Results for “visualization in transportation” — Page 11

NASA NTRS2003

Solidification Using a Baffle in Sealed Ampoules (SUBSA)

Solidification Using a Baffle in Sealed Ampoules (SUBSA) will be the first materials science experiment conducted in the Microgravity Science Glovebox (MSG) Facility at the International Space Station (ISS) Alpha. The launch is schedule for May 31, 2002. Using the specially developed furnace, 10 Te and Zn-doped single crystals of InSb will be directionally solidified in microgravity. A key goal of the SUBSA investigation is to (i) clarify the origin of the melt motion in space laboratories and (ii) to reduce the magnitude of the melt motion to the point that it does not interfere with the transport phenomena. These goals will be accomplished through a special ampoule and furnace design. A disk-shaped baffle, positioned close to the freezing front, is used to reduce melt motion. Furthermore, the solidification will be visualized by using a transparent furnace, with a video camera, continuously sending images to the earth. This allows detection of bubbles and melt de-wetting that could cause surface tension driven convection. In preparation for the space experiments, 30 ground-based experiments were conducted. The results of ground based tests and numerical modeling will be presented. Based on numerical modeling, 12 mm 1D silica ampoules were selected. The small diameter ampoule favors closer placement of the baffle to the interface, without excessive radial segregation caused by forced convection while providing more damping of natural convection. The parts in the silica ampoule include 2 carbon springs made by Energy Science Laboratories, Inc., a pyrocarbon-coated graphite cylinder, pyrocarbon-coated graphite a baffle with the shaft and the InSb charge with the seed crystal grown by W.A. Bonner of Crystallod Inc.

Marin, C.↗

NASA NTRS2017

Synthetic Vision System Commercial Aircraft Flight Deck Display Technologies for Unusual Attitude Recovery

A Commercial Aviation Safety Team (CAST) study of 18 worldwide loss-of-control accidents and incidents determined that the lack of external visual references was associated with a flight crew's loss of attitude awareness or energy state awareness in 17 of these events. Therefore, CAST recommended development and implementation of virtual day-Visual Meteorological Condition (VMC) display systems, such as synthetic vision systems, which can promote flight crew attitude awareness similar to a day-VMC environment. This paper describes the results of a high-fidelity, large transport aircraft simulation experiment that evaluated virtual day-VMC displays and a "background attitude indicator" concept as an aid to pilots in recovery from unusual attitudes. Twelve commercial airline pilots performed multiple unusual attitude recoveries and both quantitative and qualitative dependent measures were collected. Experimental results and future research directions under this CAST initiative and the NASA "Technologies for Airplane State Awareness" research project are described.

Prinzel, Lawrence J., III↗

NASA NTRS1985

An innovative, multidisciplinary educational program in interactive information storage and retrieval. Presentation visuals

This Working Paper Series entry represents a collection of presentation visuals associated with the companion report entitled An Innovative, Multidisciplinary Educational Program in Interactive Information Storage and Retrieval, USL/DBMS NASA/RECON Working Paper Series report number DBMS.NASA/RECON-12. The project objectives are to develop a set of transportable, hands-on, data base management courses for science and engineering students to facilitate their utilization of information storage and retrieval programs.

Dominick, Wayne D.↗

NASA NTRS2003

The Results of a Simulator Study to Determine the Effects on Pilot Performance of Two Different Motion Cueing Algorithms and Various Delays, Compensated and Uncompensated

A study was conducted employing the Visual Motion Simulator (VMS) at the NASA Langley Research Center, Hampton, Virginia. This study compared two motion cueing algorithms, the NASA adaptive algorithm and a new optimal control based algorithm. Also, the study included the effects of transport delays and the compensation thereof. The delay compensation algorithm employed is one developed by Richard McFarland at NASA Ames Research Center. This paper reports on the analyses of the results of analyzing the experimental data collected from preliminary simulation tests. This series of tests was conducted to evaluate the protocols and the methodology of data analysis in preparation for more comprehensive tests which will be conducted during the spring of 2003. Therefore only three pilots were used. Nevertheless some useful results were obtained. The experimental conditions involved three maneuvers; a straight-in approach with a rotating wind vector, an offset approach with turbulence and gust, and a takeoff with and without an engine failure shortly after liftoff. For each of the maneuvers the two motion conditions were combined with four delay conditions (0, 50, 100 & 200ms), with and without compensation.

