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

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At least 739 records · Page 41
All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

A Near-Infrared and Thermal Imager for Mapping Titan's Surface Features

Approximately 10% of the solar insolation reaches the surface of Titan through atmospheric spectral windows. We will discuss a filter based imaging system for a future Titan orbiter that will exploit these windows mapping surface features, cloud regions, polar storms. In the near-infrared (NIR), two filters (1.28 micrometer and 1.6 micrometer), strategically positioned between CH1 absorption bands, and InSb linear array pixels will explore the solar reflected radiation. We propose to map the mid, infrared (MIR) region with two filters: 9.76 micrometer and 5.88-to-6.06 micrometers with MCT linear arrays. The first will map MIR thermal emission variations due to surface albedo differences in the atmospheric window between gas phase CH3D and C2H4 opacity sources. The latter spans the crossover spectral region where observed radiation transitions from being dominated by thermal emission to solar reflected light component. The passively cooled linear arrays will be incorporated into the focal plane of a light-weight thin film stretched membrane 10 cm telescope. A rad-hard ASIC together with an FPGA will be used for detector pixel readout and detector linear array selection depending on if the field-of-view (FOV) is looking at the day- or night-side of Titan. The instantaneous FOV corresponds to 3.1, 15.6, and 31.2 mrad for the 1, 5, and 10 micrometer channels, respectively. For a 1500 km orbit, a 5 micrometer channel pixel represents a spatial resolution of 91 m, with a FOV that spans 23 kilometers, and Titan is mapped in a push-broom manner as determined by the orbital path. The system mass and power requirements are estimated to be 6 kg and 5 W, respectively. The package is proposed for a polar orbiter with a lifetime matching two Saturn seasons.

Aslam, S.↗
NASA NTRS2013

From Napkin to Orbit in 9 Months; The TechEdSat Spacecraft Mission

The TechEdSat spacecraft mission saw one of the fastest turn around times for concept through launch of a CubeSat. On 26 October 2011, John Hines sketched on a brown paper napkin the outline for which components would be in this 1U CubeSat, and how they would be stacked; 269 days later that spacecraft launched from Tanegashima Space Center aboard the HTV-3 ISS resupply mission, with a total development time of only eight months. TechEdSat was among the first of five CubeSats deployed from the ISS. The goals of the TechEdSat mission were to explore the use of the Space Plug-n-Play Architecture (SPA) in a CubeSat, and to evaluate Commercial Off The Shelf (COTS) space-to-space communication solutions. TechEdSat featured an array of processors from ÅAC Microtec including four NanoRTU's and the RTULite main processor, all communicating using the SPA-1 protocol. TechEdSat featured two primary payloads: an Iridium 9602 Modem, and a Quake Global Q1000 OrbComm modem. After a successful deployment on 4 October 2012 from the ISS, over 2000 packets of 122 bytes each (250 kB total) were received in the first four months of the mission. In this paper we discuss the challenges to rapid CubeSat development, the experience of having a CubeSat approved for deployment from the ISS, the ongoing results of the mission and lessons learned.

CUBESAT↗
NASA NTRS2018

Measurements of Parachute Dynamics in the World's Largest Wind Tunnel by Stereo Photogrammetry

Between 2012 and 2017, parachutes for four NASA Projects were tested in the 80- by 120-Ft test section of the National Full-Scale Aerodynamic Complex (NFAC) at NASA Ames Research Center. These projects were: (1) Low-Density Supersonic Decelerator (LDSD); (2) Capsule Parachute Assembly System (CPAS, for Orion); (3) Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight, a Mars mission); and (4) Mars 2020. In all tests stereo photogrammetry was used to measure time-dependent positions of features on the canopies. For the LDSD and CPAS tests, where the purpose was to study the trade-off between stability and drag of different parachute designs, the pendulum motion of the canopies about the riser attachment point was measured by calibrated cameras in the diffuser. The CPAS test also included static measurements where the inflated parachutes were pulled to the side by a system of tethers. The Insight tests were structural qualification tests where each canopy was packed in a bag and launched from a mortar. Cameras in the diffuser measured the trajectory of the bag and the stripping of the bag from the canopy. The Mars 2020 test was a workmanship verification test where the canopies were either launched from a mortar or deployed from a sleeve stretched along the tunnel axis. The deployments were recorded from many directions by thirteen high-speed cameras distributed in the diffuser and test section. Photogrammetry was not planned; however, after a tunnel-related accident ended the test prematurely, photogrammetric measurements were bootstrapped from the images to support the accident investigations. This paper describes how the photogrammetry measurements were made in each test and presents typical results.

