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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 NTRS2011

Feasibility Study of an Airbag-Based Crew Impact Attenuation System for the Orion MPCV

Airbag-based methods for crew impact attenuation have been highlighted as a potential lightweight means of enabling safe land-landings for the Orion Multi-Purpose Crew Vehicle, and the next generation of ballistic shaped spacecraft. To investigate the performance feasibility of this concept during a nominal 7.62m/s Orion landing, a full-scale personal airbag system 24% lighter than the Orion baseline has been developed, and subjected to 38 drop tests on land. Through this effort, the system has demonstrated the ability to maintain the risk of injury to an occupant during a 7.85m/s, 0 deg. impact angle land-landing to within the NASA specified limit of 0.5%. In accomplishing this, the airbag-based crew impact attenuation concept has been proven to be feasible. Moreover, the obtained test results suggest that by implementing anti-bottoming airbags to prevent direct contact between the system and the landing surface, the system performance during landings with 0 deg impact angles can be further improved, by at least a factor of two. Additionally, a series of drop tests from the nominal Orion impact angle of 30 deg indicated that severe injury risk levels would be sustained beyond impact velocities of 5m/s. This is a result of the differential stroking of the airbags within the system causing a shearing effect between the occupant seat structure and the spacecraft floor, removing significant stroke from the airbags.

Do, Sydney↗

NASA NTRS2012

NASA In-Space Propulsion Technologies and Their Infusion Potential

The In-Space Propulsion Technology (ISPT) program has been developing in-space propulsion technologies that will enable or enhance NASA robotic science missions. The ISPT program is currently developing technology in four areas that include Propulsion System Technologies (Electric and Chemical), Entry Vehicle Technologies (Aerocapture and Earth entry vehicles), Spacecraft Bus and Sample Return Propulsion Technologies (components and ascent vehicles), and Systems/Mission Analysis. Three technologies are ready for flight infusion: 1) the high-temperature Advanced Material Bipropellant Rocket (AMBR) engine providing higher performance; 2) NASA s Evolutionary Xenon Thruster (NEXT) ion propulsion system, a 0.6-7 kW throttle-able gridded ion system; and 3) Aerocapture technology development with investments in a family of thermal protection system (TPS) materials and structures; guidance, navigation, and control (GN&C) models of blunt-body rigid aeroshells; and aerothermal effect models. Two component technologies that will be ready for flight infusion in the near future will be Advanced Xenon Flow Control System, and ultra-lightweight propellant tank technologies. Future focuses for ISPT are sample return missions and other spacecraft bus technologies like: 1) Mars Ascent Vehicles (MAV); 2) multi-mission technologies for Earth Entry Vehicles (MMEEV) for sample return missions; and 3) electric propulsion for sample return and low cost missions. These technologies are more vehicle-focused, and present a different set of technology infusion challenges. While the Systems/Mission Analysis area is focused on developing tools and assessing the application of propulsion technologies to a wide variety of mission concepts. These in-space propulsion technologies are applicable, and potentially enabling for future NASA Discovery, New Frontiers, and sample return missions currently under consideration, as well as having broad applicability to potential Flagship missions. This paper provides a brief overview of the ISPT program, describing the development status and technology infusion readiness of in-space propulsion technologies in the areas of electric propulsion, aerocapture, Earth entry vehicles, propulsion components, Mars ascent vehicle, and mission/systems analysis.

Anderson, David↗

NASA NTRS2012

NASA In-Space Propulsion Technologies and Their Infusion Potential

Anderson, David J.↗

NASA NTRS2020

TESS Data Release Notes: Sectors 14 – 19, Multi-Sector Search, DR28

This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from the multi-sector search of Sectors 14-19 observed with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.