Guo, Li-Wen↗

NASA NTRS2004

Bi-Component Droplet Combustion in Reduced Gravity

This research deals with reduced-gravity combustion of bi-component droplets initially in the mm size range or larger. The primary objectives of the research are to study the effects of droplet internal flows, thermal and solutal Marangoni stresses, and species volatility differences on liquid species transport and overall combustion phenomena (e.g., gas-phase unsteadiness, burning rates, sooting, radiation, and extinction). The research program utilizes a reduced gravity environment so that buoyancy effects are rendered negligible. Use of large droplets also facilitates visualization of droplet internal flows, which is important for this research. In the experiments, droplets composed of low- and high-volatility species are burned. The low-volatility components are initially present in small amounts. As combustion of a droplet proceeds, the liquid surface mass fraction of the low-volatility component will increase with time, resulting in a sudden and temporary decrease in droplet burning rates as the droplet rapidly heats to temperatures close to the boiling point of the low-volatility component. This decrease in burning rates causes a sudden and temporary contraction of the flame. The decrease in burning rates and the flame contraction can be observed experimentally. Measurements of burning rates as well as the onset time for flame contraction allow effective liquid-phase species diffusivities to be calculated, e.g., using asymptotic theory. It is planned that droplet internal flows will be visualized in flight and ground-based experiments. In this way, effective liquid species diffusivities can be related to droplet internal flow characteristics. This program is a continuation of extensive ground-based experimental and theoretical research on bi-component droplet combustion that has been ongoing for several years. The focal point of this program is a flight experiment (Bi-Component Droplet Combustion Experiment, BCDCE). This flight experiment is under development. However, supporting ground-based studies have been performed. Some of the most recent ground-based research is summarized.

Shaw, Benjamin D.↗

NASA NTRSDate not supplied

The Viability of See and Avoid for Urban Air Mobility Operations

Urban Air Mobility (UAM) is an emerging aviation concept that could supplement today’s ground and air transportation systems. For UAM, it is generally assumed that the private sector will manage separation and not rely on the Federal Aviation Administration air traffic control system. To date, discussions of initial operations focus on using the visual abilities of the pilot to “see and avoid” (SAA) other aircraft. Decades of research on SAA has demonstrated that it is inadequate for reliable detection of aircraft that might pose a collision risk. The literature on multi-object tracking is also reviewed for findings on how well humans can visually track objects. The research shows that humans have limited resources for tracking and that this may be affected by object characteristics and cognitive skills. The conclusion is that SAA is a risky method for avoiding midair collisions. It is recommended that flight deck displays and automated collision avoidance systems be implemented for all UAM aircraft at the outset of their introduction.

urban air mobility↗

NASA NTRSDate not supplied

The Viability of See-and-Avoid for Midair Collision Avoidance for UAM

Urban Air Mobility (UAM) is an emerging aviation concept that could supplement today’s ground and air transportation systems. For UAM, it is generally assumed that the private sector will manage separation and not rely on the Federal Aviation Administration air traffic control system. To date, discussions of initial operations focus on using the visual abilities of the pilot to “see and avoid” (SAA) other aircraft. Decades of research on SAA has demonstrated that it is inadequate for reliable detection of aircraft that might pose a collision risk. The literature on multi-object tracking is also reviewed for findings on how well humans can visually track objects. The research shows that humans have limited resources for tracking and that this may be affected by object characteristics and cognitive skills. The conclusion is that SAA is a risky method for avoiding midair collisions. It is recommended that flight deck displays and automated collision avoidance systems be implemented for all UAM aircraft at the outset of their introduction.

urban air mobility↗

NASA NTRSDate not supplied

The Viability of See-and-Avoid for Midair Collision Avoidance for Urban Air Mobility (UAM)

