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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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NASA NTRS2001

Hubble Space Telescope Servicing Mission 3A Rendezvous Operations

The Hubble Space Telescope (HST) hardware complement includes six gas bearing, pulse rebalanced rate integrating gyros, any three of which are sufficient to conduct the science mission. After the loss of three gyros between April 1997 and April 1999 due to a known corrosion mechanism, NASA decided to split the third HST servicing mission into SM3A, accelerated to October 1999, and SM3B, scheduled for November 2001. SM3A was developed as a quick turnaround 'Launch on Need' mission to replace all six gyros. Loss of a fourth gyro in November 1999 caused HST to enter Zero Gyro Sunpoint (ZGSP) safemode, which uses sun sensors and magnetometers for attitude determination and momentum bias to maintain attitude stability during orbit night. Several instances of large attitude excursions during orbit night were observed, but ZGSP performance was adequate to provide power-positive sun pointing and to support low gain antenna communications. Body rates in ZGSP were estimated to exceed the nominal 0.1 deg/sec rendezvous limit, so rendezvous operations were restructured to utilize coarse, limited life, Retrieval Mode Gyros (RMGs) under Hardware Sunpoint (HWSP) safemode. Contingency procedures were developed to conduct the rendezvous in ZGSP in the event of RMGA or HWSP computer failure. Space Shuttle Mission STS-103 launched on December 19, 1999 after a series of weather and Shuttle-related delays. After successful rendezvous and grapple under HWSP/RMGA, the crew changed out all six gyros. Following deploy and systems checkout, HST returned to full science operations.

Lee, S.↗
NASA NTRS1998

Risk Management Structured for Today's Environment

Today's project management environment provides NASA with myriad challenges. We have smaller budgets and, consequently, smaller programs and shorter lead times. We have less money for development, and no money to recover from contingencies or mishaps. The NASA Administrator is leading the Agency away from operations, instilling a renewed focus on scientific research and the development and application of new cutting-edge technologies. We are using performance-based and fixed-price contracts with industry, and we are forming more and more partnerships with the international community. In addition to the environment, we have many NASA-unique conditions that challenge mission success. They include a higher level of performance requirements, limited production numbers, higher development efforts and cost, the inability to operate a space element fully under realistic conditions on the ground, limited access to the product during operation, and, of course, the need for more science for fewer dollars and on a shorter schedule.

Michael A. Greenfield↗
NASA NTRS1972

Apollo 16 Press Kit

The Apollo 16 spacecraft is scheduled for launch on Apr. 16, 1972 from Complex 39A at the Kennedy Space Center, Florida by the Saturn V launch vehicle. Crewmen are mission commander John W. Young, command module pilot Thomas K. Mattingly II and lunar module pilot Charles M. Duke Jr. Objectives of the mission, to last up to 12 days, as outlined by NASA: to perform selenological inspection, survey and sampling of materials in a preselected region of Descartes using a lunar roving' vehicle; deploy and activate Apollo surface experiments; develop man's capability to work in the lunar environment; obtain photographs of candidate exploration sites; and toconduct inflight experiments and photographic tasks in lunar orbit. Following launch, the spacecraft will reach Earth Parking Orbit and remain in orbit for about two and one-half revolutions prior to Translunar Injection. Next, the Command and Service Module docks with the Lunar Module and the spacecraft "coasts" to the moon. In orbit around the moon, the Command and Service Module/Lunar Module combination will descend to within 50,000 feet of the lunar surface before undocking. The Lunar Module will continue to descend while the Command and Service Module returns to an orbit approximately 60 miles high. Stay time on the lunar surface is scheduled for approximately 73 hours. The ascent stage of the Lunar Module then lifts the astronauts back into lunar orbit where they will dock with the Command/Service Module. The Lunar Module is jettisoned and Transearth Injection follows. Just prior to reentry into the earth's atmosphere, the Service Module is jettisoned, and the astronauts in the Command Module splashdown in the Pacific Ocean. The target point for end-of-mission splashdown is at 05 degrees 0 minutes north latitude and 158 degrees 40 minutes west longitude or approximately 985 nautical miles south of Honolulu, Hawaii. Splashdown is scheduled for Apr. 28, 1972 at 10:30 a.m. Hawaiian Standard Time (2:30 p.m. CST). Recovery forces for Apollo 16, stationed in both the Atlantic and Pacific Oceans, will consist of three ships, nine aircraft and nearly 1,700 personnel. CTF-130 (Manned Spacecraft Recovery Force, Pacific) forces will be stationed south of Hawaii. Three ships, eight helicopters and three Air Force HC-130H aircraft, and nearly 1,100 personnel, will take part. Task Force 140 (Manned Spacecraft Recovery Force, Atlantic), comprising one ship, six HC-130H aircraft, three helicopters and approximately 300 personnel, will be positioned for possible launch abort operations. Two ships in the Atlantic will also be used for acoustical testing. Other forces, primarily aircraft and personnel of the Air Force Aerospace Rescue and Recovery Service will be on alert around the world for contingency recovery support.

