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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 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Algorithms for Software Development

Management aid makes changes obvious. One key element in scheme for software development control is check summing. If check sum for given line in source file is different from previous version, it is evident change has been made. Subsequent editing of file creates new lines, deletes old ones, modifies characters, moves lines, or copies (reuse) existing lines. Combination of three elements of line code permits all transactions to be detected.

Tausworthe, R. C.↗
NASA NTRS1986

Orbital transfer vehicle launch operations study. Volume 2: Detailed summary

A series of Operational Design Drivers were identified. Several of these could have significant impact(s) on program costs. These recommendations, for example, include such items as: complete factory assembly and checkout prior to shipment to the ground launch site to make significant reductions in time required at the launch site as well as overall manpower required to do this work; minimize use of nonstandard equipment when orbiter provided equipment is available; and require commonality (or interchangeability) of subsystem equipment elements that are common to the space station, Orbit Maneuvering Vehicles, and/or Orbit Transfer Vehicles. Several additional items were identified that will require a significant amount of management attention (and direction) to resolve. Key elements of the space based processing plans are discussed.

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NASA NTRS1987

Space Station Information System - Concepts and international issues

The Space Station Information System (SSIS) is outlined in terms of its functions and probable physical facilities. The SSIS includes flight element systems as well as existing and planned institutional systems such as the NASA Communications System, the Tracking and Data Relay Satellite System, and the data and communications networks of the international partners. The SSIS strives to provide both a 'user friendly' environment and a software environment which will allow for software transportability and interoperability across the SSIS. International considerations are discussed as well as project management, software commonality, data communications standards, data security, documentation commonality, transaction management, data flow cross support, and key technologies.

Williams, R. B.↗
NASA NTRS1988

An initiative in multidisciplinary optimization of rotorcraft

Described is a joint NASA/Army initiative at the Langley Research Center to develop optimization procedures aimed at improving the rotor blade design process by integrating appropriate disciplines and accounting for important interactions among the disciplines. The activity is being guided by a Steering Committee made up of key NASA and Army researchers and managers. The committee, which has been named IRASC (Integrated Rotorcraft Analysis Steering Committee), has defined two principal foci for the activity: a white paper which sets forth the goals and plans of the effort; and a rotor design project which will validate the basic constituents, as well as the overall design methodology for multidisciplinary optimization. The paper describes the optimization formulation in terms of the objective function, design variables, and constraints. Additionally, some of the analysis aspects are discussed and an initial attempt at defining the interdisciplinary couplings is summarized. At this writing, some significant progress has been made, principally in the areas of single discipline optimization. Results are given which represent accomplishments in rotor aerodynamic performance optimization for minimum hover horsepower, rotor dynamic optimization for vibration reduction, and rotor structural optimization for minimum weight.

Adelman, Howard M.↗
NASA NTRS1986

A database management capability for Ada

The data requirements of mission critical defense systems have been increasing dramatically. Command and control, intelligence, logistics, and even weapons systems are being required to integrate, process, and share ever increasing volumes of information. To meet this need, systems are now being specified that incorporate data base management subsystems for handling storage and retrieval of information. It is expected that a large number of the next generation of mission critical systems will contain embedded data base management systems. Since the use of Ada has been mandated for most of these systems, it is important to address the issues of providing data base management capabilities that can be closely coupled with Ada. A comprehensive distributed data base management project has been investigated. The key deliverables of this project are three closely related prototype systems implemented in Ada. These three systems are discussed.

Chan, Arvola↗
NASA NTRS1989

An initiative in multidisciplinary optimization of rotorcraft

Described is a joint NASA/Army initiative at the Langley Research Center to develop optimization procedures aimed at improving the rotor blade design process by integrating appropriate disciplines and accounting for important interactions among the disciplines. The activity is being guided by a Steering Committee made up of key NASA and Army researchers and managers. The committee, which has been named IRASC (Integrated Rotorcraft Analysis Steering Committee), has defined two principal foci for the activity: a white paper which sets forth the goals and plans of the effort; and a rotor design project which will validate the basic constituents, as well as the overall design methodology for multidisciplinary optimization. The optimization formulation is described in terms of the objective function, design variables, and constraints. Additionally, some of the analysis aspects are discussed and an initial attempt at defining the interdisciplinary couplings is summarized. At this writing, some significant progress has been made, principally in the areas of single discipline optimization. Results are given which represent accomplishments in rotor aerodynamic performance optimization for minimum hover horsepower, rotor dynamic optimization for vibration reduction, and rotor structural optimization for minimum weight.

