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All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

Recent Improvements to the Copernicus Trajectory Design and Optimization System

Copernicus is a software tool for spacecraft trajectory design and optimization. The latest version (v3.0.1) was released in October 2011. It is available at no cost to NASA centers, government contractors, and organizations with a contractual affiliation with NASA. This paper is a brief overview of the recent development history of Copernicus. An overview of the evolution of the software and a discussion of significant new features and improvements is given, and how the tool is used to design spacecraft missions

Williams, Jacob↗
NASA NTRS1992

Ion Thruster Development at NASA Lewis Research Center

Recent ion propulsion technology efforts at NASA's Lewis Research Center including development of kW-class xenon ion thrusters, high power xenon and krypton ion thrusters, and power processors are reviewed. Thruster physical characteristics, performance data, life projections, and power processor component technology are summarized. The ion propulsion technology program is structured to address a broad set of mission applications from satellite stationkeeping and repositioning to primary propulsion using solar or nuclear power systems.

Sovey, James S.↗
NASA NTRS2000

Strategic Project Management at the NASA Kennedy Space Center

This paper describes Project Management at NASA's Kennedy Space Center (KSC) from a strategic perspective. It develops the historical context of the agency and center's strategic planning process and illustrates how now is the time for KSC to become a center which has excellence in project management. The author describes project management activities at the center and details observations on those efforts. Finally the author describes the Strategic Project Management Process Model as a conceptual model which could assist KSC in defining an appropriate project management process system at the center.

Lavelle, Jerome P.↗
NASA NTRS1989

Computational Fluid Dynamics Program at NASA Ames Research Center

The Computational Fluid Dynamics (CFD) Program at NASA Ames Research Center is reviewed and discussed. The technical elements of the CFD Program are listed and briefly discussed. These elements include algorithm research, research and pilot code development, scientific visualization, advanced surface representation, volume grid generation, and numerical optimization. Next, the discipline of CFD is briefly discussed and related to other areas of research at NASA Ames including experimental fluid dynamics, computer science research, computational chemistry, and numerical aerodynamic simulation. These areas combine with CFD to form a larger area of research, which might collectively be called computational technology. The ultimate goal of computational technology research at NASA Ames is to increase the physical understanding of the world in which we live, solve problems of national importance, and increase the technical capabilities of the aerospace community. Next, the major programs at NASA Ames that either use CFD technology or perform research in CFD are listed and discussed. Briefly, this list includes turbulent/transition physics and modeling, high-speed real gas flows, interdisciplinary research, turbomachinery demonstration computations, complete aircraft aerodynamics, rotorcraft applications, powered lift flows, high alpha flows, multiple body aerodynamics, and incompressible flow applications. Some of the individual problems actively being worked in each of these areas is listed to help define the breadth or extent of CFD involvement in each of these major programs. State-of-the-art examples of various CFD applications are presented to highlight most of these areas. The main emphasis of this portion of the presentation is on examples which will not otherwise be treated at this conference by the individual presentations. Finally, a list of principal current limitations and expected future directions is given.

Holst, Terry L.↗
NASA NTRS2005

Artificial Neural Network Test Support Development for the Space Shuttle PRCS Thrusters

A significant anomaly, Fuel Valve Pilot Seal Extrusion, is affecting the Shuttle Primary Reaction Control System (PRCS) Thrusters, and has caused 79 to fail. To help address this problem, a Shuttle PRCS Thruster Process Evaluation Team (TPET) was formed. The White Sands Test Facility (WSTF) and Boeing members of the TPET have identified many discrete valve current trace characteristics that are predictive of the problem. However, these are difficult and time consuming to identify and trend by manual analysis. Based on this exhaustive analysis over months, 22 thrusters previously delivered by the Depot were identified as high risk for flight failures. Although these had only recently been installed, they had to be removed from Shuttles OV103 and OV104 for reprocessing, by directive of the Shuttle Project Office. The resulting impact of the thruster removal, replacement, and valve replacement was significant (months of work and hundreds of thousands of dollars). Much of this could have been saved had the proposed Neural Network (NN) tool described in this paper been in place. In addition to the significant benefits to the Shuttle indicated above, the development and implementation of this type of testing will be the genesis for potential Quality improvements across many areas of WSTF test data analysis and will be shared with other NASA centers. Future tests can be designed to incorporate engineering experience via Artificial Neural Nets (ANN) into depot level acceptance of hardware. Additionally, results were shared with a NASA Engineering and Safety Center (NESC) Super Problem Response Team (SPRT). There was extensive interest voiced among many different personnel from several centers. There are potential spin-offs of this effort that can be directly applied to other data acquisition systems as well as vehicle health management for current and future flight vehicles.

