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An approach to learning engineering design is discussed with particular attention given to the impact of the NASA/Universities Space Research Association (USRA) Advanced Design Program (ADP) on that process. Attention is also given to a teaching method stressing science discipline and creativity and various selected space related designs.
An automated structures assembly testbed developed by Langley Research Center to study the practical problems associated with the automated assembly of large space structures using robotic manipulators is described. Emphasis is placed on the requirements and features of system upgrades and their impact on system performance, flexibility, and reliability. The current research program is aimed at evolving the baseline assembly system into a flexible, robust, sensor-based system capable of assembling more complex truss-supported satellite systems. To achieve this objective, five system upgrades have been developed including a machine vision capability to eliminate taught robot arm positions; an on-board end-effector microprocessor to reduce communications; a second-generation end-effector to construct contoured trusses for antennas and install payloads; the installation of reflector-type panels on the truss to produce a complete and functional system, and an expert system to significantly reduce the amount of software code required for system operation and provide greater flexibility in implementing new features.
The results of a series of tests conducted at the NASA Langley Research Center to evaluate the behavior of an all-composite full-scale wing box are presented. The wing stub box is representative of a section of a commercial transport aircraft wing box and was designed and constructed by McDonnell Douglas Aerospace Company as part of the NASA Advanced Composites Technology (ACT) program. Tests were conducted with and without low-speed impact damage and repairs. The structure with nonvisible impact damage carried 140 percent of Design Limit Load prior to failure through an impact site.
The NASA Institute for Advanced Concepts (NIAC) was formed in 1998 to provide an independent source of advanced aeronautical and space concepts that could dramatically impact how NASA develops and conducts its missions. Until the program's termination in August 2007, NIAC provided an independent open forum, a high-level point of entry to NASA for an external community of innovators, and an external capability for analysis and definition of advanced aeronautics and space concepts to complement the advanced concept activities conducted within NASA. Throughout its 9-year existence, NIAC inspired an atmosphere for innovation that stretched the imagination and encouraged creativity. As requested by Congress, this volume reviews the effectiveness of NIAC and makes recommendations concerning the importance of such a program to NASA and to the nation as a whole, including the proper role of NASA and the federal government in fostering scientific innovation and creativity and in developing advanced concepts for future systems. Key findings and recommendations include that in order to achieve its mission, NASA must have, and is currently lacking, a mechanism to investigate visionary, far-reaching advanced concepts. Therefore, a NIAC-like entity should be reestablished to fill this gap.
Results are presented of a computational fluid dynamics (CFD) study done in support of Marshall Space Flight Center's (MSFC) sub-scale water flow experiments of the Hydrocarbon Boost (HCB) Oxidizer Turbopump (OTP) being developed by the Air Force Research Laboratory (AFRL) and Aerojet. A circumferential groove may be added to the pump to reduce synchronous cavitation and subsequent bearing loads at a minimal performance cost. However, the energy may reappear as high order cavitation (HOC) that spans a relatively large frequency range. Thus, HOC may have implications for the full-scale OTP inducer in terms of reduced structural margin at higher mode frequencies. Simulations using the LOCI/Stream CFD program were conducted in order to explore the fluid dynamical impact of the groove on the low-pressure inducer and kicker. It was found that the circumferential groove has minimal head performance impact, but causes back-flowing high-swirl fluid to interact with the nearly-axial incoming fluid just above the inducer blades. The high-shear interface between the fluids is Kelvin-Helmholtz unstable, resulting in trains of low pressure regions or 'pearls' forming near the upstream edge of the groove. When the static pressure in these regions becomes low enough and they get cut by the blade leading edge, HOC is thought to occur. Although further work is required, the numerical models indicate that HOC will occur in the runbox of the AFRL/Aerojet HCB OTP. Comparisons to the ongoing water flow experiments will be discussed, as well as possible designs that may mitigate HOC while continuing to reduce synchronous cavitation. December 2011 MSS/LPS/SPS Joint Subcommittee Meeting ABSTRACT SUBMITTAL FORM
Atmospheric particles including mineral dust, biomass burning smoke, pollution from carbonaceous aerosols and sulfates, sea salt, impact air quality and climate. The Aerosol Robotic Network (AERONET) program, established in the early 1990s, is a federation of ground-based remote sensing aerosol networks of Sun/sky radiometers distributed around the world, which provides a long-term, continuous and readily accessible public domain database of aerosol optical (e.g., aerosol optical depth) and microphysical (e.g., aerosol volume size distribution) properties for aerosol characterization, validation of satellite retrievals, and synergism with Earth science databases. Climatological aerosol properties will be presented at key worldwide locations exhibiting discrete dominant aerosol types. Further, AERONET's temporary mesoscale network campaign (e.g., UAE2, TIGERZ, DRAGON-USA.) results that attempt to quantify spatial and temporal variability of aerosol properties, establish validation of ground-based aerosol retrievals using aircraft profile measurements, and measure aerosol properties on compatible spatial scales with satellite retrievals and aerosol transport models allowing for more robust validation will be discussed.