Source record↗
NASA NTRS2022

Recommendations for Developing Space Suit Integrated Food Systems and Delivering Nutrition Before, During, and After Lunar EVA

The concept of providing hydration and nutrition during extravehicular activity (EVA) is nearly as old as the space program itself. Astronauts currently have access to 32 ounces of water through a disposable in-suit drink bag (DIDB) while they are confined to their space suit. During the Apollo program, methods for providing food/nutrition to crewmembers in space suits were included as contingency solutions (1) but were eventually abandoned. The main reasons that provision of in-suit nutrition beyond water was discontinued after Apollo were the complicated engineering requirements, the additional mass and volume that was required for the applicable food formulations, hardware needed for a suit-specialized food system, and because the perceived need for in-suit nutrition during EVAs was not sufficient during the Space Shuttle and the International Space Station (ISS) eras. A custom-made 165-kcal fruit bar was fitted into the EVA suit during the Space Shuttle program, but crewmembers rarely consumed it during the EVA and rather chose to consume it before or after suited activities (2). Since 2011, between 4 and 13 EVAs have been conducted from the ISS each year, with durations ranging from 1:32 to 8:17 hours (https://www.nasa.gov/mission_pages/station/spacewalks ). It has been acceptable for the crewmembers to schedule food intake around these relatively infrequent suited activities. Because upcoming Artemis missions will include nominal 8-hour lunar exploration EVAs that are expected to increase in frequency to several (4 to 5) sorties per week (3), the desire for an in-suit nutrition system has increased. In preparation for these missions, requirements to provide in-suit nutrition has been outlined in the most recent NASA Human Spaceflight Standards documents (4). Establishing general recommendations for in-suit nutrition systems precedes the selection of a lunar EVA pressure suit system. The current document is intended to define the rationale for nutrition to support EVA (whether in-suit or from the pantry in the habitat), document the requirements, constraints, and crewmember preferences, and recommend necessary next steps for developing an in-suit EVA nutrition system. Assessments presented in this report include a review of commercial off-the-shelf (COTS) food products as potential in-suit formulations, a comparison of conceptual designs for delivering nutrition to a crewmember while confined to a space suit, an evaluation of space suit volume constraints for the placement of in-suit nutrition systems, and feedback from astronauts regarding preferences for nutrition support during EVA. Based on these assessments, recommendations were formulated that can be used to help develop a method to deliver nutrition safely and acceptably to a crewmember while they are confined to a space suit for an EVA duration of up to 8 hours, and a total time in the suit of up to 12 hours.

space suit↗
NASA NTRS2020

Artificial Gravity in Mars Orbit for Crew Acclimation

NASA’s current baseline plan for a crewed Mars mission anticipates a transit time of up to three hundred days in microgravity and 3-14 days on the Martian surface for gravity acclimation before the crew can safely perform their first Extra-Vehicular Activity (EVA). While there are multiple options for how initial surface operations will be performed, all current designs involve acclimation on the surface, and the impacts on the mission schedule, required supplies, and crew lander systems are significant. This paper proposes an alternative option utilizing artificial gravity, which offers benefits in terms of mission scope, mass savings, crew health, and long-term strategic vision. By moving the acclimation requirement to the orbiting habitat’s existing systems, rather than adding redundant systems to the lander, the Mars Descent Vehicle (MDV) can be a much smaller, simpler, and lighter design. Rather than the lander being designed to support crew for days, it would be mere hours. While ambitious, the concept of pre-acclimation in orbit can be not only safe and feasible, but done with fairly minimal changes to the planned architecture and overall mass requirements. The data used draws on decades of established research and demonstrates how this capability can be not only used for pre-acclimation, but also to support crew during early orbital-only missions, surface abort contingency scenarios, return-to-orbit abort scenarios, and as an early proof of capability into larger and more ambitious artificial gravity designs needed for extended exploration missions in the future.

