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At least 145 records · Page 8

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NASA NTRS1988

An overview of the space medicine program and development of the Health Maintenance Facility for Space Station

Because the prolonged stay on board the Space Station will increase the risk of possible inflight medical problems from that on Skylab missions, the Health Maintenance Facility (HMF) planned for the Space Station is much more sophisticated than the small clinics of the Skylab missions. The development of the HMF is directed by the consideration of three primary factors: prevention, diagnosis, and treatment of injuries and illnesses that may occur in flight. The major components of the HMF include the clinical laboratory, pharmacy, imaging system, critical-care system, patient-restraint system, data-management system, exercise system, surgical system, electrophysiologic-monitoring system, introvenous-fluid system, dental system, and hyperbaric-treatment-support system.

Pool, Sam Lee↗

NASA NTRS1989

The history of in-flight exercise in the US manned space program

A historical perspective on in-flight exercise in the U.S. manned space program is given. We have learned a great deal in the 25 years since the inception of Project Mercury. But, as we look forward to a Space Station and long-duration space flight, we must recognize the challenge that lies ahead. The importance of maintenance of the crewmember's physical condition during long stays in weightlessness is a prime concern that should not be minimized. The challenge lies in the design and development of exercise equipment and protocols that will prevent or minimize the deleterious sequelae of long-duration space flight while maximizing valuable on-orbit crew time.

Moore, Thomas P.↗

NASA NTRSDate not supplied

Conjunction Assessment(CA) Support Overview for the EOS Satellites

When a satellite is placed into its desired orbit, to achieve its designed mission objectives, it is imperative to maintain orbit requirements as well as the overall health and safety of the vehicle. One integral part of this process is ensuring that the satellite does not collide with any other vehicle or object in space, which can cause a detrimental consequence to the mission as well as to other satellites within the same orbit regime. To prevent such an occurrence, a thorough collision avoidance process must be followed. This process includes constantly monitoring potential conjunctions and performing collision avoidance maneuvers when necessary, while remaining within the limitations of the mission’s orbit maintenance requirements. This presentation will describe the Earth Observing System (EOS) Aqua, Aura and Terra satellite’s operational collision a! voidance process. It will highlight the routine conjunction assessment screening and data evaluation process performed by the NASA/GSFC EOS Collision Avoidance Engineers. The presentation will include background information, a summary of operational activities and duties, internal tools used for support, EOS High Interest Event statistics, and potential challenges expected in the future.

Syed Hasan↗

NASA NTRS2009

Thermal Insulation Strips Conserve Energy

Launching the space shuttle involves an interesting paradox: While the temperatures inside the shuttle s main engines climb higher than 6,000 F hot enough to boil iron for fuel, the engines use liquid hydrogen, the second coldest liquid on Earth after liquid helium. Maintained below 20 K (-423 F), the liquid hydrogen is contained in the shuttle s rust-colored external tank. The external tank also contains liquid oxygen (kept below a somewhat less chilly 90 K or -297 F) that combines with the hydrogen to create an explosive mixture that along with the shuttle s two, powdered aluminum-fueled solid rocket boosters allows the shuttle to escape Earth s gravity. The cryogenic temperatures of the main engines liquid fuel can cause ice, frost, or liquefied air to build up on the external tank and other parts of the numerous launch fueling systems, posing a possible debris risk when the ice breaks off during launch and causing difficulties in the transfer and control of these cryogenic liquid propellants. Keeping the fuel at the necessary ultra-cold temperatures while minimizing ice buildup and other safety hazards, as well as reducing the operational maintenance costs, has required NASA to explore innovative ways for providing superior thermal insulation systems. To address the challenge, the Agency turned to an insulating technology so effective that, even though it is mostly air, a thin sheet can prevent a blowtorch from igniting a match. Aerogels were invented in 1931 and demonstrate properties that make them the most extraordinary insulating materials known; a 1-inch-thick piece of aerogel provides the same insulation as layering 15 panes of glass with air pockets in between. Derived from silica, aluminum oxide, or carbon gels using a supercritical drying process - resulting in a composition of almost 99-percent air - aerogels are the world s lightest solid (among 15 other titles they hold in the Guinness World Records), can float indefinitely on water if treated to be hydrophobic, and can withstand extremely hot temperatures (from 1,100 F to 3,000 F depending on the type of aerogel) down to cryogenic levels, making this "frozen smoke" ideal for use in space. Because of its low weight and ability to withstand temperature extremes, an aerogel was even used as the space-based catcher s mitt to trap comet particles and space dust for NASA s Stardust mission, launched in 1999. All of this remarkable technology s characteristics were ideal for NASA s purposes except one: The aerogels were extremely brittle. Through a long-term partnership between Kennedy Space Center and Aspen Aerogels Inc., of Northborough, Massachusetts, researchers developed a flexible, durable form of aerogel that NASA has since used as cryogenic insulation for space shuttle launch systems. Through Aspen Aerogels, the technology has made oil pipeline insulation, extreme weather clothing, and infrared shielding for combat helicopters.