Lehr, Mark E.↗
NASA NTRS1972

Employee Communication at the NASA Langley Research Center

The means of employee communication at the NASA Langley Research Center are reported, and their effectiveness evaluated. The history, purpose, and structure of the organization as well as the employee educational background and salary status are discussed. Some of the approaches used by Langley Research Center management in communicating with their men are addressed and compared with recommendations of experts in employee communication. The results of personal interviews involving both employee and management assessment of management-employee communication are presented and evaluated. Employees need a great deal more recommunication from management providing rationale behind the cancellation of existing projects or the disapproval of proposed research projects. Also NASA management needs to establish a policy and guidelines for the rapid and simultaneous dissemination of all non-restricted information to employees during organizational activities having potential adverse effects on large numbers of personnel. Finally some improvements should be made in employee orientation procedures.

Bendura, R. J.↗
NASA NTRS2014

Climate Change and Vector Borne Diseases on NASA Langley Research Center

Increasing global temperature, weather patterns with above average storm intensities, and higher sea levels have been identified as phenomena associated with global climate change. As a causal system, climate change could contribute to vector borne diseases in humans. Vectors of concern originate from the vicinity of Langley Research Center include mosquitos and ticks that transmit disease that originate regionally, nationwide, or from outside the US. Recognizing changing conditions, vector borne diseases propagate under climate change conditions, and understanding the conditions in which they may exist or propagate, presents opportunities for monitoring their progress and mitigating their potential impacts through communication, continued monitoring, and adaptation. Personnel comprise a direct and fundamental support to NASA mission success, continuous and improved understanding of climatic conditions, and the resulting consequence of disease from these conditions, helps to reduce risk in terrestrial space technologies, ground operations, and space research. This research addresses conditions which are attributed to climatic conditions which promote environmental conditions conducive to the increase of disease vectors. This investigation includes evaluation of local mosquito population count and rainfall data for statistical correlation and identification of planning recommendations unique to LaRC, other NASA Centers to assess adaptation approaches, Center-level planning strategies.

Cole, Stuart K.↗
NASA NTRS2010

LCROSS: A High Return, Small Satellite Mission

Early in 2006, the NASA Exploration Systems Mission Directorate (ESMD) held a competition for NASA Centers to propose innovative ideas for a secondary payload mission to launch with the Lunar Reconnaissance Orbiter (LRO) to the Moon. The successful proposal could cost no more than $80 million dollars (less was preferred), would have to be ready to launch with the LRO in 31 months, could weigh no more than 1000 kg (fuelled), and would be designated a risk-tolerant "Class D" mission. In effect, NASA was offering a fixed-price contract to the winning NASA team to stay within a cost and schedule cap by accepting an unusually elevated risk position. To address this Announcement of Opportunity to develop a cost-and-schedule-capped secondary payload mission to fly with LRO, NASA Ames Research Center (ARC) in Moffett Field, CA, USA embarked on a brainstorming effort termed "Blue Ice" in which a small team was asked to explore a number of mission scenarios that might have a good chance for success and still fit within the stated programmatic constraints. From this work, ARC developed and submitted six of the nineteen mission proposals received by ESMD from throughout the Agency, one of which was LCROSS - a collaborative effort between ARC and its industrial partner, Northrop-Grumman (NG) in Redondo Beach, CA, USA.

Andrews, Daniel R.↗
NASA NTRS1989

Futurepath: The Story of Research and Technology at NASA Lewis Research Center

The story of research and technology at NASA Lewis Research Center's Structures Division is presented. The job and designs of the Structures Division needed for flight propulsion is described including structural mechanics, structural dynamics, fatigue, and fracture. The video briefly explains why properties of metals used in structural mechanics need to be tested. Examples of tests and simulations used in structural dynamics (bodies in motion) are briefly described. Destructive and non-destructive fatigue/fracture analysis is also described. The arc sprayed monotape (a composite material) is explained, as are the programs in which monotape plays a roll. Finally, the National Aero-Space Plane (NASP or x-30) is introduced, including the material development and metal matrix as well as how NASP will reduce costs for NASA.

