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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 937 records · Page 52
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Earth Observatory Satellite system definition study. Report 5: System design and specifications. Volume 7: Specification for EOS low cost readout station

The functional, performance, and design requirements for the Low Cost Readout Station (LCRS) which supports the Earth Observatory Satellite (EOS) data system are described. The basic LCRS consists of all hardware and software needed to acquire and track the EOS-A or EOS-B satellite and receive, record, process, and annotate the instrument data from the satellites. The LCRS also provides appropriate interfaces with the unique local user provided display and extractive processing equipment. The LCRS has the capability of acquiring image data from the EOS-A and the EOS-B satellites over a ground area defines by a 500 kilometer radius from the coordinates of the station. The LCRS is also capable of receiving and processing both, but not simultaneously, full five band Multispectral Scanner (MSS) image data and various modes of the Compacted Thematic (CTM) data.

Source record↗
NASA NTRS1986

Electrical power system design for the US space station

The multipurpose, manned, permanent space station will be our next step toward utilization of space. A multikilowatt electrical power system will be critical to its success. The power systems for the space station manned core and platforms that have been selected in definition studies are described. The system selected for the platforms uses silicon arrays and Ni-H2 batteries. The power system for the manned core is a hybrid employing arrays and batteries identical to those on the platform along with solar dynamic modules using either Brayton or organic Rankine engines. The power system requirements, candidate technologies, and configurations that were considered, and the basis for selection, are discussed.

Nored, Donald L.↗
NASA NTRS1973

System design of the Pioneer Venus spacecraft. Volume 8: Command/data handling subsystems studies

Study tasks for the command and data handling subsystems have been directed to: (1) determining ground data systems, (GDS) interfaces and deep space network (DSN) changes, if required, (2) defining subsystem requirements, (3) surveying existing hardware that could be used or modified to meet subsystem requirements, and (4) establishing a baseline design. Study of the existing GDS led to the conclusion that the Viking configuration GDS can be used with only minor changes required for the Pioneer Venus baseline. Those changes required are associated with providing a predetection recording capability used during probe entry and descent. Subsystem requirements were first formulated with sufficient latitude so that surveys of existing hardware could lead to low cost hardware which, in turn, could modify more narrowly defined subsystem requirements.

Vesely, D. D.↗
NASA NTRS1986

Feedback system design with an uncertain plant

A method is developed to design a fixed-parameter compensator for a linear, time-invariant, SISO (single-input single-output) plant model characterized by significant structured, as well as unstructured, uncertainty. The controller minimizes the H(infinity) norm of the worst-case sensitivity function over the operating band and the resulting feedback system exhibits robust stability and robust performance. It is conjectured that such a robust nonadaptive control design technique can be used on-line in an adaptive control system.

Milich, D.↗
NASA NTRS1986

Feedback system design with an uncertain plant

A method is developed to design a fixed-parameter compensator for a linear, time-invariant, SISO (single-output single-output) plant model characterized by significant structured, as well as unstructured, uncertainty. The controller minimizes the H(infinity) norm of the worst-case sensitivity function over the operating band and the resulting feedback system exhibits robust stability and robust performance. It is conjectured that such a robust nonadaptive control design technique can be used on-line in an adaptive control system.

Milich, D.↗
NASA NTRS1981

Orbiter global positioning system design and Ku-band problems investigation, exhibit B, revision 1

The LinCom effort in supporting the JSC study of the use of the Global Positioning System (GPS) on the space shuttle and in Ku-band problem investigation is documented. LinCom was tasked to evaluate system implementation, performance, and integration aspects of the shuttle GPS and to provide independent technical assessment of reports submitted to JSC regarding integration studies, system studies and navigation analyses.

Chie, C. M.↗
NASA NTRS1982

System design concepts and requirements for aeroassisted orbital transfer vehicles

The Orbital Transfer Vehicle (OTV) is an advanced upper stage concept which will deliver spacecraft from operating systems at Low Earth Orbit (LEO) such as Space Shuttle, Earth-To-Orbit (ETO) vehicles, and Space Operations Center (SOC), to High Earth Orbit (HEO) and planetary excursions. The OTV will be driven by the need to achieve significant reductions in the operational costs for delivering payloads to Geostationary Equatorial Orbit (GEO). Aeroassist is a technological capability that has a potential for OTV's ranging from mission enhancing (reusable OTV for payload delivery) to mission enabling (manned GEO and some DOD). It is shown that the use of aeroassist for OTV's is a high leverage technology which can potentially reduce space transportation costs and enable a number of highly desirable missions.

Austin, R. E.↗
NASA NTRS1988

CETF Space Station payload pointing system design and analysis feasibility study

The expected pointing performance of an attached payload coupled to the Critical Evaluation Task Force Space Station via a payload pointing system (PPS) is determined. The PPS is a 3-axis gimbal which provides the capability for maintaining inertial pointing of a payload in the presence of disturbances associated with the Space Station environment. A system where the axes of rotation were offset from the payload center of mass (CM) by 10 in. in the Z axis was studied as well as a system having the payload CM offset by only 1 inch. There is a significant improvement in pointing performance when going from the 10 in. to the 1 in. gimbal offset.