Schairer, Edward T.↗
NASA NTRSDate not supplied

GASP Advancements With Symbolic Computations, Optimization, and Decoupled Numerical Methods

NASA is exploring advancements in hybrid-electric propulsion concepts for aircraft design. A new analysis capability has been deployed at NASA’s Ames Research Center using a new mathematical modeling framework in Python that leverages symbolic representation of mathematical expressions, optimization-based problem formulations, and standalone numerical methods. This capability, called Gascon, has been verified against NASA’s General Aviation Synthesis Program (GASP) results for several vehicles that exercise the analysis capability for a variety of aircraft classes and engine models, including both turbofans and turboprops. We believe this capability will set the stage for more rapid development of novel aircraft models with more flexible design assessments using optimization, and more traceable analysis for reproducibility. Additionally, a novel Pareto optimization-based design space exploration that shows the trade between range flown and fuel burn by manipulating the thrust split during cruise for a true parallel hybrid aircraft was developed by leveraging the unique features of Gascon.

aircraft design↗
NASA NTRSDate not supplied

xPLSS Structural Backplate Design, Manufacture, and Test Overview

NASA Johnson Space Center (JSC) has been developing and building a new detailed design of the Exploration Extravehicular Mobility Unit (xEMU) space suit to support future International Space Station (ISS) and Lunar Artemis missions. The Exploration Portable Life Support System (xPLSS) of the xEMU contains some clever new technologies to meet the requirements to provide Extra Vehicular Activity (EVA) capability on the ISS and the Moon. The suit must interface with and fit through ports and airlocks of at least three vehicles: ISS, Human Landing System (HLS), and Gateway. The first partial xPLSS experimental flight unit called SWME EXPRESS Rack Flight Experiment (SERFE) that was a rack-deployed thermal control system payload on the ISS for two years (2020-2022). The first complete assembly of the xEMU was built as a Design Verification Test (DVT) unit (2022); similar to but more extensive than an Engineering Development Unit (EDU). The xPLSS Backplate serves not only as the structural backbone of the xPLSS and SERFE systems but also contains innovative design features to reduce the: mass, complexity, parts count, number ofseals (and therefore leak potential), and outer dimensions of the entire assembly. This paper provides an overview of these new design features, manufacturing processes, system interfaces, and SERFE/DVT test results of the Backplate as part of the xPLSS/xEMU.

xPLSS↗
NASA NTRS2014

Extravehicular Activity Asteroid Exploration and Sample Collection Capability

NASA's Asteroid Redirect Crewed Mission (ARCM) is challenged with primary mission objectives of demonstrating deep space Extravehicular Activity (EVA) and tools, and obtaining asteroid samples to return to Earth for further study. Although the Modified Advanced Crew Escape Suit (MACES) is used for the EVAs, it has limited mobility which increases fatigue and decreases the crews' capability to perform EVA tasks. Furthermore, previous Shuttle and International Space Station (ISS) spacewalks have benefited from EVA interfaces which have been designed and manufactured on Earth. Rigid structurally mounted handrails, and tools with customized interfaces and restraints optimize EVA performance. For ARCM, some vehicle interfaces and tools can leverage heritage designs and experience. However, when the crew ventures onto an asteroid capture bag to explore the asteroid and collect rock samples, EVA complexity increases due to the uncertainty of the asteroid properties. The variability of rock size, shape and composition, as well as bunching of the fabric bag will complicate EVA translation, tool restraint and body stabilization. The unknown asteroid hardness and brittleness will complicate tool use. The rock surface will introduce added safety concerns for cut gloves and debris control. Feasible solutions to meet ARCM EVA objectives were identified using experience gained during Apollo, Shuttle, and ISS EVAs, terrestrial mountaineering practices, NASA Extreme Environment Mission Operations (NEEMO) 16 mission, and during Neutral Buoyancy Laboratory testing in the MACES suit. The proposed concept utilizes expandable booms and integrated features of the asteroid capture bag to position and restrain the crew at the asteroid worksite. These methods enable the capability to perform both finesse, and high load tasks necessary to collect samples for scientific characterization of the asteroid. This paper will explore the design trade space and options that were examined for EVA, the overall concept for the EVAs including translation paths and body restraint methods, potential tools used to extract the samples, design implications for the Asteroid Redirect Vehicle (ARV) for EVA, the results of early development testing of potential EVA tasks, and extensibility of the EVA architecture to NASA's exploration missions.