Rowe, Justin↗
NASA NTRS2017

Development of the European Service Module Propulsion Subsystem for the Multi-Purpose Crew Vehicle

Hardware Heritage Schedule limitations and budget constraints drove the need for extensive use of heritage hardware designs. In some cases (OMS and TVC) flight hardware reuse (from Shuttle) was required,and will be delta-qualified for use on Orion Primary sources of heritage: ATV Shuttle Orion CM PSS Ariane 5 EPS Targeted Development Testing Component development testing was performed to address the highest risk areas of heritage design compliance with Orion requirements Assembly level development testing was performed to understand complex assemblies and component interactions Heritage Direct re-use of assets from Shuttle Orbiters, all assets have varying flight history. Orion Use Used by Orion to gimbal the main engine during major translational maneuvers Development Testing Random vibration on controller box (lead to card retention design mod) Design Changes (only as required) Circuit board retention in controller box (single instance from Shuttle flight history) New, longer harnesses Basic Specs(8) fixed position engines Thrust: 105 lbf Nozzle area ratio: 164:1 Orion Use Nominally used for separation maneuvers and mid-course correction maneuvers In contingency scenario (failed main engine), used for major translational maneuvers Drives the need for long continuous duration firing Drives the need for off-pulsing (to steer) Control authority requires 50 duty cycle Development Testing Random Vibration (added vibration isolation bracket) Hot fire, duty cycle (changed MR)

pressure fed↗
NASA NTRS2017

SPHERES and Astrobee: Space Station Robotic Free Flyers

Free-flying space robots can be used when humans are present to off-load routine work, to increase astronaut productivity, and to handle contingencies. The International Space Station (ISS), for example, is a continuously manned orbital laboratory the size of a large house, which contains many thousands of inventory items and hundreds of diverse payloads and experiments - all of which have to be managed by 6 person crew. To help with this, NASA is developing and testing robotic free-flyers on the ISS. SPHERES (Synchronized Position Hold, Engage, Reorient, Experimental Satellites) is an ISS facility with three nano-satellites designed to research estimation, control, and autonomy algorithms. SPHERES are volleyball-sized, have their own power, propulsion and navigation systems, and work on the ISS under astronaut supervision. For more than 10 years, NASA has made SPHERES available to other U.S. government agencies, schools, commercial companies and students as a platform for science, technology development, and education. SPHERES will soon be succeeded by the new Astrobee free-flying robot. Astrobee builds on the success of SPHERES, but in addition to research, the robot will also be used for housekeeping and monitoring duties without astronaut supervision. Astrobee makes extensive use of open-source (the complete software stack is available on GitHub) and is scheduled to be installed on the ISS in late Spring 2018.

Benavides, Jose V.↗
NASA NTRS1999

Aerospace Safety Advisory Panel

This report covers the activities of the Aerospace Safety Advisory Panel (ASAP) for calendar year 1998-a year of sharp contrasts and significant successes at NASA. The year opened with the announcement of large workforce cutbacks. The slip in the schedule for launching the International Space Station (ISS) created a 5-month hiatus in Space Shuttle launches. This slack period ended with the successful and highly publicized launch of the STS-95 mission. As the year closed, ISS assembly began with the successful orbiting and joining of the Functional Cargo Block (FGB), Zarya, from Russia and the Unity Node from the United States. Throughout the year, the Panel maintained its scrutiny of NASAs safety processes. Of particular interest were the potential effects on safety of workforce reductions and the continued transition of functions to the Space Flight Operations Contractor. Attention was also given to the risk management plans of the Aero-Space Technology programs, including the X-33, X-34, and X-38. Overall, the Panel concluded that safety is well served for the present. The picture is not as clear for the future. Cutbacks have limited the depth of talent available. In many cases, technical specialties are "one deep." The extended hiring freeze has resulted in an older workforce that will inevitably suffer significant departures from retirements in the near future. The resulting "brain drain" could represent a future safety risk unless appropriate succession planning is started expeditiously. This and other topics are covered in the section addressing workforce. In the case of the Space Shuttle, beneficial and mandatory safety and operational upgrades are being delayed because of a lack of sufficient present funding. Likewise, the ISS has little flexibility to begin long lead-time items for upgrades or contingency planning.

