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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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS2000

The Small Aircraft Transportation System for America: A Case in Public Infrastructure Change

The National Aeronautics and Space Administration (NASA), U.S. Department of Transportation, Federal Aviation Administration, industry stakeholders, and academia, have joined forces to pursue the NASA National General Aviation Roadmap leading to a Small Aircraft Transportation System (SATS). This strategic undertaking has a 25-year goal to bring next-generation technologies and improve travel between remote communities and transportation centers in urban areas by utilizing the nation's 5,400 public-use general aviation airports. To facilitate this initiative, a comprehensive upgrade of public infrastructure must be planned, coordinated, and implemented within the framework of the national air transportation system. The Nebraska NASA EPSCoR Program has proposed to deliver research support in key public infrastructure areas in coordination with the General Aviation Program Office at the NASA Langley Research Center. Ultimately, SATS may permit tripling aviation system throughput capacity by tapping the underutilized general aviation facilities to achieve the national goal of doorstep-to-destination travel at four times the speed of highways for the nation's suburban, rural, and remote communities.

Bowen, Brent D.↗
NASA NTRS2001

A Scalable Analysis Toolkit

The Scalable Analysis Toolkit (SAT) project aimed to demonstrate that it is feasible and useful to statically detect software bugs in very large systems. The technical focus of the project was on a relatively new class of constraint-based techniques for analysis software, where the desired facts about programs (e.g., the presence of a particular bug) are phrased as constraint problems to be solved. At the beginning of this project, the most successful forms of formal software analysis were limited forms of automatic theorem proving (as exemplified by the analyses used in language type systems and optimizing compilers), semi-automatic theorem proving for full verification, and model checking. With a few notable exceptions these approaches had not been demonstrated to scale to software systems of even 50,000 lines of code. Realistic approaches to large-scale software analysis cannot hope to make every conceivable formal method scale. Thus, the SAT approach is to mix different methods in one application by using coarse and fast but still adequate methods at the largest scales, and reserving the use of more precise but also more expensive methods at smaller scales for critical aspects (that is, aspects critical to the analysis problem under consideration) of a software system. The principled method proposed for combining a heterogeneous collection of formal systems with different scalability characteristics is mixed constraints. This idea had been used previously in small-scale applications with encouraging results: using mostly coarse methods and narrowly targeted precise methods, useful information (meaning the discovery of bugs in real programs) was obtained with excellent scalability.

Aiken, Alexander↗
NASA NTRS2001

Integrated Power Source Grant

Traditional spacecraft power systems incorporate a solar array energy source, an energy storage element (battery), and battery charge control and bus voltage regulation electronics to provide continuous electrical power for spacecraft systems and instruments. Dedicated power conditioning components provide limited fault isolation between systems and instruments, while a centralized power-switching unit provides spacecraft load control. Battery undervoltage conditions are detected by the spacecraft processor, which removes fault conditions and non-critical loads before permanent battery damage can occur. Cost effective operation of a micro-sat constellation requires a fault tolerant spacecraft architecture that minimizes on-orbit operational costs by permitting autonomous reconfiguration in response to unexpected fault conditions. A new micro-sat power system architecture that enhances spacecraft fault tolerance and improves power system survivability by continuously managing the battery charge and discharge processes on a cell-by-cell basis has been developed. This architecture is based on the Integrated Power Source (US patent 5644207), which integrates dual junction solar cells, Lithium Ion battery cells, and processor based charge control electronics into a structural panel that can be deployed or used to form a portion of the outer shell of a micro-spacecraft. The first generation Integrated Power Source is configured as a one inch thick panel in which prismatic Lithium Ion battery cells are arranged in a 3x7 matrix (26VDC) and a 3x1 matrix (3.7VDC) to provide the required output voltages and load currents. A multi-layer structure holds the battery cells, as well as the thermal insulators that are necessary to protect the Lithium Ion battery cells from the extreme temperatures of the solar cell layer. Independent thermal radiators, located on the back of the panel, are dedicated to the solar cell array, the electronics, and the battery cell array. In deployed panel applications, these radiators maintain the battery cells in an appropriate operational temperature range.