Adelman, Howard M.↗
NASA NTRS1989

Study of high-speed civil transports

A systems study to identify the economic potential for a high-speed commercial transport (HSCT) has considered technology, market characteristics, airport infrastructure, and environmental issues. Market forecasts indicate a need for HSCT service in the 2000/2010 time frame conditioned on economic viability and environmental acceptability. Design requirements focused on a 300 passenger, 3 class service, and 6500 nautical mile range based on the accelerated growth of the Pacific region. Compatibility with existing airports was an assumed requirement. Mach numbers between 2 and 25 were examined in conjunction with the appropriate propulsion systems, fuels, structural materials, and thermal management systems. Aircraft productivity was a key parameter with aircraft worth, in comparison to aircraft price, being the airline-oriented figure of merit. Aircraft screening led to determination that Mach 3.2 (TSJF) would have superior characteristics to Mach 5.0 (LNG) and the recommendation that the next generation high-speed commercial transport aircraft use a kerosene fuel. The sensitivity of aircraft performance and economics to environmental constraints (e.g., sonic boom, engine emissions, and airport/community noise) was identified together with key technologies. In all, current technology is not adequate to produce viable HSCTs for the world marketplace. Technology advancements must be accomplished to meet environmental requirements (these requirements are as yet undetermined for sonic boom and engine emissions). High priority is assigned to aircraft gross weight reduction which benefits both economics and environmental aspects. Specific technology requirements are identified and national economic benefits are projected.

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NASA NTRS1990

Status of integrated multidisciplinary rotorcraft optimization research at the Langley Research Center

This paper describes a joint NASA/Army research activity at the Langley Research Center to develop optimization procedures aimed at improving the rotor blade design process by integrating appropriate disciplines and accounting for important interactions among the disciplines. The activity is being guided by a Steering Committee made up of key NASA and Army researchers and managers. The paper describes the optimization formulation in terms of the objective function, design variables, and constraints. The analysis aspects are discussed, and the interdisciplinary interactions are defined in terms of the information that must be transferred among disciplinary analyses as well as the trade-offs between disciplines in determining the details of the design. At this writing, some significant progress has been made. Results given in the paper represent accomplishments in rotor aerodynamic performance optimization for minimum horsepower, rotor dynamic optimization for vibration reduction, approximate analysis of frequencies and mode shapes, rotor structural optimization for minimum weight, and integrated aerodynamic load/dynamics optimization for minimum vibration and weight.

Mantay, Wayne R.↗
NASA NTRS1992

Constant reverse thrust activated reorientation of liquid hydrogen with Geyser initiation

A key objective of the cryogenic fluid management of the spacecraft propulsion system is to develop the technology necessary for acquisition or positioning of liquid outflow or vapor venting. Numerical simulation of positive liquid acquisition is attempted by introducing reverse gravity acceleration, resulting from the propulsive thrust of auxiliary engines, which exceeds critical value for the initiation of geyser. Based on the computer simulation of flowfields during the course of fluid reorientation, six dimensionless parameters resulted in this study. It shows that these parameters hold near-constant values through the entire ranges of liquid filled levels, from 30-80 percent, during the course of fluid reorientation.

Hung, R. J.↗
NASA NTRS1997

Management of a coordinated parts program

The organization of the management of a parts program is discussed. The organizational structure faced by the parts manager and the advantages and disadvantages of managing a coordinated parts program are analyzed. The reliable operation of an instrument is the key to the success of the mission, together with the management of the parts program. The analysis led to the conclusion that the setting up of the decision support model will aid the parts manager in the decision making and the process control.

Krishnan, G. S.↗
NASA NTRS2000

The Effect of Shared Information on Pilot/Controller and Controller/Controller Interactions

The increased ability to exchange information between Pilots, Controllers, Dispatchers, and other agents is a key component of advanced Air Traffic Management. The importance of shared information as well as current and evolving practices in information sharing are presented for a variety of interactions including: Controller/Pilot interactions, Pilot/Airline interactions, Controller/Controller interactions, and Airline/ATM interactions.

