SEARCH · Engineering Papers
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.
The use of Rockwell experiences to assist NASA/Ames with planning for space station mockup studies is outlined. Mockup lessons from Rockwell spacecraft studies are reviewed. Typical and unique mockup technology applications are illustrated. Potential uses for space station mockups are given along with the areas of concern. Workstation design requirements are given.
Two rotary balance apparatuses were developed for testing airplane models in a coning motion. A large scale apparatus, developed for use in the 12-Foot Pressure Wind tunnel primarily to permit testing at high Reynolds numbers, was recently used to investigate the aerodynamics of 0.05-scale model of the F-15 fighter aircraft. Effects of Reynolds number, spin rate parameter, model attitude, presence of a nose boom, and model/sting mounting angle were investigated. A smaller apparatus, which investigates the aerodynamics of bodies of revolution in a coning motion, was used in the 6-by-6 foot Supersonic Wind Tunnel to investigate the aerodynamic behavior of a simple representation of a modern fighter, the Standard Dynamic Model (SDM). Effects of spin rate parameter and model attitude were investigated. A description of the two rigs and a discussion of some of the results obtained in the respective test are presented.
Two rotary balance apparatuses were developed for testing airplane models in a coning motion. A large scale apparatus, developed for use in the 12-foot Pressure Wind Tunnel primarily to permit testing at high Reynolds numbers, was recently used to investigate the aerodynamics of 0.05-scale model of the F-15 fighter aircraft. Effects of Reynolds number, spin rate parameter, model attitude, presence of a nose boom, and model/sting mounting angle were investigated. A smaller apparatus, which investigates the aerodynamics of bodies of revolution in a coning motion, was used in the 6-by-6 foot Supersonic Wind Tunnel to investigate the aerodynamic behavior of a simple representation of a modern fighter, the Standard Dynamic Model (SDM). Effects of spin rate parameter and model attitude were investigated. A description of the two rigs and a discussion of some of the results obtained in the respective tests are presented.
Software inspections are a set of formal technical review procedures held at selected key points during software development in order to find defects in software documents--is described in terms of history, participants, tools, procedures, statistics, and database analysis.
Engineering and biological data gathered with the research animal holding facilities (RAHFs) used on the Spacelab 3 mission are summarized. The animals totaled 24 rats and two squirrel monkeys. The RAHFs included biotelemetry, cameras and environmental monitoring equipment. The primary mission goal was engineering evaluation of the RAHFs and ancillary equipment. Tightly-fitted seals were found to be a necessity for keeping waste and food particles from contaminating the Spacelab equipment. All the rats returned with little muscle tone and suppressed immune systems. The monkeys displayed highly individual responses to spaceflight. Both species exhibited reduced abilities to maintain meticulously clean furs in weightlessness. Details of several physiological changes detected during post-flight autopsies are provided.
A hardware description and experimental results are reported from the initial STS flight carrying two Research Animal Holding Facility (RAHF) units. The flight was mainly intended for engineering check-out of the RAHF design. The system development and prelaunch preparations are briefly summarized, including the provisions of retrieval teams at alternate landing sites and extensive rehearsals to ensure timely data analysis. The flight revealed a problem with the containment of particulates from the RAHFs and the provision of adequate water for the monkeys. On-board films showed that one of the monkeys experienced motion sickness, from which he recovered after 5 days in space. Necropsy of the subject rats documented suppressed interferon production, loss of muscle mass, an up to 13 percent loss in bone mass (after a one week flight), and a 20 percent decrease in growth-inducing hormone. The volume of data collected is thought to exceed the combined data gathered on all previous U.S. space missions.
An obvious extension of wind tunnel laser Doppler velocimetry (LDV), which is currently mainly limited to two-component measurements, would involve the measurement of three simultaneous velocity components. The present paper is concerned with an approach to reduce the degree of optical complexity involved in the design of a three-dimensional (3D) LDV system, taking into account the use of polarization separation. Such a system, utilizing polarization as well as color separation, has been designed and tested in a 6 x 6 foot supersonic wind tunnel. The considered instrument was designed for the on line measurement of three mean velocity components, turbulence levels, and shear stresses on a number of models under a wide variety of test conditions. Attention is given to optical details, data reduction, and sample application.
Explore the source record for details and available documents.
Flow-field measurements have been made to determine the effects of core blowing on vortex breakdown and control. The results of these proof-of-concept experiments clearly demonstrate the usefulness of water tunnels as test platforms for advanced flow-field simulation and measurement.