Source record↗
NASA NTRS2005

Flight Experiment Investigation of General Aviation Self-Separation and Sequencing Tasks

A new flight operations concept called Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) was developed to increase capacity during Instrument Meteorological Conditions (IMC) at non-towered, non-radar airports by enabling concurrent operations of multiple aircraft. One aspect of this concept involves having pilots safely self-separate from other aircraft during approaches into these airports using appropriate SATS HVO procedures. A flight experiment was conducted to determine if instrument-rated general aviation (GA) pilots could self-separate and sequence their ownship aircraft, while following a simulated aircraft, into a non-towered, non-radar airport during simulated IMC. Six GA pilots' workload levels and abilities to perform self-separation and sequencing procedures while flying a global positioning system (GPS) instrument approach procedure were examined. The results showed that the evaluation pilots maintained at least the minimum specified separation between their ownship aircraft and simulated traffic and maintained their assigned landing sequence 100-percent of the time. Neither flight path deviations nor subjective workload assessments were negatively impacted by the additional tasks of self-separating and sequencing during these instrument approaches.

Murdoch, Jennifer L.↗
NASA NTRS2005

Small Aircraft Transportation System, Higher Volume Operations Concept: Off-Nominal Operations

This document expands the Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept to include off-nominal conditions. The general philosophy underlying the HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). During periods of poor weather, a block of airspace would be established around designated non-towered, non-radar airports. Aircraft flying enroute to a SATS airport would be on a standard instrument flight rules flight clearance with Air Traffic Control providing separation services. Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Previous work developed the procedures for normal HVO operations. This document provides details for off-nominal and emergency procedures for situations that could be expected to occur in a future SCA.

Abbott, Terence S.↗
NASA NTRS2006

Point-to-Point! Validation of the Small Aircraft Transportation System Higher Volume Operations Concept

Described is the research process that NASA researchers used to validate the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept. The four phase building-block validation and verification process included multiple elements ranging from formal analysis of HVO procedures to flight test, to full-system architecture prototype that was successfully shown to the public at the June 2005 SATS Technical Demonstration in Danville, VA. Presented are significant results of each of the four research phases that extend early results presented at ICAS 2004. HVO study results have been incorporated into the development of the Next Generation Air Transportation System (NGATS) vision and offer a validated concept to provide a significant portion of the 3X capacity improvement sought after in the United States National Airspace System (NAS).

Williams, Daniel M.↗
NASA NTRS2006

Monte Carlo Analysis of Airport Throughput and Traffic Delays Using Self Separation Procedures

This paper presents the results of three simulation studies of throughput and delay times of arrival and departure operations performed at non-towered, non-radar airports using self-separation procedures. The studies were conducted as part of the validation process of the Small Aircraft Transportation Systems Higher Volume Operations (SATS HVO) concept and include an analysis of the predicted airport capacity using with different traffic conditions and system constraints under increasing levels of demand. Results show that SATS HVO procedures can dramatically increase capacity at non-towered, non-radar airports and that the concept offers the potential for increasing capacity of the overall air transportation system.

Consiglio, Maria C.↗
NASA NTRS2007

High Accuracy 3D Processing of Satellite Imagery

Automatic DSM/DTM generation reproduces not only general features, but also detailed features of the terrain relief. Height accuracy of around 1 pixel in cooperative terrain. RMSE values of 1.3-1.5 m (1.0-2.0 pixels) for IKONOS and RMSE values of 2.9-4.6 m (0.5-1.0 pixels) for SPOT5 HRS. For 3D city modeling, the manual and semi-automatic feature extraction capability of SAT-PP provides a good basis. The tools of SAT-PP allowed the stereo-measurements of points on the roofs in order to generate a 3D city model with CCM The results show that building models with main roof structures can be successfully extracted by HRSI. As expected, with Quickbird more details are visible.

Gruen, A.↗
NASA NTRS2007

Space Technology 5 - A Successful Micro-Satellite Constellation Mission

The Space Technology 5 (ST5) constellation of three micro-satellites was launched March 22, 2006. During the three-month flight demonstration phase, the ST5 team validated key technologies that will make future low-cost micro-sat constellations possible, demonstrated operability concepts for future micro-sat science constellation missions, and demonstrated the utility of a micro-satellite constellation to perform research-quality science. The ST5 mission was successfully completed in June 2006, demonstrating high-quality science and technology validation results.

Carlisle, Candace↗
NASA NTRS2005

Incorporating Data Link Features into a Multi-Function Display to Support Self-Separation and Spacing Tasks for General Aviation Pilots

One objective of the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) project is to increase the capacity and utilization of small non-towered, non-radar equipped airports by transferring traffic management activities to an automated Airport Management Module (AMM) and separation responsibilities to general aviation (GA) pilots. Implementation of this concept required the development of a research Multi-Function Display (MFD) to support the interactive communications between pilots and the AMM. The interface also had to accommodate traffic awareness, self-separation, and spacing tasks through dynamic messaging and symbology for flight path conformance and conflict detection and alerting (CDA). The display served as the mechanism to support the examination of the viability of executing instrument operations designed for SATS designated airports. Results of simulation and flight experiments conducted at the National Aeronautics and Space Administration's (NASA) Langley Research Center indicate that the concept, as facilitated by the research MFD, did not increase pilots subjective workload levels or reduce their situation awareness (SA). Post-test usability assessments revealed that pilots preferred using the enhanced MFD to execute flight procedures, reporting improved SA over conventional instrument flight rules (IFR) procedures.