Burke, Christopher J.↗

NASA NTRSDate not supplied

Gecko Mobility Aids for a Common Habitat Architecture

Spacecraft large enough for crew to move around inside them have traditionally used handrails and foot restraints to enable crew mobility. The mass of this hardware can become significant in large spacecraft such as the Common Habitat. Additionally, handrails and foot restraints in a multi-gravity habitat are trip hazards when the habitat is in a gravity environment. Further, ISS crew have noted risks of breaking ankles and wrists when using handrails for translation and have noted places where not enough handrails are present. Robotic gecko-derived grippers developed by JPL to retrieve satellites can be adapted to crew-worn pads that can adhere to surfaces to enable crew translation in microgravity. This technology will help to eliminate the need for handrails and foot restraints for mobility in crewed microgravity spacecraft cabins. It has the potential to achieve significant mass reductions in future space habitats, with application to suborbital flight, LEO, cislunar space, interplanetary space, the Moon, and Mars. Additionally, it can prevent crew injury and discomfort. Project goals and objectives are to prepare gecko uniform prototypes for use in multi-gravity testing and conduct initial investigations into human factors of postures and motions needed for intravehicular activity (IVA) translation and restraint in multiple gravity environments, without the use of handrails or foot restraints. Gecko grippers have been tested for use as robotic end effectors terrestrially, on microgravity aircraft, and aboard the ISS. Using the grippers as a body-mounted system to achieve IVA crew mobility is a new application that has not been pursued outside of this effort. This work will continue paper studies performed by NASA student interns by developing physical prototypes of spacecraft crew uniforms with gecko-derived body-mounted grippers. Clothing prototypes may include long sleeves, short sleeves, long pants, shorts, gloves, and/or booties equipped with gecko gripper pads. Forward work is to test these uniforms in a 1g environment to verify that the design does not introduce obstructions, trip hazards, or other consequences when used in terrestrial gravity. Based on the 1g test results, the uniform prototypes will be refined, and a test plan developed for testing at 0g, (1/6)g, and (3/8)g.

Restraints and Mobility Aids↗

NASA NTRS2004

Multi-Spectral Cloud Retrievals from Moderate Image Spectrometer (MODIS)

MODIS observations from the NASA EOS Terra spacecraft (1030 local time equatorial sun-synchronous crossing) launched in December 1999 have provided a unique set of Earth observation data. With the launch of the NASA EOS Aqua spacecraft (1330 local time crossing! in May 2002: two MODIS daytime (sunlit) and nighttime observations are now available in a 24-hour period allowing some measure of diurnal variability. A comprehensive set of remote sensing algorithms for cloud masking and the retrieval of cloud physical and optical properties has been developed by members of the MODIS atmosphere science team. The archived products from these algorithms have applications in climate modeling, climate change studies, numerical weather prediction, as well as fundamental atmospheric research. In addition to an extensive cloud mask, products include cloud-top properties (temperature, pressure, effective emissivity), cloud thermodynamic phase, cloud optical and microphysical parameters (optical thickness, effective particle radius, water path), as well as derived statistics. An overview of the instrument and cloud algorithms will be presented along with various examples, including an initial analysis of several operational global gridded (Level-3) cloud products from the two platforms. Statistics of cloud optical and microphysical properties as a function of latitude for land and Ocean regions will be shown. Current algorithm research efforts will also be discussed.

