Search NASA⌕ Search

SEARCH · Search NASA

Results for “technology assessment”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 433 records · Page 24

Lightning mapping sensor study

A technology assessment to determine how a world-wide, continuous measurement of lightning could be achieved from a geostationary platform is provided. Various approaches to the detector sensors are presented. It was first determined that any existing detector chips would require some degree of modification in order to meet the lightning mapper sensor requirements. The elements of the system were then analyzed, categorized, and graded for study emphasis. The recommended approach for the lightning mapper sensor is to develop a monolithic array in which each detector cell has circuitry that implements a two-step photon-collecting method for a very high dynamic range with good measurement accuracy. The efficiency of the array is compatible with the use of a conventional refractive optics design having an aperture in the neighborhood of 7 to 10 cm.

Norwood, V.↗

Space Station Systems Analysis Study. Volume 2: Program options, book 1, parts 1 and 2

Program options are defined and requirements are determined for integrating crew, mass, volume, and electrical power for a space construction base which incorporates the space shuttle external tanks. Orbits, stabilization, flight control hardware, as well as modules and aids for orbital assembly and servicing are considered. The effectiveness of various program options for life science and radio astronomy missions, for the solar terrestrial observatory, and for public service platforms is assessed. Technology development items are identified and costs are estimated.

Source record↗

Autonomous Integrated Receive System (AIRS) requirements definition. Volume 2: Design and development

Functional requirements and specifications are defined for an autonomous integrated receive system (AIRS) to be used as an improvement in the current tracking and data relay satellite system (TDRSS), and as a receiving system in the future tracking and data acquisition system (TDAS). The AIRS provides improved acquisition, tracking, bit error rate (BER), RFI mitigation techniques, and data operations performance compared to the current TDRSS ground segment receive system. A computer model of the AIRS is used to provide simulation results predicting the performance of AIRS. Cost and technology assessments are included.

Chie, C. M.↗

Second-generation Space Shuttle

This is a review of an in-house study at the Langley Research Center to identify the technology requirements that are necessary to develop a second-generation Space Shuttle in the post 2000 time period. The study, Future Space Transportation System Study, had two main objectives: (1) to define the launch-vehicle concepts which best meet the needs and opportunities for improved space transportation economics and capabilities for a Space Shuttle replacement and (2) to extend the level of technology assessments with respect to previous advanced system studies, especially in the areas of stuctures, propellant tankage, thermal protection systems, aerodynamics, and operations.

Arrington, J. P.↗

Solar Pond Overview

The term solar pond is used to refer specifically to a salt-gradient solar pond. A technology assessment was done consisting of thermal performance; maintenance; applications; and economics. Research needs and recommendations were also included.

French, R. L.↗

Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project. ACT/Control/Guidance System study. Volume 2: Appendices

The integrated application of active controls (IAAC) technology to an advanced subsonic transport is reported. Supplementary technical data on the following topics are included: (1) 1990's avionics technology assessment; (2) function criticality assessment; (3) flight deck system for total control and functional features list; (4) criticality and reliability assessment of units; (5) crew procedural function task analysis; and (6) recommendations for simulation mechanization.

Source record↗

Spaceborne power systems preference analyses. Volume 1: Summary

Sixteen alternative spaceborne nuclear power system concepts were ranked using multiattribute decision analysis to identify promising concepts for further technology development. Four groups interviewed were: safety, systems definition and design, technology assessment, and mission analysis. The ranking results were consistent from group and for different utility function models for individuals.

Smith, J. H.↗

Environmental control and life support system analysis tools for the Space Station era

This paper describes the concept of a developing emulation, simulation, sizing, and technology assessment program (ESSTAP) which can be used effectively for the various functional disciplines (structures, power, ECLSS, etc.) beginning with the initial system selection and conceptual design processes and continuing on through the mission operation and growth phases of the Space Station for the purpose of minimizing overall program costs. It will discuss the basic requirements for these tools, as currently envisioned for the Environmental Control and Life Support System (ECLSS), identifying their intended and potential uses and applications, and present examples and status of several representative tools. The development and applications of a Space Station Atmospheric Revitalization Subsystem (ARS) demonstration model to be used for concent verification will also be discussed.

Blakely, R. L.↗

Electrical power systems for Space Station

Major challenges in power system development are described. Evolutionary growth, operational lifetime, and other design requirements are discussed. A pictorial view of weight-optimized power system applications shows which systems are best for missions of various lengths and required power level. Following definition of the major elements of the electrical power system, an overview of element options and a brief technology assessment are presented. Selected trade-study results show end-to-end system efficiencies, required photovoltaic power capability as a function of energy storage system efficiency, and comparisons with other systems such as a solar dynamic power system.

Simon, W. E.↗

Application of intersatellite links to domestic satellite systems

The results of a study on intersatellite link (ISL) applications for domestic satellite communications are presented. It was determined if any technical, economic, or performance benefits could be gained by introducing intersatellite links into a domestic satellite communication network. Several key systems issues of domestic ISL's are addressed. These include the effect of a skewed traffic distribution on the selection of ISL satellite orbit locations, tolerable satellite spacing, and crosslink traffic-handling requirements. An ISL technology assessment is made by performing a parametric link analysis for several microwave and optical implementations. The impact of the crosslink on the end-to-end link performance is investigated for both regenerative and nonregenerative ISL architectures. A comparison is made between single satellite systems operating at C-, and Ku-bands and the corresponding ISL systems in terms of ground segment cost, space segment cost, and net link performance. Results indicate that ISL's can effectively expand the CONUS orbital arc, with a 60 GHz ISL implementation being the most attractive.

