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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 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
NASA NTRS2001

Space Station Human Factors: Designing a Human-Robot Interface

The experiments described in this paper are part of a larger joint MIT/NASA research effort and focus on the development of a methodology for designing and evaluating integrated interfaces for highly dexterous and multifunctional telerobot. Specifically, a telerobotic workstation is being designed for an Extravehicular Activity (EVA) anthropomorphic space station telerobot called Robonaut. Previous researchers have designed telerobotic workstations based upon performance of discrete subsets of tasks (for example, peg-in-hole, tracking, etc.) without regard for transitions that operators go through between tasks performed sequentially in the context of larger integrated tasks. The experiments presented here took an integrated approach to describing teleoperator performance and assessed how subjects operating a full-immersion telerobot perform during fine position and gross position tasks. In addition, a Robonaut simulation was also developed as part of this research effort, and experimentally tested against Robonaut itself to determine its utility. Results show that subject performance of teleoperated tasks using both Robonaut and the simulation are virtually identical, with no significant difference between the two. These results indicate that the simulation can be utilized as both a Robonaut training tool, and as a powerful design platform for telepresence displays and aids.

Rochlis, Jennifer L.↗
NASA NTRS2001

Integrated Design of a Telerobotic Workstation

The experiments described in this paper are part of a larger joint MIT/NASA research effort that focuses on the development of a methodology for designing and evaluating integrated interfaces for highly dexterous and multi-functional telerobots. Specifically, a telerobotic workstation is being designed for an Extravehicular Activity (EVA) anthropomorphic space station telerobot. Previous researchers have designed telerobotic workstations based upon performance of discrete subsets of tasks (for example, peg-in-hole, tracking, etc.) without regard for transitions that operators go through between tasks performed sequentially in the context of larger integrated tasks. The exploratory research experiments presented here took an integrated approach and assessed how subjects operating a full-immersion telerobot perform during the transitions between sub-tasks of two common EVA tasks. Preliminary results show that up to 30% of total task time is spent gaining and maintaining Situation Awareness (SA) of their task space and environment during transitions. Although task performance improves over the two trial days, the percentage of time spent on SA remains the same. This method identifies areas where workstation displays and feedback mechanisms are most needed to increase operator performance and decrease operator workload - areas that previous research methods have not been able to address.

Rochlis, Jennifer L.↗
NASA NTRS2012

A Peculiar Class of Debris Disks from Herschel/DUNES: A Steep Fall Off in the Far Infrared

Context. The existence of debris disks around old main sequence stars is usually explained by continuous replenishment of small dust grains through collisions from a reservoir of larger objects. Aims. We present photometric data of debris disks around HIP 103389 (HD199260), HIP 100350 (HN Peg, HD206860), and HIP 114948 (HD 219482), obtained in the context of our Herschel Open TIme Key Program DUNES (DUst around NEarby Stars). Methods. We used Herschel/PACS to detect the thermal emission of the three debris disks with a 30 sigma sensitivity of a few mJy at l00 micron and 160 micron. In addition, we obtained Herschel/PACS photometric data at 70 micron for HIP 103389. These observations are complemented by a large variety of optical to far-infrared photometric data. Two different approaches are applied to reduce the Herschel data to investigate the impact of data reduction on the photometry. We fit analytical models to the available spectral energy distribution (SED) data using the fitting method of simulated therma1 annealing as well as a classical grid search method. Results. The SEDs of the three disks potentially exhibit an unusually steep decrease at wavelengths >= 70 micron. We investigate the significance of the peculiar shape of these SEDs and the impact on models of the disks provided it is real. Using grain compositions that have been applied successfully for modeling of many other debris disks, our modeling reveals that such a steep decrease of the SEDs in the long wavelength regime is inconsistent with a power-law exponent of the grain size distribution -3.5 expected from a standard equilibrium collisional cascade. In contrast, a steep grain size distribution or, alternatively an upper grain size in the range of few tens of micrometers are implied. This suggests that a very distinct range of grain sizes would dominate the thermal. emission of such disks. However, we demonstrate that the understanding of the data of faint sources obtained with Herschel is still incomplete and that the significance of our results depends on the version of the data reduction pipeline used. Conclusions. A new mechanism to produce the dust in the presented debris disks, deviations from the conditions required for a standard equilibrium collisional cascade (grain size exponent of -3.5), and/or significantly different dust properties would be necessary to explain the potentially steep SED shape of the three debris disks presented.

Ertel, S.↗
NASA NTRS2014

Climate Forcing Datasets for Agricultural Modeling: Merged Products for Gap-Filling and Historical Climate Series Estimation

The AgMERRA and AgCFSR climate forcing datasets provide daily, high-resolution, continuous, meteorological series over the 1980-2010 period designed for applications examining the agricultural impacts of climate variability and climate change. These datasets combine daily resolution data from retrospective analyses (the Modern-Era Retrospective Analysis for Research and Applications, MERRA, and the Climate Forecast System Reanalysis, CFSR) with in situ and remotely-sensed observational datasets for temperature, precipitation, and solar radiation, leading to substantial reductions in bias in comparison to a network of 2324 agricultural-region stations from the Hadley Integrated Surface Dataset (HadISD). Results compare favorably against the original reanalyses as well as the leading climate forcing datasets (Princeton, WFD, WFD-EI, and GRASP), and AgMERRA distinguishes itself with substantially improved representation of daily precipitation distributions and extreme events owing to its use of the MERRA-Land dataset. These datasets also peg relative humidity to the maximum temperature time of day, allowing for more accurate representation of the diurnal cycle of near-surface moisture in agricultural models. AgMERRA and AgCFSR enable a number of ongoing investigations in the Agricultural Model Intercomparison and Improvement Project (AgMIP) and related research networks, and may be used to fill gaps in historical observations as well as a basis for the generation of future climate scenarios.