Source record↗
NASA NTRS1988

Analysis of the dedicated laser velocimeter systems at NASA - Langley Research Center

Three representative laser velocimeter systems used at NASA - Langley Research Center are described and analyzed. They range from a small orthogonal three component system used for detailed aerodynamic investigations to a large two component system used for investigations of complicated helicopter rotor flow fields. The components used in each system are described and analyzed for their contributions to the measurement uncertainty. Example flow field measurements are presented to illustrate the capabilities of these systems.

Meyers, James F.↗
NASA NTRS2001

Reduced-Order Modeling: Cooperative Research and Development at the NASA Langley Research Center

Cooperative research and development activities at the NASA Langley Research Center (LaRC) involving reduced-order modeling (ROM) techniques are presented. Emphasis is given to reduced-order methods and analyses based on Volterra series representations, although some recent results using Proper Orthogonal Deco in position (POD) are discussed as well. Results are reported for a variety of computational and experimental nonlinear systems to provide clear examples of the use of reduced-order models, particularly within the field of computational aeroelasticity. The need for and the relative performance (speed, accuracy, and robustness) of reduced-order modeling strategies is documented. The development of unsteady aerodynamic state-space models directly from computational fluid dynamics analyses is presented in addition to analytical and experimental identifications of Volterra kernels. Finally, future directions for this research activity are summarized.

Silva, Walter A.↗
NASA NTRS2007

High Pressure Low NOx Emissions Research: Recent Progress at NASA Glenn Research Center

In collaboration with U.S. aircraft engine companies, NASA Glenn Research Center has contributed to the advancement of low emissions combustion systems. For the High Speed Research Program (HSR), a 90% reduction in nitrogen oxides (NOx) emissions (relative to the then-current state of the art) has been demonstrated in sector rig testing at General Electric Aircraft Engines (GEAE). For the Advanced Subsonic Technology Program (AST), a 50% reduction in NOx emissions relative to the 1996 International Civil Aviation Organization (ICAO) standards has been at demonstrated in sector rigs at both GEAE and Pratt & Whitney (P&W). During the Ultra Efficient Engine Technology Program (UEET), a 70% reduction in NOx emissions, relative to the 1996 ICAO standards, was achieved in sector rig testing at Glenn in the world class Advanced Subsonic Combustion Rig (ASCR) and at contractor facilities. Low NOx combustor development continues under the Fundamental Aeronautics Program. To achieve these reductions, experimental and analytical research has been conducted to advance the understanding of emissions formation in combustion processes. Lean direct injection (LDI) concept development uses advanced laser-based non-intrusive diagnostics and analytical work to complement the emissions measurements and to provide guidance for concept improvement. This paper describes emissions results from flametube tests of a 9- injection-point LDI fuel/air mixer tested at inlet pressures up to 5500 kPa. Sample results from CFD and laser diagnostics are also discussed.

Chi-Ming, Lee↗
NASA NTRS2010

Acoustic Calibration of the Exterior Effects Room at the NASA Langley Research Center

The Exterior Effects Room (EER) at the NASA Langley Research Center is a 39-seat auditorium built for psychoacoustic studies of aircraft community noise. The original reproduction system employed monaural playback and hence lacked sound localization capability. In an effort to more closely recreate field test conditions, a significant upgrade was undertaken to allow simulation of a three-dimensional audio and visual environment. The 3D audio system consists of 27 mid and high frequency satellite speakers and 4 subwoofers, driven by a real-time audio server running an implementation of Vector Base Amplitude Panning. The audio server is part of a larger simulation system, which controls the audio and visual presentation of recorded and synthesized aircraft flyovers. The focus of this work is on the calibration of the 3D audio system, including gains used in the amplitude panning algorithm, speaker equalization, and absolute gain control. Because the speakers are installed in an irregularly shaped room, the speaker equalization includes time delay and gain compensation due to different mounting distances from the focal point, filtering for color compensation due to different installations (half space, corner, baffled/unbaffled), and cross-over filtering.