Source record↗

NASA NTRS2000

Role of Integrin in Mechanical Loading of Osteoblasts

Mechanical forces generated by gravity, weightbearing, and muscle contraction play a key role in the genesis and maintenance of skeletal structure. The molecular mechanisms that mediate changes in osteoblast activity in response to altered patterns of skeletal loading are not known, and a better understanding of these processes may be essential for developing effective treatment strategies to prevent disuse osteoporosis. We have elucidated specific integrin/ECM (extracellular matrix) interactions that are required for osteoblast differentiation and survival and have developed a useful loading system to further explore the molecular basis of mechano-sensitivity of osteoblasts. The long term goal of our collaborative research is to understand how the ECM and cell adhesion proteins and integrins interaction to mediate the response of osteoblasts and their progenitors to mechanical loading. We suggest that integrin/ECM interactions are crucial for basic cellular processes, including differentiation and survival, as well as to participate in detecting and mediating cellular responses to mechanical stimuli.

Globus, Ruth↗

NASA NTRSDate not supplied

Physics-Guided Deep Learning for Complex System Health Management and Decision Making

The landscape of complex engineered systems is rapidly evolving, from smart manufacturing facilities to next-generation transportation vehicles. As these systems become increasingly sophisticated and interconnected, the need for advanced health management systems grows ever more critical. These systems must go beyond simple monitoring, actively predicting potential failures before they occur. This paradigm shift from fixed maintenance schedules to condition-based predictions is key to optimizing system performance, enhancing safety, and paving the way for autonomous decision-making across various industries. Whether in industrial processes, energy systems, or advanced transportation, the ability to anticipate and prevent failures is becoming a cornerstone of operational excellence. To accurately predict the future health of any complex system, knowledge of its current health state and future operational conditions is essential. Recent advancements in data-driven algorithms have generated growing interest in artificial intelligence for industrial applications. However, the limitations of pure data-driven methods, particularly in industries where data acquisition is costly and limited, have become apparent. This has led to a focus on blending physics with data-driven algorithms, mitigating the drawbacks of both approaches while emphasizing their respective advantages. This research proposes a novel framework for integrating physics-based performance models with deep learning algorithms for the prognostics of complex safety-critical systems. In this approach, physics-based models serve as a blueprint, capturing fundamental system behaviors, while deep learning algorithms, leveraging real-world sensor data, fill in gaps and identify subtle patterns indicative of potential problems. This hybrid methodology, utilizing techniques such as Physics-Informed Neural Networks (PINNs), offers a powerful solution for predicting system health. By fusing domain knowledge with data-driven insights, this approach promises more accurate, adaptable, and reliable models for health prediction. The resulting framework is versatile, applicable across various sectors including aerospace, manufacturing, and energy systems, ultimately contributing to safer, more efficient operations in our increasingly complex technological landscape.

Diagnostics↗

NASA NTRS2014

Shuttle Flight Operations Contract Generator Maintenance Facility Land Use Control Implementation Plan (LUCIP)

This Land Use Control Implementation Plan (LUCIP) has been prepared to inform current and potential future users of the Kennedy Space Center (KSC) Shuttle Flight Operations Contract Generator Maintenance Facility (SFOC; SWMU 081; "the Site") of institutional controls that have been implemented at the Site1. Although there are no current unacceptable risks to human health or the environment associated with the SFOC, an institutional land use control (LUC) is necessary to prevent human health exposure to antimony-affected groundwater at the Site. Controls will include periodic inspection, condition certification, and agency notification.