A 2015 NASA Aeronautics Mission "Seedling" Proposal is described for a Severe-Environment UAV (SE-UAV) that can perform in-situ measurements in hazardous atmospheric conditions like lightning, volcanic ash and radiation. Specifically, this paper describes the design of a proof-of-concept vehicle and measurement system that can survive lightning attachment during flight operations into thunderstorms. Elements from three NASA centers draw together for the SE-UAV concept. 1) The NASA KSC Genesis UAV was developed in collaboration with the DARPA Nimbus program to measure electric field and X-rays present within thunderstorms. 2) A novel NASA LaRC fiber-optic sensor uses Faraday-effect polarization rotation to measure total lightning electric current on an air vehicle fuselage. 3) NASA AFRC's state-of-the-art Fiber Optics and Systems Integration Laboratory is envisioned to transition the Faraday system to a compact, light-weight, all-fiber design. The SE-UAV will provide in-flight lightning electric-current return stroke and recoil leader data, and serve as a platform for development of emerging sensors and new missions into hazardous environments. NASA's Aeronautics and Science Missions are interested in a capability to perform in-situ volcanic plume measurements and long-endurance UAV operations in various weather conditions. (Figure 1 shows an artist concept of a SE-UAV flying near a volcano.) This paper concludes with an overview of the NASA Aeronautics Strategic Vision, Programs, and how a SE-UAV is envisioned to impact them. The SE-UAV concept leverages high-value legacy research products into a new capability for NASA to fly a pathfinder UAV into hazardous conditions, and is presented in the SPIE DSS venue to explore teaming, collaboration and advocacy opportunities outside NASA.
Jim McBarron exhibits a wealth of knowledge gathered from more than 40 years of experience with NASA, EVA, and spacesuits. His biography, progression of work at NASA, impact on EVA and the U.S. spacesuit, and career accomplishments are of interest to many. Wright, from the JSC History Office, conducted a personal background interview with McBarron. This interview highlighted the influences and decision-making methods that impacted McBarron's technical and management contributions to the space program. Attendees gained insight on the external and internal NASA influences on career progression within the EVA and spacesuit, and the type of accomplishments and technical advances that committed individuals can make. He concluded the presentation with a question and answer period that included a brief discussion about close calls and Russian spacesuits.
Whether putting rovers on Mars or sustaining life in extreme conditions, NASA develops technologies to solve some of the most difficult challenges ever faced. Through its Technology Transfer Program, the agency makes the innovations behind space exploration available to industry, academia, and the general public. This paper describes the primary mechanisms through which NASA disseminates technology to solve real-life problems; illustrates recent program accomplishments; and provides examples of spinoff success stories currently impacting everyday life.
The Global Learning and Observations to Benefit the Environment (GLOBE) Program was announced on Earth Day 1994 and began on Earth Day 1995. Over the first 25 years of its operation, there have been more than 600 formal publications and 340 conference presentations about the program, in at least 15 languages. As the 25th anniversary of the program approached, we began a focused effort to find and characterize those publications in order to better understand GLOBE’s impact to date as well as its future potential. GLOBE was envisioned from the beginning as a science and education program, so GLOBE publications cover a wide range of topics across Earth system science as well as in education and evaluation topics. To characterize the collection, a large set of dimensions was first identified from the literature, across science and education. These include codes related to: motivation and conception of the research investigation, educator practices and training, education outcomes & demonstration that these outcomes were achieved, data and study scope, characteristics of the investigation or its findings. Application of these codes was first tested by three raters (the first three authors) on a subset of the publications, then refined to capture missing aspects. The full set of publications was then rated on the full set of criteria. As a second step, subsets of the collection with particularly in depth discussion of The GLOBE Program are now being analyzed in more detail. This poster will summarize various attributes of the GLOBE bibliography and identify areas of potential for further geoscience investigations.