Faller, Kenneth J., II↗
NASA NTRSDate not supplied

Resolution of Maldi-Tof Compared to Whole Genome Sequencing for Identification of Bacillus Species Isolated From Cleanrooms at Nasa Johnson Space Center

The Astromaterials Acquisition and Curation Office at NASA Johnson Space Center maintains cleanrooms to archive extraterrestrial materials returned from space exploration missions. Compared to typical built environments, oligotrophic conditions make these facilities inhospitable to microbes. Despite these controls, bacteria and fungi are regularly cultured from these cleanrooms. In particular, Bacillus sp. are frequently isolated during routine microbial monitoring. Endospores associated with this genus can survive extreme environments, such as cleanrooms. This microbial contamination may affect the integrity of astromaterials.

Microbiology↗
NASA NTRS2006

Incident Involving 30-Ah Li-ion Cell at NASA Glenn Research Center

The key lesson learned from the February 17, 2006 cell explosion incident is that PC-based test-systems, even those having built-in watchdog monitors, can lose control and malfunction. In the case of lithiumion cell/battery testing, the stored energy can be released explosively causing considerable injury and damage to facilities. The investigation showed that although the Arbin system has a built-in watchdog monitor, the circumstances of the incident defeated the action of the watchdog and allowed the cycler to continue operation without control. An upgrade to the most recent version of Arbin software (version 4) was provided as a fix to the presumed control problem. This upgrade included newer EPROM s for the cycler microprocessor. Investigation revealed that similar incidents have occurred at other NASA centers with a variety of PC-based test instruments. JPL suffered an incident with Maccor testers and the GRC fuel cell group observed similar problems with LabView software. This is not exclusively an Arbin problem, but an issue with all PC-based systems. In this incident, it was fortunate that the event occurred after-hours with no-one in the room. The facility arrangement placed control consoles adjacent to the test chamber doors. Had someone been in the room during the event, they would have been exposed to hot debris and toxic combustion products. It was also fortunate that the exploded cell stayed inside the chamber after the door was forced open. If the cell had been ejected into the room it could have caused serious facility damage by impact and possibly caused a fire in the facility.

Bennett, William↗
NASA NTRS2010

Human Factors, Habitability and Environmental Health and the Human Integration Design Handbook

For decades, Space Life Sciences and NASA as an Agency have considered NASA-STD-3000, Man-Systems Integration Standards, a significant contribution to human spaceflight programs and to human-systems integration in general. The document has been referenced in numerous design standards both within NASA and by organizations throughout the world. With research program and project results being realized, advances in technology and new information in a variety of topic areas now available, the time arrived to update this extensive suite of requirements and design information. During the past several years, a multi-NASA center effort has been underway to write the update to NASA-STD-3000 with standards and design guidance that would be applicable to all future human spaceflight programs. NASA-STD-3001 - Volumes 1 and 2 - and the Human Integration Design Handbook (HIDH) were created. Volume 1, Crew Health, establishes NASA s spaceflight crew health standards for the pre-flight, in-flight, and post-flight phases of human spaceflight. Volume 2, Human Factors, Habitability and Environmental Health, focuses on the requirements of human-system integration and how the human crew interacts with other systems, and how the human and the system function together to accomplish the tasks for mission success. The HIDH is a compendium of human spaceflight history and knowledge, and provides useful background information and research findings. And as the HIDH is a stand-alone companion to the Standards, the maintenance of the document has been streamlined. This unique and flexible approach ensures that the content is current and addresses the fundamental advances of human performance and human capabilities and constraints research. Current work focuses on the development of new sections of Volume 2 and collecting updates to the HIDH. The new sections in development expand the scope of the standard and address mission operations and support operations. This effort is again collaboration with representatives from the Johnson Space Center Missions Operations and Space Life Sciences Directorates and the Engineering Directorate from Kennedy Space Center as well as discipline experts from across the Agency.

Houbec, Keith↗
NASA NTRS1989

Proceedings of the Second Noncontact Temperature Measurement Workshop

The state of the art in noncontact temperature measurement (NCTM) technology was reviewed and the NCTM requirements of microgravity materials processing community identified. The workshop included technical presentations and discussions which ranged from research on advanced concepts for temperature measurement to laboratory research and development regarding measurement principles and state-of-the-art engineering practices for NCTM methodology in commercial and industrial applications. Technical presentations were made concerning: NCTM needs as perceived by several NASA centers, recent ground-based NCT, research and development of industry, NASA, academia, and selected national laboratories, work-in-progress communication, and technical issues of the implementation of temperature measurement in the space environment to facilitate future U.S. materials science investigations.

Hale, Robert R.↗