Adams, Catherine A.↗
NASA NTRS2005

Hybrid Verification of an Air Traffic Operational Concept

A concept of operations for air traffic management consists of a set of flight rules and procedures aimed to keep aircraft safely separated. This paper reports on the formal verification of separation properties of the NASA's Small Aircraft Transportation System, Higher Volume Operations (SATS HVO) concept for non-towered, non-radar airports. Based on a geometric description of the SATS HVO air space, we derive analytical formulas to compute spacing requirements on nominal approaches. Then, we model the operational concept by a hybrid non-deterministic asynchronous state transition system. Using an explicit state exploration technique, we show that the spacing requirements are always satisfied on nominal approaches. All the mathematical development presented in this paper has been formally verified in the Prototype Verification System (PVS). Keywords. Formal verification, hybrid systems, air traffic management, theorem proving

Munoz, Cesar A.↗
NASA NTRS2009

The 50 Constellation Priority Sites

The Constellation program (CxP) has developed a list of 50 sites of interest on the Moon which will be targeted by the LRO narrow angle camera. The list has also been provided to the M~ team to supplement their targeting list. This list does not represent a "site selection" process; rather the goal was to find "representative" sites and terrains to understand the range of possible surface conditions for human lunar exploration to aid engineering design and operational planning. The list compilers leveraged heavily on past site selection work (e.g. Geoscience and a Lunar Base Workshop - 1988, Site Selection Strategy for a Lunar Outpost - 1990, Exploration Systems Architecture Study (ESAS) - 2005). Considerations included scientific, resource utilization, and operational merits, and a desire to span lunar terrain types. The targets have been organized into two "tiers" of 25 sites each to provide a relative priority ranking in the event of mutual interference. A LEAG SAT (special action team) was established to validate and recommend modifications to the list. This SAT was chaired by Dr. Paul Lucey. They provided their final results to CxP in May. Dr. Wendell Mendell will organize an on-going analysis of the data as they come down to ensure data quality and determine if and when a site has sufficient data to be retired from the list. The list was compiled using the best available data, however, it is understood that with the flood of new lunar data, minor modifications or adjustments may be required.

Noble, S.↗
NASA NTRS2013

Space Station Integrated Kinetic Launcher for Orbital Payload Systems (SSIKLOPS) - Cyclops

Access to space for satellites in the 50-100 kg class is a challenge for the small satellite community. Rideshare opportunities are limited and costly, and the small sat must adhere to the primary payloads schedule and launch needs. Launching as an auxiliary payload on an Expendable Launch Vehicle presents many technical, environmental, and logistical challenges to the small satellite community. To assist the community in mitigating these challenges and in order to provide the community with greater access to space for 50-100 kg satellites, the NASA International Space Station (ISS) and Engineering communities in collaboration with the Department of Defense (DOD) Space Test Program (STP) is developing a dedicated 50-100 kg class ISS small satellite deployment system. The system, known as Cyclops, will utilize NASA's ISS resupply vehicles to launch small sats to the ISS in a controlled pressurized environment in soft stow bags. The satellites will then be processed through the ISS pressurized environment by the astronaut crew allowing satellite system diagnostics prior to orbit insertion. Orbit insertion is achieved through use of the Japan Aerospace Exploration Agency's Experiment Module Robotic Airlock (JEM Airlock) and one of the ISS Robotic Arms. Cyclops' initial satellite deployment demonstration of DOD STP's SpinSat and UT/TAMU's Lonestar satellites will be toward the end of 2013 or beginning of 2014. Cyclops will be housed on-board the ISS and used throughout its lifetime. The anatomy of Cyclops, its concept of operations for satellite deployment, and its satellite interfaces and requirements will be addressed further in this paper.