Urban Air Mobility (UAM) is an emerging aviation concept that could supplement today’s ground and air transportation systems. For UAM, it is generally assumed that the private sector will manage separation and not rely on the Federal Aviation Administration air traffic control system. To date, discussions of initial operations focus on using the visual abilities of the pilot to “see and avoid” (SAA) other aircraft. Decades of research on SAA has demonstrated that it is inadequate for reliable detection of aircraft that might pose a collision risk. The literature on multi-object tracking is also reviewed for findings on how well humans can visually track objects. The research shows that humans have limited resources for tracking and that this may be affected by object characteristics and cognitive skills. The conclusion is that SAA is a risky method for avoiding midair collisions. It is recommended that flight deck displays and automated collision avoidance systems be implemented for all UAM aircraft at the outset of their introduction.

urban air mobility↗

NASA NTRS2023

The Viability of See-and-Avoid for Urban Air Mobility Operations

Urban Air Mobility (UAM) is an emerging aviation concept that could supplement today’s ground and air transportation systems. For UAM, it is generally assumed that the private sector will manage separation and not rely on the Federal Aviation Administration air traffic control system. To date, discussions of initial operations focus on using the visual abilities of the pilot to “see and avoid” (SAA) other aircraft. Decades of research on SAA has demonstrated that it is inadequate for reliable detection of aircraft that might pose a collision risk. The literature on multi-object tracking is also reviewed for findings on how well humans can visually track objects. The research shows that humans have limited resources for tracking and that this may be affected by object characteristics and cognitive skills. The conclusion is that SAA is a risky method for avoiding midair collisions. It is recommended that flight deck displays and automated collision avoidance systems be implemented for all UAM aircraft at the outset of their introduction.

urban air mobility↗

NASA NTRS1984

TAC BRAWLER - An application of engagement simulation modeling to simulator visual system display requirements for air combat maneuvering

The TAC BRAWLER air combat simulation models both the acquisition and use of visual information by the pilot. It was used to provide the designers of manned simulators for air-to-air combat with information regarding the training implications of display system resolution, inherent target contrast, field of view, and transport delay. Various display designs were simulated, and the resulting quantitative and qualitative differences in engagements were considered indicators of possible mistraining. Display resolution was found to alter combats primarily through its effect on detection ranges; the 'pixel averaging' contrast management technique was shown to largely compensate for this problem. Transport delay significantly degrades pilot tracking ability, but the training impact of the effect is unclear.

Kerchner, R. M.↗

NASA NTRS1999

Combustion of Two-Component Miscible Droplets in Reduced Gravity

This paper presents recent theoretical and experimental results from an ongoing research program that deals with reduced-gravity combustion of bi-component droplets initially in the mm size range or larger. The primary objectives of the research are to study the effects of droplet internal flows, thermal and solutal Marangoni stresses, and species volatility differences on liquid species transport and overall combustion phenomena (e.g., gas-phase unsteadiness, burning rates, sooting, radiation, and extinction). The research program utilizes a reduced-gravity environment so that buoyancy effects are rendered negligible. Use of large droplets also facilitates visualization of droplet internal flows, which is important to this research. This program is a continuation of extensive ground based experimental and theoretical research on bi-component droplet combustion which has been ongoing for several years. The focal point of this research program is a flight experiment (Bi-Component Droplet Combustion Experiment, BCDCE). This flight experiment is still under development. However, supporting ground studies have been performed, and preliminary data have been obtained from flight experiments (Fiber Supported Droplet Combustion Experiment, FSDC-1 and FSDC-2). These flight experiments were performed during the STS-73/USML-2 and STS-94/MSL- I missions. In the experiments, droplets composed of low- and high-volatility species are burned. The low-volatility components are initially present in small amounts. As combustion of a droplet proceeds, the liquid surface mass fraction of the low-volatility component will increase with time, resulting in a sudden and temporary decrease in droplet burning rates as the droplet rapidly heats to temperatures close to the boiling point of the low-volatility component. This decrease in burning rates causes a sudden and temporary contraction of the flame. The decrease in burning rates and the flame contraction can be observed experimentally. Measurements of burning rates as well as the onset time for flame contraction allow effective liquid-phase species diffusivities to be calculated, e.g., using asymptotic theory. A goal of the research is to relate effective liquid species diffusivities to droplet internal flow characteristics. Droplet internal flows will be visualized in future flight and ground-based experiments.