Remediation↗

NASA NTRS2010

Using Facility Condition Assessments to Identify Actions Related to Infrastructure

To support cost effective, quality research it is essential that laboratory and testing facilities are maintained in a continuous and reliable state of availability at all times. NASA Langley Research Center (LaRC) and its maintenance contractor, Jacobs Technology, Inc. Research Operations, Maintenance, and Engineering (ROME) group, are in the process of implementing a combined Facility Condition Assessment (FCA) and Reliability Centered Maintenance (RCM) program to improve asset management and overall reliability of testing equipment in facilities such as wind tunnels. Specific areas are being identified for improvement, the deferred maintenance cost is being estimated, and priority is being assigned against facilities where conditions have been allowed to deteriorate. This assessment serves to assist in determining where to commit available funds on the Center. RCM methodologies are being reviewed and enhanced to assure that appropriate preventive, predictive, and facilities/equipment acceptance techniques are incorporated to prolong lifecycle availability and assure reliability at minimum cost. The results from the program have been favorable, better enabling LaRC to manage assets prudently.

Rubert, Kennedy F.↗

NASA NTRS2014

A Historical Analysis of Crane Mishaps at Kennedy Space Center

Cranes and hoists are widely used in many areas. Crane accidents and handling mishaps are responsible for injuries, costly equipment damage, and program delays. Most crane accidents are caused by preventable factors. Understanding these factors is critical when designing cranes and preparing lift plans. Analysis of previous accidents provides insight into current recommendations for crane safety. Cranes and hoists are used throughout Kennedy Space Center to lift everything from machine components to critical flight hardware. Unless they are trained crane operators, most NASA employees and contractors do not need to undergo specialized crane training and may not understand the safety issues surrounding the use of cranes and hoists. A single accident with a crane or hoist can injure or kill people, cause severe equipment damage, and delay or terminate a program. Handling mishaps can also have a significant impact on the program. Simple mistakes like bouncing or jarring a load, or moving the crane down when it should go up, can damage fragile flight hardware and cause major delays in processing. Hazardous commodities (high pressure gas, hypergolic propellants, and solid rocket motors) can cause life safety concerns for the workers performing the lifting operations. Most crane accidents are preventable with the correct training and understanding of potential hazards. Designing the crane with human factors taken into account can prevent many accidents. Engineers are also responsible for preparing lift plans where understanding the safety issues can prevent or mitigate potential accidents. Cranes are widely used across many areas of KSC. Failure of these cranes often leads to injury, high damage costs, and significant delays in program objectives. Following a basic set of principles and procedures during design, fabrication, testing, regular use, and maintenance can significantly minimize many of these failures. As the accident analysis shows, load drops are often caused or influenced by human factors. Therefore, proper training and understanding of crane safety throughout the workforce is critical. It is important that the engineers designing the cranes, lift planners preparing the lift plans, operators performing the lifts, and training officers conducting the operator training all understand the problems that can happen with cranes and how to ensure the safety of the workforce and equipment being lifted.

Materials Handling↗

NASA NTRS2016

Sorbent Structural Testing on Carbon Dioxide Removal Sorbents for Advanced Exploration Systems

Long term space missions require carbon dioxide removal systems that can function with minimal downtime required for maintenance, low power consumption and maximum efficiency for CO2 removal. A major component of such a system are the sorbents used for the CO2 and desiccant beds. Sorbents must not only have adequate CO2 and H2O removal properties, but they must have the mechanical strength to prevent structural breakdown due to pressure and temperature changes during operation and regeneration, as well as resistance to breakdown due to moisture in the system from cabin air. As part of the studies used to select future CO2 sorbent materials, mechanical tests are performed on various zeolite sorbents to determine mechanical performance while dry and at various humidified states. Tests include single pellet crush, bulk crush and attrition tests. We have established a protocol for testing sorbents under dry and humid conditions, and previously tested the sorbents used on the International Space Station carbon dioxide removal assembly. This paper reports on the testing of a series of commercial sorbents considered as candidates for use on future exploration missions.

Watson, David↗

NASA NTRS2006

Emerging technologies for V&V of ISHM software for space exploration

Systems1,2 required to exhibit high operational reliability often rely on some form of fault protection to recognize and respond to faults, preventing faults' escalation to catastrophic failures. Integrated System Health Management (ISHM) extends the functionality of fault protection to both scale to more complex systems (and systems of systems), and to maintain capability rather than just avert catastrophe. Forms of ISHM have been utilized to good effect in the maintenance phase of systems' total lifecycles (often referred to as 'condition-based mainte-nance'), but less so in a 'fault protection' role during actual operations. One of the impediments to such use lies in the challenges of verification, validation and certification of ISHM systems themselves. This paper makes the case that state-of-the-practice V&V and certification techniques will not suffice for emerging forms of ISHM systems; however, a number of maturing software engineering assurance technologies show particular promise for addressing these ISHM V&V challenges.