Smith, James P.↗
NASA NTRS2014

Small, Low Cost, Launch Capability Development

A recent explosion in nano-sat, small-sat, and university class payloads has been driven by low cost electronics and sensors, wide component availability, as well as low cost, miniature computational capability and open source code. Increasing numbers of these very small spacecraft are being launched as secondary payloads, dramatically decreasing costs, and allowing greater access to operations and experimentation using actual space flight systems. While manifesting as a secondary payload provides inexpensive rides to orbit, these arrangements also have certain limitations. Small, secondary payloads are typically included with very limited payload accommodations, supported on a non interference basis (to the prime payload), and are delivered to orbital conditions driven by the primary launch customer. Integration of propulsion systems or other hazardous capabilities will further complicate secondary launch arrangements, and accommodation requirements. The National Aeronautics and Space Administration's Marshall Space Flight Center has begun work on the development of small, low cost launch system concepts that could provide dedicated, affordable launch alternatives to small, high risk university type payloads and spacecraft. These efforts include development of small propulsion systems and highly optimized structural efficiency, utilizing modern advanced manufacturing techniques. This paper outlines the plans and accomplishments of these efforts and investigates opportunities for truly revolutionary reductions in launch and operations costs. Both evolution of existing sounding rocket systems to orbital delivery, and the development of clean sheet, optimized small launch systems are addressed.

Brown, Thomas↗
NASA NTRS2014

Enabling Dedicated, Affordable Space Access Through Aggressive Technology Maturation

A recent explosion in nano-sat, small-sat, and university class payloads has been driven by low cost electronics and sensors, wide component availability, as well as low cost, miniature computational capability and open source code. Increasing numbers of these very small spacecraft are being launched as secondary payloads, dramatically decreasing costs, and allowing greater access to operations and experimentation using actual space flight systems. While manifesting as a secondary payload provides inexpensive rides to orbit, these arrangements also have certain limitations. Small, secondary payloads are typically included with very limited payload accommodations, supported on a non interference basis (to the prime payload), and are delivered to orbital conditions driven by the primary launch customer. Integration of propulsion systems or other hazardous capabilities will further complicate secondary launch arrangements, and accommodation requirements. The National Aeronautics and Space Administration's Marshall Space Flight Center has begun work on the development of small, low cost launch system concepts that could provide dedicated, affordable launch alternatives to small, risk tolerant university type payloads and spacecraft. These efforts include development of small propulsion systems and highly optimized structural efficiency, utilizing modern advanced manufacturing techniques. This paper outlines the plans and accomplishments of these efforts and investigates opportunities for truly revolutionary reductions in launch and operations costs. Both evolution of existing sounding rocket systems to orbital delivery, and the development of clean sheet, optimized small launch systems are addressed. A launch vehicle at the scale and price point which allows developers to take reasonable risks with new propulsion and avionics hardware solutions does not exist today. Establishing this service provides a ride through the proverbial "valley of death" that lies between demonstration in laboratory and flight environments. This effort will provide the framework to mature both on-orbit and earth-to-orbit avionics and propulsion technologies while also providing dedicated, affordable access to LEO for cubesat class payloads.

Jones, Jonathan↗
NASA NTRS2013

A Technology Development Roadmap for a Near-Term Probe-Class X-ray Astrophysics Mission

This document presents a roadmap, including proposed budget and schedule, for maturing the instrumentation needed for an X-ray astrophysics Probe-class mission. The Physics of the Cosmos (PCOS) Program Office was directed to create this roadmap following the December 2012 NASA Astrophysics Implementation Plan (AIP). Definition of this mission is called for in the AIP, with the possibility of selection in 2015 for a start in 2017. The overall mission capabilities and instrument performance requirements were defined in the 2010 Astronomy and Astrophysics Decadal Survey report, New Worlds, New Horizons in Astronomy and Astrophysics (NWNH), in connection with the highly ranked International X-ray Observatory (IXO). In NWNH, recommendations were provided regarding the size of, and instrumentation needed by, the next large X-ray observatory. Specifically, the key instrumental capability would be an X-ray calorimeter spectrometer at the focus of a large mirror with angular resolution of 10 arc seconds (arcsec) or better. If possible, a grating spectrometer should also be incorporated into the instrument complement. In response to these recommendations, four instrumentation technologies are included in this roadmap. Three of these are critical for an X-ray mission designed to address NWNH questions: segmented X-ray mirrors, transition edge sensor calorimeters, and gratings. Two approaches are described for gratings, which represent the least mature technology and thus most in need of a parallel path for risk reduction. Also, while current CCD detectors would likely meet the mission needs for grating spectrum readout, specific improvements are included as an additional approach for achieving the grating system effective area requirement. The technical steps needed for these technologies to attain technology readiness levels (TRL) of 5 and 6 are described, as well as desirable modest risk reduction steps beyond TRL-6. All of the technology development efforts are currently funded through the NASA Physics of the Cosmos (PCOS) Strategic Astrophysics Technology (SAT) program; some through the end of FY13, others though FY14. These technology needs are those identified as critical for a near-term mission and briefly described in the 2012 NASA X-ray Mission Concepts Study. This Technology Development Roadmap (TDR) provides a more complete description of each, updates the status, and describes the steps to mature them. For each technology, a roadmap is presented for attaining TRL-6 by 2020 at the latest, and 2018 for most. The funding required for each technology to attain TRL-5 and TRL-6 is presented and justified through a description of the steps needing completion. The total funding required for these technologies to reach TRL-6 is relatively modest, and is consistent with the planned PCOS SAT funding over the next several years. The approximate annual cost through 2018 is $8M. The total cost for all technologies to be matured is $62M (including funding already awarded for FY13 and FY14). This can be contrasted to the $180M recommended by NWNH for technology development for IXO, primarily for the maturation of the mirror technology. The technology described in Section 3 of this document is exclusively that needed for a near-term Probe-class mission, to start in 2017, or for a mission that can be recommended by the next Decadal survey committee for an immediate start. It is important to note that there are other critical X-ray instrumentation technologies under development that are less mature than the ones discussed here, but are essential for a major X-ray mission that might start in the late 2020s. These technologies, described briefly in Section 4, are more appropriately funded through the Astronomy and Physics Research and Analysis (APRA) program.