Scoville, Zebulon↗
NASA NTRS1993

Toward an Autonomous Feature-based Pointing System for Planetary Missions

Although the analytical groundwork for understanding two-dimensional object images and various aspects of computer vision has been laid, we have not yet applied these concepts to automating the process of obtaining science images during space exploration missions. Our current approach in specifying pointing-command sequences relies heavily on target predicts, based on predicted target and spacecraft ephemerides, that propagate the target position as a function of time during pointing operations.

Computer↗
NASA NTRS2008

Logistics Modeling for Lunar Exploration Systems

The extensive logistics required to support extended crewed operations in space make effective modeling of logistics requirements and deployment critical to predicting the behavior of human lunar exploration systems. This paper discusses the software that has been developed as part of the Campaign Manifest Analysis Tool in support of strategic analysis activities under the Constellation Architecture Team - Lunar. The described logistics module enables definition of logistics requirements across multiple surface locations and allows for the transfer of logistics between those locations. A key feature of the module is the loading algorithm that is used to efficiently load logistics by type into carriers and then onto landers. Attention is given to the capabilities and limitations of this loading algorithm, particularly with regard to surface transfers. These capabilities are described within the context of the object-oriented software implementation, with details provided on the applicability of using this approach to model other human exploration scenarios. Some challenges of incorporating probabilistics into this type of logistics analysis model are discussed at a high level.

Andraschko, Mark R.↗
NASA NTRS1985

Gamma-ray burst variability above 4 MeV

The relationship between the hard X-ray and gamma ray emissions during four bursts using the anti-coincidence shields of the High Energy Astronomy Observatory 3 (HEAO 3) Gamma Ray Spectrometer is explored. Recent observations of gamma ray bursts by the Solar Maximum Mission Gamma Ray Spectrometer (GRS) have shown that high energy emission above 1 MeV is a common and energetically important feature (Matz et al. 1985). Time histories of four gamma ray bursts in 3 energy bands ( keV, around 511 keV, and 4 MeV) with 10.24 a resolution show that the 4 MeV flux is only weakly coupled to the spectrum below approximately 600 keV.

Schwartz, R. A.↗
NASA NTRS1996

Global, Collisional Model of High-Energy Photoelectrons

A previously-developed colissional, interhemispheric flux tube model for photoelectrons (PE) has been extended to three dimensions by including transport due to vector E x vector B and magnetic gradient-curvature drifts. Using this model, initial calculations of the high-energy (greater then 50 eV) PE distribution as a function of time, energy, pitch angle, and spatial location in the equatorial plane, are reported for conditions of low geomagnetic activity. To explore both the dynamic and steady behaviors of the model, the simulation starts with the abrupt onset of photoelectron excitation, and is followed to steady state conditions. The results illustrate several features of the interaction of photoelectrons with typical magnetospheric plasmas and fields, including collisional diffusion of photoelectrons in pitch angle with flux tube filling, diurnal intensity and pitch angle asymmetries introduced by directional sunlight, and energization of the photoelectron distribution in the evening sector. Cross-field drift is shown to have a long time scale, taking 12 to 24 hours to reach a steady state distribution. Future applications of the model are briefly outlined.