Smagala, Tom↗
NASA NTRS1989

The flight telerobotic servicer Tinman concept: System design drivers and task analysis

A study was conducted to develop a preliminary definition of the Flight Telerobotic Servicer (FTS) that could be used to understand the operational concepts and scenarios for the FTS. Called the Tinman, this design concept was also used to begin the process of establishing resources and interfaces for the FTS on Space Station Freedom, the National Space Transportation System shuttle orbiter, and the Orbital Maneuvering vehicle. Starting with an analysis of the requirements and task capabilities as stated in the Phase B study requirements document, the study identified eight major design drivers for the FTS. Each of these design drivers and their impacts on the Tinman design concept are described. Next, the planning that is currently underway for providing resources for the FTS on Space Station Freedom is discussed, including up to 2000 W of peak power, up to four color video channels, and command and data rates up to 500 kbps between the telerobot and the control station. Finally, an example is presented to show how the Tinman design concept was used to analyze task scenarios and explore the operational capabilities of the FTS. A structured methodology using a standard terminology consistent with the NASA/National Bureau of Standards Standard Reference Model for Telerobot Control System Architecture (NASREM) was developed for this analysis.

Andary, J. F.↗
NASA NTRS1991

Progress in multirate digital control system design

A new methodology for multirate sampled-data control design based on a new generalized control law structure, two new parameter-optimization-based control law synthesis methods, and a new singular-value-based robustness analysis method are described. The control law structure can represent multirate sampled-data control laws of arbitrary structure and dynamic order, with arbitrarily prescribed sampling rates for all sensors and update rates for all processor states and actuators. The two control law synthesis methods employ numerical optimization to determine values for the control law parameters. The robustness analysis method is based on the multivariable Nyquist criterion applied to the loop transfer function for the sampling period equal to the period of repetition of the system's complete sampling/update schedule. The complete methodology is demonstrated by application to the design of a combination yaw damper and modal suppression system for a commercial aircraft.

Berg, Martin C.↗
NASA NTRS1972

Space shuttle auxiliary propulsion system design study. Phase B report: Candidate RCS concept comparisons

The competing auxiliary propulsion concepts for the reusable space shuttle vehicle are defined. The concepts are compared on the basis of selection criteria such as weight, reliability, and technology requirements. Propulsion systems using both cryogenic oxygen-hydrogen and earth storable propellants were considered. Three high value oxygen-hydrogen reaction control system concepts were evaluated. The final comparisons demonstrate that all three concepts are viable design approaches. The flexibility and growth potential of the parallel concept are considered to provide an advantage over the series concept.

Orton, G. F.↗
NASA NTRS2020

Pterodactyl: Control System Design for Deployable Entry Vehicles

As space exploration missions continue to get more complex, greater demands for mass and volume are being placed on planetary entry vehicles. At the same time, the desire for precision entry targeting to enable surface missions at very specific locations is becoming common. Deployable aeroshells are one type of technology that is being developed to increase the down-mass capability of planetary entry vehicles while complying with current launch vehicle volume constraints. Propulsive control can be used for precision entry targeting but can require a large percentage of the vehicle's total mass or volume for propellant. The Pterodactyl project is studying alternative entry control systems on a Deployable Entry Vehicle to potentially introduce a mass and volume efficient entry system that can achieve precision targeting. This paper presents the mechanical design work undertaken to support the Pterodactyl trade study of three entry vehicle control system options: 1) Flaps, 2) Mass Movement, and 3) Reaction Control System.

D'Souza, Sarah↗
NASA NTRS1977

The Role of Aerospace Technology in Agriculture. The 1977 Summer Faculty Fellowship Program in Engineering Systems Design

Possibilities were examined for improving agricultural productivity through the application of aerospace technology. An overview of agriculture and of the problems of feeding a growing world population are presented. The present state of agriculture, of plant and animal culture, and agri-business are reviewed. Also analyzed are the various systems for remote sensing, particularly applications to agriculture. The report recommends additional research and technology in the areas of aerial application of chemicals, of remote sensing systems, of weather and climate investigations, and of air vehicle design. Also considered in detail are the social, legal, economic, and political results of intensification of technical applications to agriculture.

Source record↗
NASA NTRS1982

Navigation system design for a Halley sample return mission

A ballistic sample return mission to Comet Halley was recently considered by the United States. This paper describes the navigation system and the navigation strategy which would have been employed in such a mission, assuming a launch in August of 1985, an arrival at the comet in March of 1986, and a return to earth in August of 1989. Estimates of spacecraft comet- and earth-relative orbit determination accuracies are presented as functions of time. Target-relative delivery accuracies for the spacecraft and associated trajectory correction maneuver requirements are presented also.

Wood, L. J.↗
NASA NTRS2019

How Does Water Delivery System Design Impact the Microbial Load of Salad Crops?

In a microgravity setting, such as the environment aboard the International Space Station (ISS), an ideal plant water delivery system is one that can grow edible crops with minimal resource consumption and minimal risk to crew members. There are also concerns associated with the ability to control fluid escape and biofilm formation resulting in potential dangers to systems, crops, or crewmembers. To identify an appropriate system, candidate systems were assembled and operated under simulated ISS environmental conditions (T,CO2,and RH) with red romaine lettuce (Lactuca sativa cultivar 'Outredgeous') as a model crop. Fluid reservoirs and randomly selected planting sites were sampled every seven days until maturity at which point edible plant biomass and root samples were also taken. Heterotrophic bacteria and fungi growth patterns throughout each planting cycle were determined by plate counts on appropriate agar media. The candidate systems were compared to a classic hydroponics system as a control and harvested crops were compared to controls as well as Veggie-grown and market produce. Plants harvested from candidate systems yielded lower average heterotrophic bacteria and fungi per gram of plant mass levels when compared to market and Veggie samples as well as those from the control system. Additional studies to evaluate the system sanitation regimen as well as testing additional crops should be considered to aid in the selection of an ideal system.

Curry, Aaron B.↗