Development↗
NASA NTRS2014

Plasmonic Force Propulsion Revolutionizes Nano/Picosatellite Capability

This project investigated a new type of small spacecraft propulsion for attitude control, specifically proximity and precision pointing control. Plasmonic force propulsion uses solar light focused on deep-subwavelength nanostructures to excite strong optical forces that accelerate and expel nanoparticle propellant. The goal of the project was to assess the feasibility of plasmonic force propulsion for nano/pico-satellite applications by evaluating key mission parameters for a nano/pico-satellite using plasmonic force propulsion in a NASA-relevant mission context. We achieved this goal and objective by evaluating plasmonic force propulsion within a NASA mission that required attitude control and precision pointing of a small satellite. We numerically simulated plasmonic force fields with asymmetric/gradient geometry and relevant solar light constraints, predicted nanoparticle velocity, mass flow rate, and resulting propulsion performance (thrust, specific impulse), and evaluated spacecraft position control resolution and pointing precision. Additionally we compared the precision pointing capabilities of plasmonic propulsion, as well as the mass, volume, and power requirements, with other state-of-the-art control techniques, such as reaction wheels and colloid/electrospray electric propulsion. The results are very exciting. Plasmonic force propulsion can significantly enhance the state-of-the-art in small spacecraft position and attitude control by 1-2 orders of magnitude. This is most succinctly shown in the figure below, which compares proximity and attitude control of plasmonic force propulsion (PFP) with other state-of-the-art thruster systems (μCAT, VAT, electrospray). Additionally this figure also shows the proximity and attitude control required for different existing (James Webb Space Telescope, Hubble) and future (LISA and Stellar Imager) NASA missions. While some of these NASA missions are not small spacecraft missions, the requirements serve to illustrate the fact that more precise proximity and attitude control will be required for future NASA science missions. Stellar imager is a proposed NASA missions that requires an extremely high pointing precision of 0.1 milliarcseconds (2.7x10(exp -7) deg.) for an ultraviolet telescope that has over 200× the resolution of the Hubble Space Telescope, is able to take images showing details on the surfaces of other stars, consists of 20-30 small "mirror sats" flying in formation to produce a giant mirror, and requires each mirror-sat to be placed with nanometer precision and control its attitude with milliarcsecond precision.

Rovey, Joshua L.↗
NASA NTRS2014

Design, Development, Implementation, and On-Orbit Performance of the Dynamic Ionosphere CubeSat Experiment Mission

Funded by the NSF CubeSat and NASA ELaNa programs, the Dynamic Ionosphere CubeSat Experiment (DICE) mission consists of two 1.5U (1.5 Unit) CubeSats which were launched into an eccentric low Earth orbit on October 28, 2011. Each identical spacecraft carries two Langmuir probes to measure ionospheric in-situ plasma densities, electric field probes to measure in-situ DC and AC electric fields, and a science grade magnetometer to measure in-situ DC and AC magnetic fields. Given the tight integration of these multiple sensors with the CubeSat platforms, each of the DICE spacecraft is effectively a sensor-sat capable of comprehensive ionospheric diagnostics. The use of two identical sensor-sats at slightly different orbiting velocities in nearly identical orbits permits the deconvolution of spatial and temporal ambiguities in the observations of the ionosphere from a moving platform. In addition to demonstrating nanosat-based constellation science, the DICE mission is advancing a number of groundbreaking CubeSat technologies including miniaturized mechanisms and high-speed downlink communications.

DICE↗