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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 1,387 records · Page 77
All sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Using space for technology development - Planning for the Space Station era

Experience with the Shuttle and free-flying satellites as technology test-beds has shown the feasibility and desirability of using space assets as a facility for technology development. Thus, by the time the Space Station era will have arrived, the technologist will be ready for an accessible engineering facility in space. As the 21st century is approached, it is expected that virtually every flight to the Space Station Freedom will be required to carry one or more research, technology, and engineering experiments. The experiments planned will utilize both the pressurized volume, and the external payload attachment facilities. A unique, but extremely important, class of experiments will use the Space Station itself as an experimental vehicle. Based upon recent examination of possible Space Station Freedom assembly sequences, technology payloads may well utilize 20-30 percent of available resources.

Ambrus, Judith H.↗
NASA NTRS1990

An online spacecraft environment interactions information system

This paper reviews the role that EnviroNET assumes as a contemporary system that scientists and engineers can use to share information on networks that are connected globally. Advantage is being taken to use this powerful communication tool for the space community to articulate the various anomalies that our space systems are experiencing. EnviroNET is being considered as a test bed for developing an expert system for diagnosing environmentally induced anomalies for spacecraft. The various offline activities in progress toward this objective are described.

Lauriente, Michael↗
NASA NTRS1989

Bioregenerative space and terrestrial habitat

For 15 years, NASA has been involved in bioregerative component development for air, water, and waste treatment. The results of this work have been integrated in the completion of a novel facility called BioHome which incorporates all of the developed bioregenerative components for air, water, and nutrient recovery into a single habitat. The evaluation and refinement of BioHome's integrated component efficiencies will provide a test-bed for future systems to be used in long-term space travel.

Wolverton, B. C.↗
NASA NTRS1989

Performance and modeling of the GSFC pointing acquisition and tracking system for laser communications

In this paper the NASA Goddard Space Flight Center (GSFC) laser communication pointing, acquisition, and tracking laboratory demonstration program is discussed. This program entails the construction of a flexible brass-board simulation tool, and a supporting computer simulation effort. The result of this program will be a viable test bed to support the design and specification of space-based laser communication terminals and, additionally, to address critical performance issues such as tracking robustness in the presence of background (e.g., stellar or earth) noise and/or internally generated thermal noise.

Fox, N. D.↗
NASA NTRS1989

Image understanding and the man-machine interface II; Proceedings of the Meeting, Los Angeles, CA, Jan. 17, 18, 1989

Image understanding concepts and models, image understanding systems and applications, advanced digital processors and software tools, and advanced man-machine interfaces are among the topics discussed. Particular papers are presented on such topics as neural networks for computer vision, object-based segmentation and color recognition in multispectral images, the application of image algebra to image measurement and feature extraction, and the integration of modeling and graphics to create an infrared signal processing test bed.

Barrett, Eamon B.↗
NASA NTRS1989

Initial characterization of a modular heat exchanger with an integral heat pipe

As part of the Civil Space Technology Initiative (CSTI) Advanced Technology program, a conceptual design of the Stirling space engibe (SSE) was generated to develop the technology base needed to meet the long duration, high capacity power requirements for future NASA space missions. The free-piston Stirling engine (FPSE) was chosen as the growth option in the CSTI program. An existing FPSE was modified as a test bed for a modular heat exchanger evaluation. Evaluation of the individual heat pipes before installation in the engine is described.

Schreiber, Jeffrey G.↗
NASA NTRS1990

An image recorded by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

The airborne visible/infrared imaging spectrometer (AVIRIS) is described, and an example of a false-color image recorded by this device is provided. The AVIRIS is capable of sensing in 209 visible and near-infrared wavebands with an 11km swath and a 20m spatial resolution. Evaluation flights for AVIRIS were made at an altitude of approximately 20km x 10.2km of low-lying and relatively flat irrigated land near Yuba City and Sacramento, California. Raw data were converted from digital numbers to radiance and radiometrically corrected at the NASA Jet Propulsion Laboratory. Notch filtering in the frequency domain of the image was used to remove periodic noise. The illustration of both spatial and spectral properties on the false-color image are explained. AVIRIS is designed to be flown in an ER-2 aircraft and will serve as a test-bed sensor for the High-Resolution Imaging Spectrometer (HIRIS) planned for the Earth Observing System.