Platnick, Steven↗

NASA NTRS1999

Venus and Beyond Using the Ariane ASAP Launch Capability

The cost of executing planetary missions in the next ten years is expected to decrease significantly. The principle reason is that new technology is reducing spacecraft mass while increasing capability. Another reason is that launch costs are expected to decrease. A move in this direction is to permit important planetary missions to fly as secondary payloads, and this opportunity is now provided by the French on the Ariane 5 using the Ariane Structure for Auxiliary Payloads (ASAP). The ASAP will fly on GEO missions, and can boost up to eight 100 kg (or 200 kg, if paired) payloads into the elliptical geosynchronous transfer orbit (GTO), which delivers large communication satellites to GEO. An efficient multi-burn method has been developed by this author to deliver these small spacecraft from GTO to Mars and other destinations. This method, referred to here as Moon-Earth Gravity Assist (MEGA), requires 3 or more major maneuvers together with close flybys of the earth and moon. An example for a Mars 2003 mission (not to scale) is shown in Figure 1, where, once in GTO, the first burn sends the spacecraft beyond the Moon to a distance of 1.2 million kilometers. At apogee, the second burn targets to an encounter with the Moon such that a swingby returns the spacecraft to the Earth with a 300 km perigee, and with an inclination such that a perigee burn will send the spacecraft off to Mars with the required escape velocity vector. Details of this method, specifically for Mars missions, can be found in Reference 3. A similar strategy works for Venus, with some caveats. This method is required to work for any Ariane 5 launch date over a three month period, to ensure a high probability of getting off the ground. The launch period is provided by fixing the Earth escape date (3rd burn), but allowing the high ellipse (beyond the Moon) period to vary by one or two months, and also allowing a one to two month wait time in GTO (or other orbit) before the first burn is performed. Figure 2 shows the trajectory profiles for the early and late GTO launch dates for a Mars 2003 mission. Venus. which is an inner planet, poses special problems for the MEGA process. The escape direction is reverse that of Earth's motion, and the GTO apogee arrival

Penzo, Paul A.↗

NASA NTRS2022

Multi-Agent Control Approach to the Stability of Linear Deployable Systems

Collisions and undesired dynamic responses may occur during the expansion phase of deployable elements on a spacecraft. This problem is more pronounced in large and complex deployable elements where characterization of transient dynamics using testing and simulation can be challenging. This paper introduces a multi-agent control theory approach to address the problem of collisions and transient behavior in deployable lattice systems. We introduce the graph theoretic and relative error vector-based state-space structures to represent the geometry of a lattice-based deploy system. We show that under the assumption of almost-strict dissipativity, the closed-loop feedback gains of the relative error dynamics are the spring and damper constants in the structure. Moreover, we introduce the control perspective of shaping transient dynamics using eigenstructure assignment and balanced coordinate transformation.

Pablos, Juan L. de↗

NASA NTRSDate not supplied

Autonomous Freeflying Drones for Spacecraft Inspection

Explore the source record for details and available documents.

unmanned aerial vehicle (UAV)↗

NASA NTRS2012

Kennedy Space Center: Creating a Spaceport Reality from the Dreams of Many

On December 17, 1903, Orville Wright piloted the first powered airplane only 20 feet above the ground near Kitty Hawk, North Carolina. The flight lasted 12 seconds and covered 120 feet. Who would have guessed that the bizarre looking contraption developed by brothers in the bicycle business would lay the ground work eventually resulting in over a million passengers moved daily in a sky filled with the contrails of jets flying at over 30,000 feet in elevation and over 500 miles per hour. Similarly, who would have guessed that the destructive nature of V-2 rockets of Germany would spark the genesis of spaceflight to explore our solar system and beyond? Yet the interest in using the Kennedy Space Center (KSC) continues to grow. Potential customers have expressed interest in KSC as a location for testing new rocket engines, servicing the world's largest airborne launching platform for drop-launch rockets, developing multi-use launch platforms that permit diverse customers to use the same launch platform, developing new spacecraft, and implementing advanced modifications for lifting 150 metric ton payloads to low earth orbit. The multitude of customers has grown and with this growth comes a need to provide a command, control, communication, and range infrastructure that maximizes flexibility and reconfigurability to address a much more frequent launch rate of diverse vehicles and spacecraft. The Ground Systems Development and Operations (GSDO) Program Office at KSC is embarking upon these developments to realize the dream of a robust spaceport. Many unique technical trade studies have been completed or are underway to successfully transition KSC into a multi-user customer focused spaceport. Like the evolution of the airplane, GSDO is working to transform KSC infrastructures that will turn once unthinkable space opportunities into a reality for today.