Some of the Earth system data products such as those from NASA airborne and field investigations (a.k.a. campaigns), are highly heterogeneous and cross-disciplinary, making the data extremely challenging to manage. For example, airborne and field campaign measurements tend to be sporadic over a period of time, with large gaps. Data products generated are of various processing levels and utilized for a wide range of inter- and cross-disciplinary research and applications. Data and derived products have been historically stored in a variety of domain-specific standard (and some non-standard) formats and in various locations such as NASA Distributed Active Archive Centers (DAACs), NASA airborne science facilities, field archives, or even individual scientists’ computer hard drives. As a result, airborne and field campaign data products have often been managed and represented differently, making it onerous for data users to find, access, and utilize campaign data. Some difficulties in discovering and accessing the campaign data originate from the incomplete data product and contextual metadata that may contain details relevant to the campaign (e.g. campaign acronym and instrument deployment locations), but tend to lack other significant information needed to understand conditions surrounding the data. Such details can be burdensome to locate after the conclusion of a campaign. Utilizing consistent terminology, essential for improved discovery and reuse, is also challenging due to the variety of involved disciplines. To help address the aforementioned challenges faced by many repositories and data managers handling airborne and field data, this presentation will describe stewardship practices developed by the Airborne Data Management Group (ADMG) within the Interagency Implementation and Advanced Concepts Team (IMPACT) under the NASA’s Earth Science Data systems (ESDS) Program.
The EVA/Space Suit Development Office (ESSD) Systems Engineering and Integration (SE&I) team has utilized MBSE in multiple programs. After developing operational and architectural models, the MBSE framework was expanded to link the requirements space to the system models through functional analysis and interfaces definitions. By documenting all the connections within the technical baseline, ESSD experienced significant efficiency improvements in analysis and identification of change impacts. One of the biggest challenges presented to the MBSE structure was a program transition and restructuring effort, which was completed successfully in 4 months culminating in the approval of a new EVA Technical Baseline. During this time three requirements sets spanning multiple DRMs were streamlined into one NASA-owned Systems Requirement Document (SRD) that successfully identified requirements relevant to the current hardware development effort while remaining extensible to support future hardware developments. A capability-based hierarchy was established to provide a more flexible framework for future space suit development that can support multiple programs with minimal rework of basic EVA/Space Suit requirements. This MBSE approach was most recently applied for generation of an EMU Demonstrator technical baseline being developed for an ISS DTO. The relatively quick turnaround of operational concepts, architecture definition, and requirements for this new suit development has allowed us to test and evolve the MBSE process and framework in an extremely different setting while still offering extensibility and traceability throughout ESSD projects. The ESSD MBSE framework continues to be evolved in order to support integration of all products associated with the SE&I engine.
This paper describes the status of the current NASA programs that are aimed at providing new technology for aircraft designs that will improve both safety and utility while reducing the environmental impact of general aviation to acceptable levels. Safety related areas that are discussed include the full scale crash test program and the stall/spin research effort. Among the programs addressing increased utility and performance, advanced airfoil developments and engine cooling drag reduction are discussed. Noise and emission reduction is a subject that is receiving significant emphasis within the NASA programs. Also included is a description of the current status of the hydrogen injection concept as a means of both lowering emissions and increasing fuel economy.
The objective of NREL's Algal Biofuel Techno-Economic Analysis (TEA) project is to provide process modeling and analysis to support Algae Program activities, utilizing TEA models to relate key process parameters with overall economics for cultivation, processing, and conversion of algal biomass to fuels and coproducts. By quantifying economic implications of key process metrics, TEA models highlight the technical requirements to achieve future program cost goals as well as enabling a means to track progress towards these goals. This project provides high impact and relevance though generation of critical cost data tied to funded research, with our analyses subsequently exercised by BETO to guide program plans, FOA priorities, and other directives. This includes costs for both algal biomass production and downstream conversion, most notably to support BETO's fuel cost targets below $2.5/GGE by 2030. To mitigate a key risk/challenge in constraining our work to academic analyses rooted only in future projections, our work also seeks to provide near-term value to today's algae industry through frequent industry engagement, while maintaining close ties with other BETO collaborators. This project has made numerous accomplishments since the 2019 peer review, including a continued focus on opportunities for value-added products, with related analyses for new pathway opportunities to achieve BETO cost goals and notable State-of-Technology (SOT) improvements over prior cost benchmarks.