Shaw, B. D.↗

NASA NTRS2001

Bi-Component Droplet Combustion in Reduced Gravity

This research deals with reduced-gravity combustion of bi-component droplets initially in the mm size range or larger. The primary objectives of the research are to study the effects of droplet internal flows, thermal and solutal Marangoni stresses, and species volatility differences on liquid species transport and overall combustion phenomena (e.g., gas-phase unsteadiness, burning rates, sooting, radiation, and extinction). The research program utilizes a reduced-gravity environment so that buoyancy effects are rendered negligible. Use of large droplets also facilitates visualization of droplet internal flows, which is important for this research. In the experiments, droplets composed of low- and high-volatility species are burned. The low-volatility components are initially present in small amounts. As combustion of a droplet proceeds, the liquid surface mass fraction of the low-volatility component will increase with time, resulting in a sudden and temporary decrease in droplet burning rates as the droplet rapidly heats to temperatures close to the boiling point of the low-volatility component. This decrease in burning rates causes a sudden and temporary contraction of the flame. The decrease in burning rates and the flame contraction can be observed experimentally. Measurements of burning rates as well as the onset time for flame contraction allow effective liquid-phase species diffusivities to be calculated, e.g., using asymptotic theory. It is planned that droplet internal flows will be visualized in future flight and ground-based experiments. In this way, effective liquid species diffusivities can be related to droplet internal flow characteristics. This program is a continuation of extensive ground based experimental and theoretical research on bi-component droplet combustion that has been ongoing for several years. The focal point of this program is a flight experiment (Bi-Component Droplet Combustion Experiment, BCDCE). This flight experiment is under development. However, supporting studies have been performed. Because of space limitations, only some of the research performed over the last two years (since the 5th Microgravity Combustion Workshop) is summarized here.

Shaw, B. D.↗

NASA NTRS2003

Bi-Component Droplet Combustion in Reduced Gravity

This research deals with reduced-gravity combustion of bi-component droplets initially in the mm size range or larger. The primary objectives of the research are to study the effects of droplet internal flows, thermal and solutal Marangoni stresses, and species volatility differences on liquid species transport and overall combustion phenomena (e.g., gas-phase unsteadiness, burning rates, sooting, radiation, and extinction). The research program utilizes a reduced-gravity environment so that buoyancy effects are rendered negligible. Use of large droplets also facilitates visualization of droplet internal flows, which is important for this research. In the experiments, droplets composed of low- and high-volatility species are burned. The low-volatility components are initially present in small amounts. As combustion of a droplet proceeds, the liquid surface mass fraction of the low-volatility component will increase with time, resulting in a sudden and temporary decrease in droplet burning rates as the droplet rapidly heats to temperatures close to the boiling point of the low-volatility component. This decrease in burning rates causes a sudden and temporary contraction of the flame. The decrease in burning rates and the flame contraction can be observed experimentally. Measurements of burning rates as well as the onset time for flame contraction allow effective liquid-phase species diffusivities to be calculated, e.g., using asymptotic theory. It is planned that droplet internal flows will be visualized in flight and ground-based experiments. In this way, effective liquid species diffusivities can be related to droplet internal flow characteristics. This program is a continuation of extensive ground based experimental and theoretical research on bi-component droplet combustion that has been ongoing for several years. The focal point of this program is a flight experiment (Bi-Component Droplet Combustion Experiment, BCDCE). This flight experiment is under development. However, supporting ground-based studies have been performed. This ground-based research is summarized below.