Source record↗
NASA NTRSDate not supplied

Manual Crew Override of Vehicle Landings Following G-Transitions

BACKGROUND Manual control during exploration spaceflight consists of both planned automated supervisory control and unplanned crew override. This crew override capability is critical to enable overall mission success during landing contingencies. However, the introduction of manual override capabilities must be implemented to enable crews to mitigate risks introduced by human error. Adaptive changes in the sensorimotor system can manifest during g-transitions as spatial disorientation. While training and landing aids enable successful landing through disorientation, these adaptive changes may increase cognitive demand that needs to be accounted for in the manual control strategy. It is important to characterize these effects as soon as possible following the G-transition to develop appropriate countermeasures. METHODS The following study seeks to inform the risk associated with altered sensorimotor and vestibular function impacting critical mission tasks. We aim to characterize the effects of short and long-duration weightlessness on manual control following G-transitions using simulated lunar landing on a six-degree-of-freedom (6DOF) motion base, a fixed base simulation, and a supervisory control tablet task. The primary goal is to understand the impact of spaceflight on crew ability to perform manual crew override and supervisory control. This aim will be assessed by comparing pre- versus postflight simulation performance in crewmembers assigned to either short duration (< 30 day) or long duration (~6- month) missions to the International Space Station (ISS). We hypothesize there will be postflight increases in the percent time that pilots are outside of the acceptable range for recommended vehicle state parameters and the reaction time for secondary cognitive tasks. Ground-based control subjects, who are demographically matched to the crew considering age (± 5 years) and gender, will undergo the same testing schedule as the crew to examine the effects of flight phase independent of microgravity exposure. The second aim is to examine how adaptive changes in vestibular and cognitive function relate to changes in manual crew override proficiency. Crew performance for a sensorimotor perceptual test battery will evaluate motion perception tracking, roll nulling, and/or vection sensitivity using the 6DOF motion base. We hypothesize that a higher severity of vestibular alterations will be associated with increased percent time outside of guidance limits. Motion sickness severity and sleepiness will also be evaluated. To determine the impact of “just-in-time” training, the third aim seeks to compare performance during on-board lunar landing tasks conducted late in-flight to early postflight. We hypothesize that proficiency on the “just-in-time” laptop trainer late in mission will be positively correlated with early postflight proficiency on the same task. The final aim will establish assessments of performance, training protocols, and the learning progression in a ground-control cohort of first-time users. RESULTS The assessment of the learning progression associated with the piloting task on the motion base system with thirty ground subjects will be reported. Learning curves will be established across four distinct sessions and within session considering trial difficulty. The difficulty of the landing task can be modulated with the landing divert distance and cross or downrange difficulty. Results may include changes in performance across multiple trials of a multi-attribute lunar tablet supervisory control task. Preliminary investigations of eighteen subjects who completed vestibular threshold and motion perception tasks offer expected performance ranges for upcoming preflight crew evaluations. The results yielded an average roll threshold of 0.46 ± 0.30 deg/s and an average roll nulling root mean square error performance of 2.52 ± 0.52 deg/s. RELEVANCE This project will deliver an operational demonstration of crew monitoring capability following spaceflight and identify potential deficits that may require remediation. Comparison of individual vestibular and cognitive changes with crew performance will help better characterize the manual control risks associated with sensorimotor alterations. Ground testing will evaluate learning progression, refine training protocols, and serve as a control cohort for comparisons to crew performance. ACKNOWLEDGEMENTS: The authors acknowledge contributions from Draper, the Dynamic Skills Trainer (DST) Lab, and the Software, Robotics, and Simulation Division toward the development of the lunar landing simulation platforms. This project is funded by the Human Health Countermeasures Element.