Ponchak, D. S.↗

Thermal energy storage for a space solar dynamic power system

In the past, NASA has employed solar photovoltaic devices for long-duration missions. Thus, the Skylab system has operated with a silicon photovoltaic array and a nickel-cadmium electrochemical system energy storage system. Difficulties regarding the employment of such a system for the larger power requirements of the Space Station are related to a low orbit system efficiency and the large weight of the battery. For this reason the employment of a solar dynamic power system (SDPS) has been considered. The primary components of an SDPS include a concentrating mirror, a heat receiver, a thermal energy storage (TES) system, a thermodynamic heat engine, an alternator, and a heat rejection system. The heat-engine types under consideration are a Brayton cycle engine, an organic Rankine cycle engine, and a free-piston/linear-alternator Stirling cycle engine. Attention is given to a system description, TES integration concepts, and a TES technology assessment.

Faget, N. M.↗

Application of intersatellite links to domestic satellite systems

The results of a study on intersatellite link (ISL) applications for domestic satellite communications are presented. It was determined if any technical, economic, or performance benefits could be gained by introducing intersatellite links into a domestic satellite communication network. Several key systems issues of domestic ISL's are addressed. These include the effect of a skewed traffic distribution on the selection of ISL satellite orbit locations, tolerable satellite spacing, and crosslink traffic-handling requirements. An ISL technology assessment is made by performing a parametric link analysis for several microwave and optical implementations. The impact of the crosslink on the end-to-end link performance is investigated for both regenerative and nonregenerative ISL architectures. A comparison is made between single satellite systems operating at C-, and Ku-bands and the corresponding ISL systems in terms of ground segment cost, space segment cost, and net link performance. Results indicate that ISL's can effectively expand the CONUS orbital arc, with a 60 GHz ISL implementation being the most attractive.

Ponchak, D. S.↗

National space transportation and support study/mission requirements and architecture studies

The government approach to fulfilling the requirements of the National Space Transportation and Support Study is described. DOD and NASA were required to determine the architecture and technology that would be needed for civil and defense space transportation during the 1995-2010 time range. NASA collected data from the National Commission on Space and the DOD research focused on SDI requirements. The objectives and recommendations of the space transportation architecture, transportation and support systems, and technology assessment and planning tasks are discussed.

Durocher, C. L.↗

Advanced operator/system interface concepts for the Space Station

Concepts and data developed as part of the Preliminary Space Station Automation and Robotics Plan are reviewed as well as candidate selection criteria, technology assessments, and preliminary candidate recommendations. A need for development of advanced operator/systems interface (OSI) concepts to support future Space Station automation and robotics applications is identified. Four candidate applications, illustrating the potential benefits of an advanced OSI, are described. These include: (1) a conversational OSI system, (2) a laboratory experiment manipulator system, (3) a module safety advisor, and (4) an integrated maintenance/training system. These specific automation and robotics applications are expected to occur relatively early in the growth of the Space Station and to provide significant commercial and station benefits throughout the life of the station.

Case, C. M.↗

ESA activities in space laser sounding and ranging

Laser remote sensing from space is undoubtedly one of the most promising means to obtain essential atmospheric and geophysical parameters on a global scale. Efforts including feasibility assessments, technology developments, and mission definition studies are in progress at the European Space Agency (ESA) to prepare for the prospective use of laser remote sensing systems in space. An overview of the programs under way is presented and the perspectives of laser remote sensing in the context of ESA's Long-Term European Space Plan are discussed.

Lutz, H.↗

Chemical production on Mars using in situ propellant production technology

In situ propellant production (ISPP) was examined in terms of its applicability to a manned Mars mission. Production of oxygen from Martian atmosphere was used as the baseline system for ISPP technology assessment. It was concluded that production of oxygen was an important element in a manned Mars mission which could be developed in terrestrial laboratories. Expert system methodology will be required to enable reliable, autonomous production of oxygen. Furthermore, while no major technical breakthroughs are required, this research requires a long lead time to permit its systematic evolution.

Robert L Ash↗

Cryogenic gear technology for an orbital transfer vehicle engine and tester design

Technology available for gears used in advanced Orbital Transfer Vehicle rocket engines and the design of a cryogenic adapted tester used for evaluating advanced gears are presented. The only high-speed, unlubricated gears currently in cryogenic service are used in the RL10 rocket engine turbomachinery. Advanced rocket engine gear systems experience operational load conditions and rotational speed that are beyond current experience levels. The work under this task consisted of a technology assessment and requirements definition followed by design of a self-contained portable cryogenic adapted gear test rig system.

Calandra, M.↗

Frontiers of technology

An evaluation is made of the Space Station technology assessment efforts conducted by NASA under its Advanced Development Program, which has over the last three years enlisted 14 different disciplines in the refinement of every aspect of Space Station interior and exterior design. Major investigations have delved into the application of novel coatings to materials subjected to prolonged exposure to radiation, the design of berthing and docking mechanisms, the demonstration of EVA structural assembly methods in a neutral buoyancy water tank, and an investigation of the effects of meteoroids and space debris on EVA garments, which have prompted the development of a novel 'hard' suit.

Carlisle, R.↗