The features of a 1/50-scale model of the National Full-Scale Aerodynamics Complex are first described. An overview is then given of some results from the various tests conducted with the model to aid in the design of the full-scale facility. It was found that the model tunnel simulated accurately many of the operational characteristics of the full-scale circuits. Some characteristics predicted by the model were, however, noted to differ from previous full-scale results by about 10%.
The purpose of the workshop was to discuss the current technology base for aerodynamic ground effects and to establish directions for further research of advanced, high performance aircraft designs, particularly those concepts utilizing powered lift systems; e.g., V/STOL, ASTOVL, and STOL aircraft. Fourteen papers were presented in the following areas: suckdown and fountain effects in hover; STOL ground vortex and hot gas ingestion; and vortex lift and jet flaps in ground effect. These subject areas were chosen with regard to current activities in the field of aircraft ground effects research.
Means for evaluating data bus architectures and protocols for highly integrated flight control system applications are needed. Described are the criteria and plans to do this by using the NASA/Ames Intelligent Redundant Actuation System (IRAS) experimental set-up. Candidate bus architectures differ from one another in terms of: topology, access control, message transfer schemes, message characteristics, initialization. data flow control, transmission rates, fault tolerance, and time synchronization. The evaluation criteria are developed relative to these features. A preliminary, analytical evaluation of four candidate busses (MIL-STD-1553B, DATAC, Ethernet, and HSIS) is described. A bus must be exercised in a real-time environment to evaluate its dynamic characteristics. A plan for real-time evaluation of these four busses using a combination of hardware and simulation techniques is presented.
Flow-field measurements have been made to determine the effects of core blowing on vortex breakdown and control. The results of these proof-of-concept experiments clearly demonstrate the usefulness of water tunnels as test platforms for advanced flow-field simulation and measurement.
Research has been underway for several years to develop valid and reliable measures and predictors of workload as a function of operator state, task requirements, and system resources. Although the initial focus of this research was on aeronautics, the underlying principles and methodologies are equally applicable to space, and provide a set of tools that NASA and its contractors can use to evaluate design alternatives from the perspective of the astronauts. Objectives and approach of the research program are described, as well as the resources used in conducting research and the conceptual framework around which the program evolved. Next, standardized tasks are described, in addition to predictive models and assessment techniques and their application to the space program. Finally, some of the operational applications of these tasks and measures are reviewed.
Engineering enrollments are rising in universities; however the graduate engineering shortage continues. Particularly, women and minorities will be underrepresented for many years. As one means of solving this shortage, Federal agencies facing future scientific and technological challenges were asked to participate in the Summer High School Apprenticeship Research Program (SHARP). This program was created to provide an engineering experience for gifted female and minority high school students at an age when they could still make career and education decisions. The SHARP program is designed for high school juniors who are U.S. citizens, are 16 years old, and who have very high promise in math and science through outstanding academic performance in high school. Students who are accepted into this summer program will earn as they learn by working 8 hr days in a 5-day work week. Reports from SHARP students are presented.
A computer network can benefit the user by making his/her work quicker and easier. A computer network is made up of seven different layers with the lowest being the hardware, the top being the user, and the middle being the software. These layers are discussed.
A major goal of the reseach group is to develop mathematical and computational models of early human vision. These models are valuable in the prediction of human performance, in the design of visual coding schemes and displays, and in robotic vision. To date researchers have models of retinal sampling, spatial processing in visual cortex, contrast sensitivity, and motion processing. Based on their models of early human vision, researchers developed several schemes for efficient coding and compression of monochrome and color images. These are pyramid schemes that decompose the image into features that vary in location, size, orientation, and phase. To determine the perceptual fidelity of these codes, researchers developed novel human testing methods that have received considerable attention in the research community. Researchers constructed models of human visual motion processing based on physiological and psychophysical data, and have tested these models through simulation and human experiments. They also explored the application of these biological algorithms to applications in automated guidance of rotorcraft and autonomous landing of spacecraft. Researchers developed networks for inhomogeneous image sampling, for pyramid coding of images, for automatic geometrical correction of disordered samples, and for removal of motion artifacts from unstable cameras.
The research projects planned for the Life Sciences program have a goal of answering basic questions concerning the nature of life itself and its evolution in the universe from basic elements, as well as the search for extraterrestrial intelligence. The program also includes studies of the evolution and development of life on the planet earth, and the global changes occurring today that affect life on the earth. The paper describes the simulation models developed to study the effects of space, the flight projects of the program, and the biomedical program, which currently focuses on the physiological changes in the human body that are associated with space flights and the interactions among these changes.