Hannah M. Weiss↗
NASA NTRS2013

First Results from NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE)

As of early August, 2013, the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission is scheduled for launch on a Minotaur V rocket from Wallops Flight Facility during a five-day launch period that opens on Sept. 6, 2013 (early Sept. 7 UTC). LADEE will address 40 year-old mysteries of the lunar atmosphere and the question of levitated lunar dust. It will also pioneer the next generation of optical space communications. LADEE will assess the composition of the lunar atmosphere and investigate the processes that control its distribution and variability, including sources, sinks, and surface interactions. LADEE will also determine whether dust is present in the lunar exosphere, and reveal its sources and variability. These investigations are relevant to our understanding of surface boundary exospheres and dust processes occurring at many objects throughout the solar system, address questions regarding the origin and evolution of lunar volatiles, and have potential implications for future exploration activities. Following a successful launch, LADEE will enter a series of phasing orbits, which allows the spacecraft to arrive at the Moon at the proper time and phase. This approach accommodates any dispersion in the Minotaur V launch injection. LADEE's arrival at the moon in early October. The spacecraft will approach the moon from its leading edge, travel behind the Moon out of sight of the Earth, and then re-emerge and execute a three-minute Lunar Orbit Insertion maneuver. This will place LADEE in an elliptical retrograde equatorial orbit with an orbital period of approximately 24 hours. A series of maneuvers is then performed to reduce the orbit to become nearly circular with a 156-mile (250- kilometer) altitude. Spacecraft checkout and science instrument commissioning will commence in early-October and will nominally span 30 days but can be extended for an additional 30 days in the event of contingencies. Following commissioning, the 100-day Science Phase is performed at an orbit with periapsis between 20-60 km. This orbit must be constantly managed due to the Moon's highly inhomogeneous gravity field. During the Science Phase, the moon will rotate more than three times underneath the LADEE orbit. LADEE employs a high heritage instrument payload: a Neutral Mass Spectrometer (NMS) from Goddard Space Flight Center, an Ultraviolet/Visible Spectrometer (UVS) from Ames Research Center, and a dust detection experiment (LDEX) from the University of Colorado/LASP. It will also carry the Lunar Laser Communications Demonstration (LLCD) as a technology demonstration. The LLCD is funded by the Human Exploration Operations Mission Directorate (HEOMD), managed by GSFC, and built by the MIT Lincoln Lab. Contingent upon LADEE's successful lunar orbit insertion and checkout, we will report the early results from the science investigations.

Moon↗
NASA NTRS1994

Microgravity Flight - Accommodating Non-Human Primates

Spacelab Life Sciences-3 (SLS-3) was scheduled to be the first United States man-tended microgravity flight containing Rhesus monkeys. The goal of this flight as in the five untended Russian COSMOS Bion flights and an earlier American Biosatellite flight, was to understand the biomedical and biological effects of a microgravity environment using the non-human primate as human surrogate. The SLS-3/Rhesus Project and COSMOS Primate-BIOS flights all utilized the rhesus monkey Macaca mulatta. The ultimate objective of all flights with an animal surrogate has been to evaluate and understand biological mechanisms at both the system and cellular level, thus enabling rational effective countermeasures for future long duration human activity under microgravity conditions and enabling technical application to correction of common human physiological problems within earth's gravity, e.g., muscle strength and reloading, osteoporosis, immune deficiency diseases. Hardware developed for the SLS-3/Rhesus Project was the result of a joint effort with the French Centre National d'Etudes Spatiales (CNES) and the United States National Aeronautics and Space Administration (NASA) extending over the last decade. The flight hardware design and development required implementation of sufficient automation to insure flight crew and animal bio-isolation and maintenance with minimal impact to crew activities. A variety of hardware of varying functional capabilities was developed to support the scientific objectives of the original 22 combined French and American experiments, along with 5 Russian co-investigations, including musculoskeletal, metabolic, and behavioral studies. Unique elements of the Rhesus Research Facility (RRF) included separation of waste for daily delivery of urine and fecal samples for metabolic studies and a psychomotor test system for behavioral studies along with monitored food measurement. As in untended flights, telemetry measurements would allow monitoring of thermoregulation, muscular, and cardiac responses to weightlessness. In contrast, the five completed Cosmos/Bion flights, lacked the metabolic samples and behavioral task monitoring, but did facilitate studies of the neurovestibular system during several of the flights. The RRF accommodated two adult 8-11 kg rhesus monkeys, while the Russian experiments and hardware were configured for a younger animal in the 44 kg range. Both the American and Russian hardware maintained a controlled environmental system, specifically temperature, humidity, a timed lighting cycle, and had means for providing food and fluids to the animal(s). Crew availability during a Shuttle mission was to be an optimal condition for retrieval and refrigeration of the animal urine samples along with a manual calcein injection which could lead to greater understanding of bone calcium incorporation. A special portable bioisolation glove box was under development to support this aspect of the experiment profile along with the capability of any contingency human intervention. As a result of recent U.S./Russian negotiations, funding for Space Station, and a series of other events, the SLS-3 mission was cancelled and applicable Rhesus Project experiments incorporated into the Russian Bion 11 and 12 missions. A presentation of the RRF and COSMOS/Bion rhesus hardware is presented along with current plans for the hardware.