Public support is growing for policy initiatives to spur a transition from a fossil to renewable energy portfolio in the electricity sector. Some utilities in the United States offer programs that allow consumers to voluntarily pay premiums (0.1-7.0 cents/kWh) for electricity from renewable sources. However, it is unclear whether public support translates to paying for green electricity if given the option. Our analysis employs data from two national, longitudinal surveys on energy attitudes and willingness to pay for renewables to investigate whether environmental concerns and stated preferences for renewable energy translate to consumer behavior as measured through ratepayer participation in voluntary utility renewable energy programs known as utility green pricing. We find higher green pricing program participation rates in areas where consumers have stronger feelings about the environmental impacts of energy. Consumers in high-participation areas also have a higher stated willingness to pay for renewable energy, on average, than consumers in low-participation areas. We also find income, homeownership, and home value explain some of the difference between high- and low-participation programs. Further, program participation is lower in areas where utilities charge higher green pricing program premiums. These findings suggest that green power programs - such as utility green pricing - offer a market-based mechanism for consumers to realize their desire to purchase renewable energy. Policymakers may use these results to support further expansion of green power programs in areas where customers currently lack accessible and affordable options to act on their environmental beliefs and concerns.
The Solid Rocket Booster (SRB) element integrates all the subsystems needed for ascent flight, entry, and recovery of the combined Booster and Motor system. These include the structures, avionics, thrust vector control, pyrotechnic, range safety, deceleration, thermal protection, and retrieval systems. This represents the only human-rated, recoverable and refurbishable solid rocket ever developed and flown. Challenges included subsystem integration, thermal environments and severe loads (including water impact), sometimes resulting in hardware attrition. Several of the subsystems evolved during the program through design changes. These included the thermal protection system, range safety system, parachute/recovery system, and others. Obsolescence issues occasionally required component recertification. Because the system was recovered, the SRB was ideal for data and imagery acquisition, which proved essential for understanding loads and system response. The three main parachutes that lower the SRBs to the ocean are the largest parachutes ever designed, and the SRBs are the largest structures ever to be lowered by parachutes. SRB recovery from the ocean was a unique process and represented a significant operational challenge; requiring personnel, facilities, transportation, and ground support equipment. The SRB element achieved reliability via extensive system testing and checkout, redundancy management, and a thorough postflight assessment process. Assembly and integration of the booster subsystems was a unique process and acceptance testing of reused hardware components was required for each build. Extensive testing was done to assure hardware functionality at each level of stage integration. Because the booster element is recoverable, subsystems were available for inspection and testing postflight, unique to the Shuttle launch vehicle. Problems were noted and corrective actions were implemented as needed. The postflight assessment process was quite detailed and a significant portion of flight operations. The SRBs provided fully redundant critical systems including thrust vector control, mission critical pyrotechnics, avionics, and parachute recovery system. The design intent was to lift off with full redundancy. On occasion, the redundancy management scheme was needed during flight operations. This paper describes some of the design challenges, how the design evolved with time, and key areas where hardware reusability contributed to improved system level understanding.
The NASA OAST Propulsion, Power, and Energy Division supports a low-thrust propulsion program aimed at providing high-performance options for a broad range of near-term and far-term missions and vehicles. Low-thrust propulsion has a major impact on the mission performance of essentially all spacecraft and vehicles. On-orbit lifetimes, payloads, and trip time are significantly impacted by low-thrust propulsion performance and integration features for earth-to-orbit (ETO) vehicles, earth-orbit and planetary spacecraft, and large platforms in earth orbit. Major emphases are on low-thrust chemical propulsion, both storables and hydrogen/oxygen; low-power (auxiliary) electric arcjets and resistojets; and high-power (primary) electric propulsion, including ion, magnetoplasmadynamic (MPD), and electrodeless concepts. The major recent accomplishments of the program are presented and their impacts discussed.
A detailed presentation is given in the form of viewgraphs on principal investigator requirements ranging from simple to complex payloads. It is stated that the program was very important to the US science community, and that there was already concern that its funding was under stress, impacting the number of missions flown, down from around 44 to 25 or so. It is also stated that the program needs more help at NASA HQ.