Hansman, R. John↗
NASA NTRS2002

Willpower

I am struck by how often failure is blamed on a lack of discipline. You often hear losing coaches cite this as the reason for a big loss. I don't recall the last time I heard one say that his team lost a game because of his players' lack of skill. I think a breakdown in discipline is also one of the key reasons why program and project management teams fail to meet expectations. The first program I ever managed had a clear set of priorities. I understood the mandate, and so did everyone else on the team. We set an ambitious schedule and started to work fervently. Not too long into the program the customer wanted to know what performance he was going to get. I replied by categorizing the performance parameters into three bins: 1. Performance you will get. 2. Performance you may get. 3. Performance that there's no way you will get. Did that cause an uproar. The customer demanded everything in the second bin be moved to the first, and most everything in the third bin moved to the second. My immediate impulse was to agree, but I managed to overcome that. In my heart, I knew that we would never meet the already ambitious schedule if we had to deliver more performance. No was my answer. The program turned out to be a huge success, but the result would have been largely different had senior management or I failed to maintain discipline.

Little, Terry↗
NASA NTRS1984

Motor Controllers

Kollmorgen Corporation's Mermaid II two person submersible is propeller-driven by a system of five DC brushless motors with new electronic controllers that originated in work performed in a NASA/DOE project managed by Lewis Research Center. A key feature of the system is electric commutation rather than mechanical commutation for converting AC current to DC.

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NASA NTRS2005

Novel Space-based Solar Power Technologies and Architectures for Earth and Beyond

Research, development and studies of novel space-based solar power systems, technologies and architectures for Earth and beyond are needed to reduce the cost of clean electrical power for terrestrial use and to provide a stepping stone for providing an abundance of power in space, i.e., manufacturing facilities, tourist facilities, delivery of power between objects in space, and between space and surface sites. The architectures, technologies and systems needed for space to Earth applications may also be used for in-space applications. Advances in key technologies, i.e., power generation, power management and distribution, power beaming and conversion of beamed power are needed to achieve the objectives of both terrestrial and extraterrestrial applications. Power beaming or wireless power transmission (WPT) can involve lasers or microwaves along with the associated power interfaces. Microwave and laser transmission techniques have been studied with several promising approaches to safe and efficient WPT identified. These investigations have included microwave phased array transmitters, as well as laser transmission and associated optics. There is a need to produce "proof-of-concept" validation of critical WPT technologies for both the near-term, as well as far-term applications. Investments may be harvested in near-term beam safe demonstrations of commercial WPT applications. Receiving sites (users) include ground-based stations for terrestrial electrical power, orbital sites to provide power for satellites and other platforms, future space elevator systems, space vehicle propulsion, and space to surface sites. This paper briefly discusses achieving a promising approach to the solar power generation and beamed power conversion. The approach is based on a unique high-power solar concentrator array called Stretched Lens Array (SLA) for both solar power generation and beamed power conversion. Since both versions (solar and laser) of SLA use many identical components (only the photovoltaic cells need to be different), economies of manufacturing and scale may be realized by using SLA on both ends of the laser power beaming system in a space solar power application. Near-term uses of this SLA-laser-SLA system may include terrestrial and space exploration in near Earth space. Later uses may include beamed power for bases or vehicles on Mars.