Shaw, B. D.↗

NASA NTRS2002

Visualization of particle flux in the human body on the surface of Mars

For a given galactic cosmic ray (GCR) environment, information on the particle flux of protons, alpha particles, and heavy ions, that varies with respect to the topographical altitude on the Martian surface, are needed for planning exploration missions to Mars. The Mars Global Surveyor (MGS) mission with its Mars Orbiter Laser Altimeter (MOLA) instrument has been providing precise topographical surface map of the Mars. With this topographical data, the particle flux at the Martian surface level through the CO2 atmospheric shielding for solar minimum and solar maximum conditions are calculated. These particle flux calculations are then transported first through an anticipated shielding of a conceptual shelter with several water equivalent shield values (up to 50 g/cm2 of water in steps of 5 g/cm2) considered to represent a surface habitat, and then into the human body. Model calculations are accomplished utilizing the HZETRN, QMSFRG, and SUM-MARS codes. Particle flux calculations for 12 different locations in the human body were considered from skin depth to the internal organs including the blood-forming organs (BFO). Visualization of particle flux in the human body at different altitudes on the Martian surface behind a known shielding is anticipated to provide guidance for assessing radiation environment risk on the Martian surface for future human missions.

NASA Center JSC↗

NASA NTRS1979

Convective flow during dendritic growth

A review is presented of the major experimental findings obtained from recent ground-based research conducted under the SPAR program. Measurements of dendritic growth at small supercoolings indicate that below approximately 1.5 K a transition occurs from diffusive control to convective control in succinonitrile, a model system chosen for this study. The key theoretical ideas concerning diffusive and convective heat transport during dendritic growth are discussed, and it is shown that a transition in the transport control should occur when the characteristic length for diffusion becomes larger than the characteristic length for convection. The experimental findings and the theoretical ideas discussed suggest that the Fluid Experiment System could provide appropriate experimental diagnostics for flow field visualization and quantification of the fluid dynamical effects presented here.

Glicksman, M. E.↗

NASA NTRS1988

NLF technology is ready to go

Natural laminar flow (NLF) can reduce drag on aircraft developed using modern structural design methods. Modern metal and composite construction methods can meet NLF requirements for subsonic commuter and business airframes. NLF research at NASA concentrates on expanding the practical application of NLF drag reduction technology; payoffs include progress with liquid-crystal flow visualization, NLF on three-dimensional bodies, and the effects of acoustics on laminar stability. Fuel savings from 2 to 4 percent are expected if laminar flow could be achieved over the forward 50 percent of engine nacelles on large transports depending on the configuration. It is concluded that the skill required to use NLF for drag reduction depends on understanding the conservative design corridors within which laminar flow is durable and reliable.

Holmes, Bruce J.↗

NASA NTRS1997

Debris/Ice/TPS Assessment and Integrated Photographic Analysis of Shuttle Mission STS-80

A debris/ice/thermal protection system (TPS) assessment and integrated photographic analysis was conducted for Shuttle mission STS-80. Debris inspections of the flight elements and launch pad were performed before and after launch. Icing conditions on the External Tank were assessed by the use of computer programs and infrared scanned data during cryogenic loading of the vehicle, followed by on-pad visual inspection. High speed photography of the launch was analyzed to identify ice/debris sources and evaluate potential vehicle damage and/or in-flight anomalies. This report documents the ice/debris/thermal protection system conditions and integrated photographic analysis of Shuttle mission Space Transportation System (STS-80) and the resulting effect on the Space Shuttle Program.

Katnik, Gregory N.↗

NASA NTRS1999

Investigation of Wake-Vortex Aircraft Encounters

The National Aeronautics and Space Administration is addressing airport capacity enhancements during instrument meteorological conditions though the Terminal Area Productivity (TAP) program. The major goal of the TAP program is to develop the technology that will allow air traffic levels during instrument meteorological condition to approach those achieved during visual operations. The Reduced Spacing Operations (RSO) subelement of TAP at the NASA Langley Research Center (LaRC) will develop the Aircraft Vortex Spacing System (AVOSS). The purpose of the AVOSS is to integrate current and predicted weather conditions, wake vortex transport and decay knowledge, wake vortex sensor data, and operational definitions of acceptable strengths for vortex encounters to produce dynamic wake vortex separation criteria. The proposed research is in support of the wake vortex hazard definition component of the LaRC AVOSS development research. The research program described in the next section provided an analysis of the static test data and uses this data to evaluate the accuracy vortex/wake-encounter models. The accuracy of these models has not before been evaluated using experimental data. The research results also presented the first analysis of the forces and moments imparted on an airplane during a wake vortex encounter using actual flight test data.

Smith, Sonya T.↗