Khazanov, G. V.↗
NASA NTRS2001

Road Extraction from AVIRIS Using Spectral Mixture and Q-Tree Filter Techniques

Accurate road location and condition information are of primary importance in road infrastructure management. Additionally, spatially accurate and up-to-date road networks are essential in ambulance and rescue dispatch in emergency situations. However, accurate road infrastructure databases do not exist for vast areas, particularly in areas with rapid expansion. Currently, the US Department of Transportation (USDOT) extends great effort in field Global Positioning System (GPS) mapping and condition assessment to meet these informational needs. This methodology, though effective, is both time-consuming and costly, because every road within a DOT's jurisdiction must be field-visited to obtain accurate information. Therefore, the USDOT is interested in identifying new technologies that could help meet road infrastructure informational needs more effectively. Remote sensing provides one means by which large areas may be mapped with a high standard of accuracy and is a technology with great potential in infrastructure mapping. The goal of our research is to develop accurate road extraction techniques using high spatial resolution, fine spectral resolution imagery. Additionally, our research will explore the use of hyperspectral data in assessing road quality. Finally, this research aims to define the spatial and spectral requirements for remote sensing data to be used successfully for road feature extraction and road quality mapping. Our findings will facilitate the USDOT in assessing remote sensing as a new resource in infrastructure studies.

Gardner, Margaret E.↗
NASA NTRS2007

From ESAS to Ares: A Chronology

This viewgraph presentation reviews the decision making that led to the choice of the Ares launch vehicle. There are charts that show comparisons of the features of the ESAS launch vehicles. There is discussion of the rationale of the choice of using a Evolved Expendable Launch Vehicle (EELV) as the launch vehicle for the future Crew Exploration Vehicle.

Cook, Steven A.↗
NASA NTRS2012

Bringing You the Moon: Lunar Education Efforts of the Center for Lunar Science and Education

The Center for Lunar Science and Exploration (CLSE), a collaboration between the Lunar and Planetary Institute and NASA's Johnson Space Center, is one of seven member teams of the NASA Lunar Science Institute. In addition to research and exploration activities, the CLSE team is deeply invested in education and public outreach. Overarching goals of CLSE education are to strengthen the future science workforce, attract and retain students in STEM disciplines, and develop advocates for lunar exploration. The team's efforts have resulted in a variety of programs and products, including the creation of a variety of Lunar Traveling Exhibits and the High School Lunar Research Project, featured at http://www.lpi.usra.edu/nlsi/education/.

Shaner, A. J.↗
NASA NTRS2011

Enabling Future Robotic Missions with Multicore Processors

Recent commercial developments in multicore processors (e.g. Tilera, Clearspeed, HyperX) have provided an option for high performance embedded computing that rivals the performance attainable with FPGA-based reconfigurable computing architectures. Furthermore, these processors offer more straightforward and streamlined application development by allowing the use of conventional programming languages and software tools in lieu of hardware design languages such as VHDL and Verilog. With these advantages, multicore processors can significantly enhance the capabilities of future robotic space missions. This paper will discuss these benefits, along with onboard processing applications where multicore processing can offer advantages over existing or competing approaches. This paper will also discuss the key artchitecural features of current commercial multicore processors. In comparison to the current art, the features and advancements necessary for spaceflight multicore processors will be identified. These include power reduction, radiation hardening, inherent fault tolerance, and support for common spacecraft bus interfaces. Lastly, this paper will explore how multicore processors might evolve with advances in electronics technology and how avionics architectures might evolve once multicore processors are inserted into NASA robotic spacecraft.

multi-core processor↗
NASA NTRS2012

NASA-NIAC 2001 Phase I Research Grant on Aneutronic Fusion Spacecraft Architecture

This study was developed because the recognized need of defining of a new spacecraft architecture suitable for aneutronic fusion and featuring game-changing space travel capabilities. The core of this architecture is the definition of a new kind of fusion-based space propulsion system. This research is not about exploring a new fusion energy concept, it actually assumes the availability of an aneutronic fusion energy reactor. The focus is on providing the best (most efficient) utilization of fusion energy for propulsion purposes. The rationale is that without a proper architecture design even the utilization of a fusion reactor as a prime energy source for spacecraft propulsion is not going to provide the required performances for achieving a substantial change of current space travel capabilities.