Howell, Joe T.↗
NASA NTRS2006

Advanced Energy Conversion Technologies and Architectures for Earth and Beyond

Research, development and studies of novel space-based solar power systems, technologies and architectures for Earth and beyond are needed to reduce the cost of clean electrical power for terrestrial use and to provide a stepping stone for providing an abundance of power in space, i.e., manufacturing facilities, tourist facilities, delivery of power between objects in space, and between space and surface sites. The architectures, technologies and systems needed for space to Earth applications may also be used for in-space applications. Advances in key technologies, i.e., power generation, power management and distribution, power beaming and conversion of beamed power are needed to achieve the objectives of both terrestrial and extraterrestrial applications. There is a need to produce "proof-ofconcept" validation of critical WPT technologies for both the near-term, as well as far-term applications. Investments may be harvested in near-term beam safe demonstrations of commercial WPT applications. Receiving sites (users) include ground-based stations for terrestrial electrical power, orbital sites to provide power for satellites and other platforms, future space elevator systems, space vehicle propulsion, and space surface sites. Space surface receiving sites of particular interest include the areas of permanent shadow near the moon s North and South poles, where WPT technologies could enable access to ice and other useful resources for human exploration. This paper discusses work addressing a promising approach to solar power generation and beamed power conversion. The approach is based on a unique high-power solar concentrator array called Stretched Lens Array (SLA) applied to both solar power generation and beamed power conversion. Since both versions (solar and laser) of SLA use many identical components (only the photovoltaic cells need to be different), economies of manufacturing and scale may be realized by using SLA on both ends of the laser power beaming system in a space solar power application. Near-term uses of this SLA-laser-SLA system may include terrestrial and space exploration in near Earth space. Later uses may include beamed power for bases or vehicles on Mars. Strategies for developing energy infrastructures in space which utilize this technology are presented. This dual use system produces electrical energy efficiently from either coherent light, such as from a highly coherent laser, or from conventional solar illumination. This allows, for example, supplementing solar energy with energy provided by highly coherent laser illumination during periods of low solar illumination or no illumination. This reduces the need for batteries and alternate sources of power. The capability of using laser illumination in a lowest order Gaussian laser mode provides means for transmitting power optically with maximum efficiency and precision over the long distances characteristic of space. A preliminary receiving system similar to that described here, has been produced and tested under solar and laser illumination. A summary of results is given.

Howell, Joe T.↗
NASA NTRS2005

Preliminary Airspace Operations Simulations Findings Report

Provides preliminary findings of the initial series (normal operations and contingency management) of airspace operations simulations. The key elements of this report discuss feedback from controller subjects for UAS flight above FL430. Findings provide initial evaluation of routine UAS operations above dense ARTCC airspace (ZOB), and identify areas of further research, policy direction and procedural development. This document further serves as an addendum to the detailed AOS simulation plan (Deliverable SIM001), incorporating feedback from FAA air traffic personnel and Access 5 IPTs.

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NASA NTRS2010

Lessons Learned in Launching Ares I-X

The Ares I-X flight test, scheduled for 2009, is the first opportunity for the Constellation Program and Ares Projects to obtain important data on the in-flight loads, first stage recovery, and ground-handling characteristics of the Ares I crew launch vehicle. The flight test vehicle will incorporate a mix of flight and mockup hardware, reflecting an acceptable representation of the mass and outer mold line characteristics of the operational Ares I vehicle. It will be powered by a four-segment solid rocket motor from the Space Shuttle inventory and will include a fifth, inert spacer segment and new forward structures to make it the same shape as the Ares I first stage. The vehicle also includes mass simulators for the upper stage, Orion crew module, and launch abort system to match the outer mold line of Ares I; an active roll control system; and avionics derived from Shuttle and Atlas hardware. This suborbital mission will take the flight test vehicle from stacking in the Vehicle Assembly Building (VAB) at Kennedy Space Center (KSC) through liftoff, maximum dynamic pressure, first stage separation, and recovery. Ares I-X presented NASA with unique project management challenges. This presentation will address those unique challenges, including managing a virtual nationwide team under a constrained timeline; designing and building the launch vehicle and ground systems; working concurrently with Space Shuttle activities; and integrating technical and management functions. It also will identify key data collected and lessons learned from the flight that will be applied to future exploration missions.

Davis, Stephan R.↗
NASA NTRS2010

NASA Applied Sciences Program

Goal 1: Enhance Applications Research Advance the use of NASA Earth science in policy making, resource management and planning, and disaster response. Key Actions: Identify priority needs, conduct applied research to generate innovative applications, and support projects that demonstrate uses of NASA Earth science. Goal 2: Increase Collaboration Establish a flexible program structure to meet diverse partner needs and applications objectives. Key Actions: Pursue partnerships to leverage resources and risks and extend the program s reach and impact. Goal 3:Accelerate Applications Ensure that NASA s flight missions plan for and support applications goals in conjunction with their science goals, starting with mission planning and extending through the mission life cycle. Key Actions: Enable identification of applications early in satellite mission lifecycle and facilitate effective ways to integrate end-user needs into satellite mission planning

Irwin, Daniel↗