Curran, Paul J.↗
NASA NTRS1990

Engine selection for the Space Exploration Initiative

The process used by NASA in the selection of the engine for the Space Exploration Initiative mission is described. The major propulsion requirements of the engine are addressed along with the engine options and key drivers and trades. Special attention is given to the requirements of the propellant feed system and the reaction control system. As a result of the 90-study, four moderate chamber pressure expander-cycle oxygen/hydrogen engines with a thrust level of 20,000 lbf each were selected for the lunar transfer vehicle. The paper also presents results of architecture studies and of advanced engine test bed studies.

Jones, Lee W.↗
NASA NTRS1991

Expert Script Generator

Program provides additional level of interface to facilitate use of telerobotic system. ESG (Expert Script Generator) is software package automatically generating high-level task objective commands from complex menu-driven language of the NASA Intelligent Systems Research Laboratory (ISRL). Makes telerobotics laboratory accessible to researchers not familiar with comprehensive language developed by ISRL for interacting with various systems of ISRL test bed. Incorporates expert-system technology to capture typical rules of operation that skilled operator uses. Result: operator interfact optimizing ability of system to perform task remotely in hazardous environment, in timely manner, and without undue stress to operator, while minimizing change for operator erros that damage equipment. Written in CLIPS.

Sliwa, Nancy E.↗
NASA NTRS1990

Heat flux measurement in SSME turbine blade tester

Surface heat flux values were measured in the turbine blade thermal cycling tester located at NASA-Marshall. This is the first time heat flux has been measured in a space shuttle main engine turbopump environment. Plots of transient and quasi-steady state heat flux data over a range of about 0 to 15 MW/sq m are presented. Data were obtained with a miniature heat flux gage device developed at NASA-Lewis. The results from these tests are being incorporated into turbine design models. Also, these gages are being considered for airfoil surface heat flux measurement on turbine vanes mounted in SSME turbopump test bed engine nozzles at Marshall. Heat flux effects that might be observed on degraded vanes are discussed.

Liebert, Curt H.↗
NASA NTRS1990

Intelligent Robotic Systems Study (IRSS), phase 2

Under the Intelligent Robotics System Study (IRSS) contract, a generalized robotic control architecture was developed for use with the ProtoFlight Manipulator Arm (PFMA). The controller built for the PFMA provides localized position based force control, teleoperation and advanced path recording and playback capabilities. Various hand controllers can be used with the system in conjunction with a synthetic time delay capability to provide a realistic test bed for typical satellite servicing tasks. The configuration of the IRSS system is illustrated and discussed. The PFMA has six computer controllable degrees of freedom (DOF) plus a seventh manually indexable DOF, making the manipulator a pseudo 7 DOF mechanism. Because the PFMA was not developed to operate in a gravity field, but rather in space, it is counter balanced at the shoulder, elbow and wrist and a spring counterbalance has been added near the wrist to provide additional support. Built with long slender intra-joint linkages, the PFMA has a workspace nearly 2 meters deep and possesses sufficient dexterity to perform numerous satellite servicing tasks. The manipulator is arranged in a shoulder-yaw, pitch, elbow-pitch, and wrist-pitch, yaw, roll configuration, with an indexable shoulder roll joint. Digital control of the PFMA is implemented using a variety of single board computers developed by Heurikon Corporation and other manufacturers. The IRSS controller is designed to be a multi-rate, multi-tasking system. Independent joint servos run at a 134 Hz rate and position based impedance control functions at 67 Hz. Autonomous path generation and hand controller inputs are processed at a 33 Hz.

Source record↗
NASA NTRS1990

Space station common module network topology and hardware development

Conceptual space station common module power management and distribution (SSM/PMAD) network layouts and detailed network evaluations were developed. Individual pieces of hardware to be developed for the SSM/PMAD test bed were identified. A technology assessment was developed to identify pieces of equipment requiring development effort. Equipment lists were developed from the previously selected network schematics. Additionally, functional requirements for the network equipment as well as other requirements which affected the suitability of specific items for use on the Space Station Program were identified. Assembly requirements were derived based on the SSM/PMAD developed requirements and on the selected SSM/PMAD network concepts. Basic requirements and simplified design block diagrams are included. DC remote power controllers were successfully integrated into the DC Marshall Space Flight Center breadboard. Two DC remote power controller (RPC) boards experienced mechanical failure of UES 706 stud-mounted diodes during mechanical installation of the boards into the system. These broken diodes caused input to output shorting of the RPC's. The UES 706 diodes were replaced on these RPC's which eliminated the problem. The DC RPC's as existing in the present breadboard configuration do not provide ground fault protection because the RPC was designed to only switch the hot side current. If ground fault protection were to be implemented, it would be necessary to design the system so the RPC switched both the hot and the return sides of power.