Dalton, Bonnie P.↗
NASA NTRS1995

Microgravity Flight: Accommodating Non-Human Primates

Spacelab Life Sciences-3 (SLS-3) was scheduled to be the first United States man-tended microgravity flight containing Rhesus monkeys. The goal of this flight as in the five untended Russian COSMOS Bion flights and an earlier American Biosatellite flight, was to understand the biomedical and biological effects of a microgravity environment using the non-human primate as human surrogate. The SLS-3/Rhesus Project and COSMOS Primate-BIOS flights all utilized the rhesus monkey, Macaca mulatta. The ultimate objective of all flights with an animal surrogate has been to evaluate and understand biological mechanisms at both the system and cellular level, thus enabling rational effective countermeasures for future long duration human activity under microgravity conditions and enabling technical application to correction of common human physiological problems within earth's gravity, e.g., muscle strength and reloading, osteoporosis, immune deficiency diseases. Hardware developed for the SLS-3/Rhesus Project was the result of a joint effort with the French Centre National d'Etudes Spatiales (CNES) and the United States National Aeronautics and Space Administration (NASA) extending over the last decade. The flight hardware design and development required implementation of sufficient automation to insure flight crew and animal bio-isolation and maintenance with minimal impact to crew activities. A variety of hardware of varying functional capabilities was developed to support the scientific objectives of the original 22 combined French and American experiments, along with 5 Russian co-investigations, including musculoskeletal, metabolic, and behavioral studies. Unique elements of the Rhesus Research Facility (RRF) included separation of waste for daily delivery of urine and fecal samples for metabolic studies and a psychomotor test system for behavioral studies along with monitored food measurement. As in untended flights, telemetry measurements would allow monitoring of thermoregulation, muscular, and cardiac responses to weightlessness. In contrast, the five completed Cosmos/Bion flights, lacked the metabolic samples and behavioral task monitoring, but did facilitate studies of the neurovestibular system during several of the flights. The RRF accommodated two adult 8-11 kg rhesus monkeys, while the Russian experiments and hardware were configured for a younger animal in the 44 kg range. Both the American and Russian hardware maintained a controlled environmental system, specifically temperature, humidity, a timed lighting cycle, and had means for providing food and fluids to the animal(s). Crew availability during a Shuttle mission was to be an optimal condition for retrieval and refrigeration of the animal urine samples along with a manual calcein injection which could lead to greater understanding of bone calcium incorporation. A special portable bioisolation glove box was under development to support this aspect of the experiment profile along with the capability of any contingency human intervention. As a result of recent U.S./Russian negotiations, funding for Space Station, and a series of other events, the SLS-3 mission was cancelled and applicable Rhesus Project experiments incorporated into the Russian Bion 11 and 12 missions. A presentation of the RRF and COSMOS/Bion rhesus hardware is presented along with current plans for the hardware.

Dalton, Bonnie P.↗