Gray, James A.↗

NASA NTRS1994

SEQ-REVIEW: A tool for reviewing and checking spacecraft sequences

A key component of JPL's strategy to make space missions faster, better and cheaper is the Advanced Multi-Mission Operations System (AMMOS), a ground software intensive system currently in use and in further development. AMMOS intends to eliminate the cost of re-engineering a ground system for each new JPL mission. This paper discusses SEQ-REVIEW, a component of AMMOS that was designed to facilitate and automate the task of reviewing and checking spacecraft sequences. SEQ-REVIEW is a smart browser for inspecting files created by other sequence generation tools in the AMMOS system. It can parse sequence-related files according to a computer-readable version of a 'Software Interface Specification' (SIS), which is a standard document for defining file formats. It lets users display one or several linked files and check simple constraints using a Basic-like 'Little Language'. SEQ-REVIEW represents the first application of the Quality Function Development (QFD) method to sequence software development at JPL. The paper will show how the requirements for SEQ-REVIEW were defined and converted into a design based on object-oriented principles. The process starts with interviews of potential users, a small but diverse group that spans multiple disciplines and 'cultures'. It continues with the development of QFD matrices that related product functions and characteristics to user-demanded qualities. These matrices are then turned into a formal Software Requirements Document (SRD). The process concludes with the design phase, in which the CRC (Class, Responsibility, Collaboration) approach was used to convert requirements into a blueprint for the final product.

Maldague, Pierre F.↗

NASA NTRS2016

Europa Spacecraft Configuration Optimization for the Solar Powered Vehicle

A mission to Europa has been on the minds of NASA and JPL for many years. After the Galileo mission to Jupiter in the 1990s there have been various proposals for missions to the Jovian moon. The most recent proposal, previously named the Europa Clipper, has gone through numerous iterations of spacecraft configurations on its road to becoming an official NASA project in June of 2015. Most of these configurations included options for either multi mission radioisotope thermoelectric generators (MMRTGs) or solar power. In 2014, the decision was made to focus on solar arrays as the source for spacecraft power. The decision to move forward with a baseline design that utilized only solar arrays as its power system meant that some configuration choices had to be re- evaluated. Initially, a configuration was adapted to keep as much of the previous spacecraft design the same while replacing MMRTGs with solar panels. This proved to be difficult as the arrays presented a slew of new challenges that the nuclear vehicle was not optimized for. The solar arrays needed to be large due to Jupiter's substantial distance from the Sun. This meant that many of the instrument and radiator FOVs would now be obstructed, or would receive reflected light and heat from the large panel s. Also, the mass of the panels meant that mounting near the bottom of the spacecraft would be sub-optimal as the wings would cause major disturbance to the vehicle as they oscillated in their deployed state. Another major, and possibly the largest, concern was the fact that as the high gain antenna pointed to Earth for communication, the Ice Penetrating Radar (IPR) would cast a large shadow on the cell -side of the array. This resulted in an estimated 10% power loss to the vehicle. On top of all this, NASA announced the selection of the instruments that would fly on the Europa mission and replace the notional instrument suite that had been used to develop and submit the project proposal. The selected instruments, while not varying widely from the notional suite, did come with a new set of challenges including a size increase over the notional package, thus requiring more room for accommodation. They also introduced new features not previously addressed by the notional package, such as a two-axis gimbal on one of the imagers. Additionally, two new instruments, an ultraviolet plume -hunting spectrograph, and an atmospheric dust analyzer we added to the payload and presented new challenges not previously covered in the proposal. Finally, additional payloads were under consideration, such as a 250kg ejectable payload that would be released at Jupiter and would accomplish flybys of some of the other Jovian moons. All of this resulted in a drastically different "family" of configurations that were capable of addressing these issues, and staying flexible to the numerous potential changes that could come. This paper discusses the details of the various configurations considered to address these items, and the configuration concepts that were selected as the baseline for moving forward with the proposal.

