orbit (LEO) where they will be shielded from radiation. The earlier anticipated human communities in pressurized domes on the Moon or Mars appear unrealistic because of the now known problems of partial gravity and radiation.

Astronauts↗
NASA NTRS1989

Crucial factor: human. Safely extending the human presence in space

The concept of advanced manned space missions has captured the interest and imagination of spacefaring nations. However, the physiological and psychological effects of space flight increase in magnitude and significance in the 'extended time-in-space' context. The unencumbered weightless condition enjoyed during short flights might compromise crew productivity upon return to a gravity field and extremely effective countermeasures may be essential. Missions remote from Earth require careful consideration of the medical facilities, psychological support and life support needed. The author discusses pressing issues that must be resolved before the visions of bolder human missions can be realistically fulfilled.

NASA Discipline General Space Life Sciences↗
NASA NTRS2013

Automated, Ultra-Sterile Solid Sample Handling and Analysis on a Chip

There are no existing ultra-sterile lab-on-a-chip systems that can accept solid samples and perform complete chemical analyses without human intervention. The proposed solution is to demonstrate completely automated lab-on-a-chip manipulation of powdered solid samples, followed by on-chip liquid extraction and chemical analysis. This technology utilizes a newly invented glass micro-device for solid manipulation, which mates with existing lab-on-a-chip instrumentation. Devices are fabricated in a Class 10 cleanroom at the JPL MicroDevices Lab, and are plasma-cleaned before and after assembly. Solid samples enter the device through a drilled hole in the top. Existing micro-pumping technology is used to transfer milligrams of powdered sample into an extraction chamber where it is mixed with liquids to extract organic material. Subsequent chemical analysis is performed using portable microchip capillary electrophoresis systems (CE). These instruments have been used for ultra-highly sensitive (parts-per-trillion, pptr) analysis of organic compounds including amines, amino acids, aldehydes, ketones, carboxylic acids, and thiols. Fully autonomous amino acid analyses in liquids were demonstrated; however, to date there have been no reports of completely automated analysis of solid samples on chip. This approach utilizes an existing portable instrument that houses optics, high-voltage power supplies, and solenoids for fully autonomous microfluidic sample processing and CE analysis with laser-induced fluorescence (LIF) detection. Furthermore, the entire system can be sterilized and placed in a cleanroom environment for analyzing samples returned from extraterrestrial targets, if desired. This is an entirely new capability never demonstrated before. The ability to manipulate solid samples, coupled with lab-on-a-chip analysis technology, will enable ultraclean and ultrasensitive end-to-end analysis of samples that is orders of magnitude more sensitive than the ppb goal given in the Science Instruments.

Mora, Maria F.↗
NASA NTRS1981

Functional structure and dynamics of the human nervous system

The status of an effort to define the directions needed to take in extending pilot models is reported. These models are needed to perform closed-loop (man-in-the-loop) feedback flight control system designs and to develop cockpit display requirements. The approach taken is to develop a hypothetical working model of the human nervous system by reviewing the current literature in neurology and psychology and to develop a computer model of this hypothetical working model.

Lawrence, J. A.↗