Anderson, P.↗
NASA NTRS1990

Utilization of the Spacehab module as a microgravity carrier

Spacehab Incorporated has proposed the use of its mid-deck augmentation module as a near term microgravity test bed. The orbital flight dynamics and payload accommodation capabilities of a Space Shuttle with the Spacehad module were investigated to assess this proposal. It was found that the module will provide a 1 microG (32.2 x 10(exp 6) ft/sq sec) quasi-steady state environment for limited periods of time when the shuttle is actively controlled. A passively stable attitude will provide a 4 microG environment for longer periods. Shuttle imposed constraints on the composite payload center of gravity, however, severely limit the possibilities for co-manifesting additional payloads. The analysis leading to those conclusions are detailed.

Sasamoto, Washito A.↗
NASA NTRS1990

Continuation of research into software for space operations support, volume 1

A prototype workstation executive called the Hardware Independent Software Development Environment (HISDE) was developed. Software technologies relevant to workstation executives were researched and evaluated and HISDE was used as a test bed for prototyping efforts. New X Windows software concepts and technology were introduced into workstation executives and related applications. The four research efforts performed included: (1) Research into the usability and efficiency of Motif (an X Windows based graphic user interface) which consisted of converting the existing Athena widget based HISDE user interface to Motif demonstrating the usability of Motif and providing insight into the level of effort required to translate an application from widget to another; (2) Prototype a real time data display widget which consisted of research methods for and prototyping the selected method of displaying textual values in an efficient manner; (3) X Windows performance evaluation which consisted of a series of performance measurements which demonstrated the ability of low level X Windows to display textural information; (4) Convert the Display Manager to X Window/Motif which is the application used by NASA for data display during operational mode.

Collier, Mark D.↗
NASA NTRS1990

Robot tracking system improvements and visual calibration of orbiter position for radiator inspection

The following separate topics are addressed: (1) improving a robotic tracking system; and (2) providing insights into orbiter position calibration for radiator inspection. The objective of the tracking system project was to provide the capability to track moving targets more accurately by adjusting parameters in the control system and implementing a predictive algorithm. A computer model was developed to emulate the tracking system. Using this model as a test bed, a self-tuning algorithm was developed to tune the system gains. The model yielded important findings concerning factors that affect the gains. The self-tuning algorithms will provide the concepts to write a program to automatically tune the gains in the real system. The section concerning orbiter position calibration provides a comparison to previous work that had been performed for plant growth. It provided the conceptualized routines required to visually determine the orbiter position and orientation. Furthermore, it identified the types of information which are required to flow between the robot controller and the vision system.

Tonkay, Gregory↗
NASA NTRS1991

Augmentation of the space station module power management and distribution breadboard

The space station module power management and distribution (SSM/PMAD) breadboard models power distribution and management, including scheduling, load prioritization, and a fault detection, identification, and recovery (FDIR) system within a Space Station Freedom habitation or laboratory module. This 120 VDC system is capable of distributing up to 30 kW of power among more than 25 loads. In addition to the power distribution hardware, the system includes computer control through a hierarchy of processes. The lowest level consists of fast, simple (from a computing standpoint) switchgear that is capable of quickly safing the system. At the next level are local load center processors, (LLP's) which execute load scheduling, perform redundant switching, and shed loads which use more than scheduled power. Above the LLP's are three cooperating artificial intelligence (AI) systems which manage load prioritizations, load scheduling, load shedding, and fault recovery and management. Recent upgrades to hardware and modifications to software at both the LLP and AI system levels promise a drastic increase in speed, a significant increase in functionality and reliability, and potential for further examination of advanced automation techniques. The background, SSM/PMAD, interface to the Lewis Research Center test bed, the large autonomous spacecraft electrical power system, and future plans are discussed.

Walls, Bryan↗
NASA NTRS1991

Advanced cryo propulsion systems

The following topics are presented in viewgraph form: (1) advanced space engine (ASE) chronology; (2) an ASE description; (3) a single expander; (4) a dual expander; (5) split expander; (6) launch vehicle start; (7) space start; (8) chemical transfer propulsion; and (9) an advanced expander test bed.

Tabata, William K.↗