aneutronic↗
NASA NTRS2025

Laminae as Structural Biosignatures in NASA’s Life Detection Knowledge Base

Laminae are millimeter-scale features in rocks created by physiochemical processes that can be influenced by the presence and activities of communities of organisms that occur as biofilms and microbial mats. The structure and composition of laminae reflect the processes involved in their formation and can be preserved in the rock record over geologic time, however diagenetic and metamorphic alteration can lead to the loss of primary information and confusion over the interpretation of their origins. As potential records of ancient life, laminae can preserve evidence of microbial activity over billions of years of Earth’s history. On planetary bodies beyond Earth, laminae in sedimentary rocks are the most common sedimentary structure and represent significant features of interest that can record habitable conditions (e.g., the presence of liquid water) at the time of their formation. Here we review the significance of laminae as targets for astrobiological exploration. We discuss common mechanisms by which laminae form in natural environments on Earth, present arguments and evidence for laminae as biosignatures, and describe how such information is incorporated into the NASA Life Detection Knowledge Base.

Astrobiology↗
NASA NTRS2004

Teleoperation from Mars Orbit: A proposal for Human Exploration

For a human expedition to Mars, a case can be made that the best strategy for initial exploration is not to actually land the humans on Mars, but to put the humans into Mars orbit and operate on the surface by the technology of teleoperation. This will provide the results of human exploration, but at greatly reduced risk and cost. Teleoperation of Mars surface robots from a Mars-orbital habitat will operation near real time operation with minimum time delay, giving a virtual presence on the surface. By use of teleoperation, it is possible to vastly simplify the surface exploration mission. We now have no need to develop a human-rated Mars Lander and Mars Ascent Vehicle, and we can send geologists & biologists on the mission; not VTOL pilots. It is a cheaper, simpler, and safer way to explore, and hence it will be a faster way to explore. It has the excitement of being there, at a fraction of the price. Tele-exploration from Mars orbit also allows human (virtual) presence at a wide variety of locations. With an orbital base controlling surface telerobotics, human explorers are not stuck with one base location, but can explore all over Mars. They can explore the polar caps and also near-equatorial canyon regions, from the same orbiting base. This frees the mission from landing site constraints. With no need to select a "grab bag" site that contains a large number of geologically diverse features at or near a single location; it is now possible go to all the best sites-- paleolake sites, river beds, volcanic calderas, lava tube sites, layered terrain, canyons, possible shoreline features, the North and South poles. A near-polar inclination 24-hr 39-minute period Mars orbit, for example, will put the orbital station in line-of-sight of a given region for about 8 hours per day-- one teleoperation shift. Since present day life could exist on Mars, planetary protection is also needed to preserve the (possible) fragile Mars biosphere from competition from ferocious Earth life. Isolated biospheres on Earth have been devastated when they have been exposed to alien life forms introduced-accidentally or deliberately-- from another continent. If there is life on Mars, we will wish to protect it from having to compete with introduced Earth biota. Reverse planetary protection-protecting the Earth biosphere from exposure to Mars microorganisms-is also an important consideration. Exploring from orbit will reduce biological risk by keeping humans from exposure to possible Mars microbes. A telerobotic mission will need no quarantine on return to Earth, and avoids the difficult human question of how to isolate Mars mission astronauts infected by Martian microorganisms.

Landis, Geoffrey A.↗
NASA NTRS1983

Geologic exploration: The contribution of LANDSAT-4 thematic mapper data

The major advantages of the TM data over that of MSS systems are increased spatial resolution and a greater number of narrow, strategically placed spectral bands. The 30 meter pixel size permits finer definition of ground features and improves reliability of the photointerpretation of geologic structure. The value of the spatial data increases relative to the value of the spectral data as soil and vegetation cover increase. In arid areas with good exposure, it is possible with careful digital processing and some inventive color compositing to produce enough spectral differentiation of rock types and thereby produce facsimiles of standard geologic maps with a minimum of field work or reference to existing maps. Hue-saturation value images are compared with geological maps of Death Valley, California, the Big Horn/Wind River Basin of Wyoming, the area around Cement, Oklahoma, and Detroit. False color composites of the Ontario region are also examined.

Everett, J. R.↗