fault detection, isolation, and recovery↗

NASA NTRS2009

QuEST: Qualifying Environmentally Sustainable Technologies

In 2004, in one of their first collaborative efforts, Centro Para Prevencao da Poluicao (Portuguese Center for Pollution Prevention or C3P). teamed with Technology Evaluation for Environmental Risk Mitigation Principal Center (TEERM) and two Portuguese entities, TAP Portugal (Portuguese National Airline) and OGMA Indtistria Aeron utica de Portugal (Portuguese Aeronautics Industry), to target the reduction of hexavalent chromium, cadmium, and volatile organic compounds (VOCs) in aircraft maintenance operations. This project focused on two coating systems that utilize non-chrome pretreatments and low-VOC primers and topcoats.

Lewis, Pattie L.↗

NASA NTRS1992

Medicine on Mars: Remote medical care and the space exploration initiative

Mars exploration missions as described in the Synthesis Group report will involve extended exposures of crew members to remote, hazardous environments for up to 100 days. Maintenance of crew health and performance will be critical to ensure mission success. Because of the great distances between the Earth and Mars, round trip telecommunication will take from seven to forty minutes and immediate return to Earth will not be feasible: an autonomous medical care system that integrates preventive, occupational, and environmental aspects of health care and provides diagnostic and treatment capabilities will be necessary. Providing medical care for Mars explorers will pose some unique technical and engineering challenges. Medical care equipment will need to be designed to be modular and portable to ensure that it is interchangeable between vehicle and planetary surface elements. Miniaturization will be necessary to reduce mass and volume. Computerized systems that automatically acquire and manage medical information and provide medical references (literature), decision support, and automated medical record keeping will be a crucial part of a Martian medical care system. Medical care will also rely on remote consultation with Earth-based specialists. This presentation will provide an overview of the health and medical concerns associated with Mars exploration missions and will describe some specific concepts for Mars medical care systems.

Simmons, S. C.↗

NASA NTRS1977

Some physiological effects of alternation between zero gravity and one gravity

The anatomy and physiology of the healthy vestibular system and the history of its study, maintenance of muskuloskeletal fitness under low-gravity conditions, tests of motion sickness, and data and techniques on testing subjects in a slow rotation room, are covered. Components of the inner ear labyrinth and their behavior in relation to equilibrium, gravity and inertial forces, motion sickness, and dizziness are discussed. Preventive medicine, the biologically effective force environment, weightlessness per se, activity in a weightless spacecraft, exercizing required to maintain musculoskeletal function, and ataxia problems are dealt with.

Graybiel, A.↗

NASA NTRS1999

Mechanical signaling in the development of postmenopausal osteoporosis

Estrogen deficiency results in increased bone turnover and net bone loss in rats as well as humans. The respective roles of bone turnover and mechanical strain in mediating estrogen deficiency-induced cancellous bone loss were investigated in ovariectomized rats. Ovariectomy resulted in increased bone turnover in long bones. However, cancellous bone was preferentially lost in the metaphysis, a site that experiences low strain energy during normal physical activity. No bone loss was observed in the epiphysis, a site experiencing higher strain energy, despite a similar increase in bone turnover. The role of mechanical strain in maintaining bone balance was investigated by altering the strain history. Mechanical strain was increased or decreased in long bones of ovariectomized rats by treadmill exercise or functional unloading, respectively. Increasing mechanical loading reduced bone loss in the metaphysis. In contrast, decreasing weight bearing accentuated bone loss in the metaphysis and resulted in bone loss in the epiphysis. Finally, administration of estrogen to ovariectomized rats reduced bone loss in unloaded limbs and prevented bone loss in the loaded limbs. These results suggest that estrogen alters the mechanosensory (mechanostat) set point for skeletal adaptation, effectively reducing the minimum strain energy levels at which bone is added. Additionally, these studies suggest that physical activity as well as endocrine status play an important role in maintenance of the female skeleton during aging.