Horner, Matthew D.↗

NASA NTRS2001

A Second Generation Multi-Angle Imaging SpectroRadiometer (MISR-2)

The Multi-angle Imaging SpectroRadiometer (MISR) has been in Earth orbit since December 1999 on NASA's Terra spacecraft. This instrument provides new ways of looking at the Earth's atmosphere, clouds, and surface for the purpose of understanding the Earth's ecology, environment, and climate. To facilitate the potential future continuation of MISR's multi-angle observations, a study was undertaken in 1999 and 2000 under the Instrument Incubator Program (IIP) of NASA Code Y's Earth Science Technology Office (ESTO) to investigate and demonstrate the feasibility of a successor to MISR that will have greatly reduced size and mass. The kernel of the program was the design, construction, and testing of a highly miniaturized camera, one of the nine that would probably be used on a future space borne MISR-like instrument. This demonstrated that the size and mass reduction of the optical system and camera electronics are possible and that filters can be assembled to meet the miniaturized packaging requirements. An innovative, reflective optics design was used, enabling the wavelength range to be extended into the shortwave infrared. This was the smallest all-reflective camera ever produced by the contractor. A study was undertaken to determine the feasibility of implementing nine (multi-angle) cameras within a single structure. This resulted in several possible configurations. It would also be possible to incorporate one of the cameras into an airborne instrument.

spectroradiometers↗

NASA NTRS2018

Development and Testing of a Vehicle Management System for Autonomous Spacecraft Habitat Operations

As the increased distance between Earth-based mission control and the spacecraft results in increasing communication delays, small crews cannot take on all functions performed by ground today, and so vehicles must be more automated to reduce the crew workload for such missions. In addition, both near-term and future missions will feature significant periods when crew is not present, meaning the vehicles will need to operate themselves autonomously. NASA's Advanced Exploration Systems Program pioneers new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond low-Earth orbit. Under this program, NASA has developed and demonstrated multiple technologies to enable the autonomous operation of a dormant space habitat. These technologies included a fault-tolerant avionics architecture, novel spacecraft power system and power system controller, and autonomy software to control the habitat. The demonstration involved simulation of the habitat and multiple spacecraft sub-systems (power storage and distribution, avionics, and air-side life-support) during a multi-day test at NASA's Johnson Space Center. The foundation of the demonstration was â€˜quiescent operations' of a habitat during a 55 minute eclipse period. For this demonstration, the spacecraft power distribution system and air-side life support system were simulated at a high level of fidelity; additional systems were managed, but with lower fidelity operational constraints and system behavior. Operational constraints for real and simulated loads were developed by analyzing on-orbit hardware and evaluating future Exploration capable technology. A total of 13 real and simulated loads were used during the test. Eight scenarios including both nominal and off-nominal conditions were performed. Over the course of the test, every application performed its desired functions successfully during the simulated tests. The results will inform both future tests, as well as provide insight to NASA's domestic and international partners, as they construct the next generation of space habitats to be used on beyond-Earth missions.

Autonomous Systems and Operations↗

NASA NTRS2016

Robust Thermal Control of Propulsion Lines for Space Missions

In spacecraft that have propulsion lines that are located externally with open bus architecture, the lines are typically insulated by Multi Layer Insulation (MLI) blankets to protect them thermally from the cold space environment. In addition to heat loss through the insulation, mechanical supports used to attach the lines to the spacecraft structure also create heat leaks from the lines. These lines typically have very low thermal conduction in the axial direction, so the heat balance in the lines tends to be very local without much heat spreading. The typical allowable temperature range for hydrazine-based lines is +15/+50°C. This tight temperature range has to be maintained for every location on these lines. For typical spacecraft, these lines can be several meters long. Temperature control is typically achieved by closed loop monitoring of temperatures along the lines and the corresponding powering of the heaters in a bang-bang approach to maintain the temperatures within the dead band of the control loop. The temperatures of propulsion lines are a function of several parameters with heat loss characteristics of the MLI being the key one. Unfortunately, this same key characteristic (MLI effective emittance) has a large variation along its length due to its dependence on workmanship, which in turn leads to large uncertainties in the propulsion lines’ local temperatures. Because of the poor conduction along the axial direction, heat balance along the length varies dramatically from one location to the next, even few inches apart, depending on the combination of the controlling parameters. This paper describes various robust design and implementation approaches that have been investigated to greatly reduce the randomness associated with predicting the temperature of these propulsion lines.