Non-NASA Center↗

NASA NTRS2011

Technology Development to Support Human Health and Performance in Exploration Beyond Low Earth Orbit

In the course of defining the level of risks and mitigating the risks for exploration missions beyond low Earth orbit, NASA s Human Research Program (HRP) has identified the need for technology development in several areas. Long duration missions increase the risk of serious medical conditions due to limited options for return to Earth; no resupply; highly limited mass, power, volume; and communication delays. New space flight compatible medical capabilities required include: diagnostic imaging, oxygen concentrator, ventilator, laboratory analysis (saliva, blood, urine), kidney stone diagnosis & treatment, IV solution preparation and delivery. Maintenance of behavioral health in such an isolated, confined and extreme environment requires new sensory stimulation (e.g., virtual reality) technology. Unobtrusive monitoring of behavioral health and treatment methods are also required. Prolonged exposure to weightlessness deconditions bone, muscle, and the cardiovascular system. Novel exercise equipment or artificial gravity are necessary to prevent deconditioning. Monitoring of the degree of deconditioning is required to ensure that countermeasures are effective. New technologies are required in all the habitable volumes (e.g., suit, capsule, habitat, exploration vehicle, lander) to provide an adequate food system, and to meet human environmental standards for air, water, and surface contamination. Communication delays require the crew to be more autonomous. Onboard decision support tools that assist crew with real-time detection and diagnosis of vehicle and habitat operational anomalies will enable greater autonomy. Multi-use shield systems are required to provide shielding from solar particle events. The HRP is pursuing the development of these technologies in laboratories, flight analog environments and the ISS so that the human health and performance risks will be acceptable with the available resources.

Kundrot, C.E.↗

NASA NTRS2003

Evaluation of NASA Foodbars as a Standard Diet for Use in Short-Term Rodent Space Flight Studies

A standard rodent diet for space flight must meet the unique conditions imposed by the space environment and must be nutritionally adequate since diet can influence the outcome of experiments. This paper evaluates the use of National Aeronautics and Space Administration (NASA) developed Foodbars as a standard space flight diet for rats. The Foodbar's semi-purified formulation permits criteria such as nutrient consistency, high nutrient bioavailability and flexibility of formulation to be met. Extrusion of the semi-purified diet produces Foodbars with the proper texture and a non-crumbing solid form for use in space. Treatment of Foodbar with 0.1% potassium sorbate prevents mold growth. Irradiation (15-25 kGy) prevents bacterial growth and in combination with sorbate-treatment provides added protection against mold for shelf-stability. However, during the development process, nutrient analyses indicated that extrusion and irradiation produced nutrient losses. Nutrients were adjusted accordingly to compensate for processing losses. Nutrient analysis of Foodbars continues to be performed routinely to monitor nutrient levels. It is important that the standard rodent diet provide nutrients that will prevent deficiency but also avoid excess that may mask physiological changes produced by space flight. All vitamins levels in the Foodbars, except for vitamin K conformed to or exceeded the current NRC (1995) recommendations. All indispensable amino acids in Foodbar conformed to or exceeded the NRC nutrient recommendation for mice growth and rat maintenance. However, some indispensable amino acids were slightly below recommendations for rat reproduction/growth. Short-term (18-20 d) animal feeding studies indicated that Foodbars were palatable, supported growth and maintained health in rats. Results indicated that NASA rodent Foodbars meet both the physical and nutritional criteria required to support rodents in the space environment and thus, may be used successfully as a standard diet for short-term space flight studies. However, nutritional adequacy of NASA Rodent Foodbars as a standard diet on longer duration (>20 d) space flight missions remains to be determined.

Tou, Janet↗

NASA NTRS2009

Human Research Program Requirements Document (Revision C)

The purpose of this document is to define, document, and allocate the Human Research Program (HRP) requirements to the HRP Program Elements. It establishes the flow-down of requirements from Exploration Systems Mission Directorate (ESMD) and Office of the Chief Health and Medical Officer (OCHMO) to the various Program Elements of the HRP to ensure that human research and technology countermeasure investments are made to insure the delivery of countermeasures and technologies that satisfy ESMD's and OCHMO's exploration mission requirements. Requirements driving the HRP work and deliverables are derived from the exploration architecture, as well as Agency standards regarding the maintenance of human health and performance. Agency human health and performance standards will define acceptable risk for each type and duration of exploration mission. It is critical to have the best available scientific and clinical evidence in setting and validating these standards. In addition, it is imperative that the best available evidence on preventing and mitigating human health and performance risks is incorporated into exploration mission and vehicle designs. These elements form the basis of the HRP research and technology development requirements and highlight the importance of HRP investments in enabling NASA's exploration missions. This PRD defines the requirements of the HRP which is comprised of the following major Program Elements: Behavioral Health and Performance (BHP), Exploration Medical Capability (ExMC), Human Health Countermeasures (HHC), ISS Medical Project (ISSMP), Space Human Factors and Habitability (SHFH), and Space Radiation (SR).

Vargas, Paul R.↗