Bhandari, Pradeep↗

NASA NTRS2001

Using abstraction in multi-rover scheduling

r describes how an iterative repair planner/scheduler can reason about the activities of multiple spacecraft at abstract levels in order to greatly improve the scheduling of their use of shared resources.

abstraction planning rovers multiple agents↗

NASA NTRS2013

Composite Design and Manufacturing Development for Human Spacecrafts

The Structural Engineering Division at the NASA Johnson Space Center (JSC) has begun work on lightweight, multi‐functional pressurized composite structures. The first candidate vehicle for technology development is the Multi‐Mission Space Exploration Vehicle (MMSEV) cabin, known as the Gen 2B cabin, which has been built at JSC by the Robotics Division. Of the habitable MMSEV vehicle prototypes designed to date, this is the first one specifically analyzed and tested to hold internal pressure and the only one made out of composite materials. This design uses a laminate base with zoned reinforcement and external stringers, intended to demonstrate certain capabilities, and to prepare for the next cabin design, which will be a composite sandwich panel construction with multi‐functional capabilities. As part of this advanced development process, a number of new technologies were used to assist in the design and manufacturing process. One of the methods, new to JSC, was to build the Gen 2B cabin with Out of Autoclave technology to permit the creation of larger parts with fewer joints. An 8‐ply pre‐preg layup was constructed to form the cabin body. Prior to lay‐up, a design optimization software called FiberSIM was used to create each ply pattern. This software is integrated with Pro/Engineer to allow for customized draping of each fabric ply over the complex tool surface. Slits and darts are made in the software model to create an optimal design that maintains proper fiber placement and orientation. The flat pattern of each ply is then exported and sent to an automated cutting table where the patterns are cut out of graphite material. Additionally, to assist in lay‐up, a laser projection system (LPT) is used to project outlines of each ply directly onto the tool face for accurate fiber placement and ply build‐up. Finally, as part of the OoA process, a large oven was procured to post‐cure each part. After manufacturing complete, the cabin underwent modal and pressure testing (currently in progress at date of writing) and will go on to be outfitted and used for further ops usage.

Litteken, Douglas↗

NASA NTRS2012

Vlasov Simulation of Electrostatic Solitary Structures in Multi-Component Plasmas

Electrostatic solitary structures have been observed in the Earth's magnetosheath by the Cluster spacecraft. Recent theoretical work has suggested that these solitary structures are modeled by electron acoustic solitary waves existing in a four-component plasma system consisting of core electrons, two counter-streaming electron beams, and one species of background ions. In this paper, the excitation of electron acoustic waves and the formation of solitary structures are studied by means of a one-dimensional electrostatic Vlasov simulation. The present result first shows that either electron acoustic solitary waves with negative potential or electron phase-space holes with positive potential are excited in four-component plasma systems. However, these electrostatic solitary structures have longer duration times and higher wave amplitudes than the solitary structures observed in the magnetosheath. The result indicates that a high-speed and small free energy source may be needed as a fifth component. An additional simulation of a five-component plasma consisting of a stable four-component plasma and a weak electron beam shows the generation of small and fast electron phase-space holes by the bump-on-tail instability. The physical properties of the small and fast electron phase-space holes are very similar to those obtained by the previous theoretical analysis. The amplitude and duration time of solitary structures in the simulation are also in agreement with the Cluster observation.

magnetohydrodynamics (MHD)↗