Climate Forcing Data↗
NASA NTRS2018

Antibacterial Activity of Silver-Graphene Quantum Dots Nanocomposites Against Gram-Positive and Gram-Negative Bacteria

The invention provides a composite of silver nanoparticles decorated with graphene quantum dots (Ag-GQDs) using pulsed laser synthesis. The nanocomposites were functionalized with polyethylene glycol (PEG). A concentration of 150 .mu.g/mL of Ag-GQDs, a non-toxic level for human cells, exhibits strong antibacterial activity against both Gram-Positive and Gram-Negative Bacteria.

Habiba, Khaled↗
NASA NTRSDate not supplied

Guidance Modifications and Enhancements for Space Launch System Block-1 in Support of Artemis I and Beyond

NASA is currently building the Space Launch System (SLS) Block-1 launch vehicle for the Artemis I test flight. Design of the Artemis II mission, which will use theBlock-1 vehicle to take astronauts around the moon for the first time in decades, is also underway. The Guidance, Navigation, and Controls (GN&C) algorithms will be largely similar for the two missions. However, the extensive simulation and testing campaign for Artemis I has revealed opportunities for improvements in the GN&C algorithms, allowing more effective use of the capabilities of the SLS vehicle, and enhancing safety for the astronauts aboard. This paper will de-scribe several planned algorithm updates for the Artemis II mission. The updates enhance the Powered Explicit Guidance (PEG) algorithm and auxiliary guidance algorithms.

Matt Hawkins↗
NASA NTRS2019

The Cognition and Fine Motor Skills Test Batteries: Normative Data and Interdependencies

Space mission success and safety relies upon astronaut functional state. Since spaceflight stressors affect cognitive processing and fine motor skills, NASA requires that measures of performance of these things remain within clinically accepted values (NASA STD 3001). NASA is in the process of developing two test batteries for the assessment of crew cognitive and fine motor skills before, during and after spaceflight. Toward that goal, the current project collected normative scores in 91 “astronaut-like” military and civilian pilots. The Cognition Test Battery (CTB) contains ten sub-tests that measure a range of cognitive abilities. For five of the ten CTB sub-tests, we propose scores to improve the battery’s sensitivity. Among the ten sub-tests, response times were more highly correlated than accuracy scores. Principle component analysis of the correlations revealed that the first response time factor could explain over 40% of the total variance and appeared to represent the tendency of observers to try to respond more quickly. The first accuracy factor (explaining only 20%) gave a high weight to the higher level cognitive sub-tests and a negative weight to tasks associated with motor and lower level cognitive processing. The Fine Motor Skills (FMS) test battery contains four sub-tests (Tracking, Pointing, Tracing, Rotating) performed on an Apple iPad tablet computer. Principle component analysis on the sub-test response time correlations revealed that the first two factors accounted for ~80% of the variance in performance. The first component captured overall speed on all four of the sub-tests. The second factor separated the sub-tasks into two groups (Drag-Point vs Trace-Rotate). Previous work found the first group response times correlated with that of a standard peg board task, while those of the other group did not. Correlations were computed between the first FMS factor and the response time and accuracy scores from each CTB sub-task. Performing fine motor behaviors rapidly was significantly correlated with the ability to perform many of the CTB sub-tests rapidly. This ability cannot be simple motor speed since scores on the Psychomotor Vigilance Test (PVT) subtask did not correlate with the ability to perform the other tasks rapidly. Speed on fine motor skills correlated significantly with accuracy on the short-term-memory sub-test. We hypothesize that eye movements, which can be regarded as a fine motor skill, may explain this relationship.

cognition↗
DOE OSTI2021

Bi-terminal pegylated integrin-binding peptides and methods of use thereof

The present invention provides bi-terminal PEGylated peptide conjugates that target an integrin such as αvβ6 integrin. In particular embodiments, the peptide conjugates of the present invention further comprise a biological agent such as an imaging agent or a therapeutic agent, e.g., covalently attached to one of the PEG moieties. The peptide conjugates of the present invention are particularly useful for imaging a tumor, organ, or tissue and for treating integrin-mediated diseases and disorders such as cancer, inflammatory diseases, autoimmune diseases, chronic fibrosis, chronic obstructive pulmonary disease (COPD), lung emphysema, and chronic wounding skin disease. Compositions and kits containing the peptide conjugates of the present invention find utility in a wide range of applications including, e.g., in vivo imaging and immunotherapy.

Hausner, Sven H.↗
DOE OSTI2021

Alpha(v)beta(6) integrin-binding peptides and methods of use thereof

The present invention provides peptide conjugates that target an integrin such as αvβ6 integrin. In particular embodiments, the peptide conjugates comprise a moiety such as a PEG moiety, an imaging agent, or a therapeutic agent. The peptide conjugates of the present invention are particularly useful for imaging a tumor, organ, or tissue. Compositions and kits containing the peptide conjugates of the present invention are also provided herein.

Tang, Yng↗
DOE OSTI2022

Bi-terminal pegylated integrin-binding peptides and methods of use thereof

The present invention provides bi-terminal PEGylated peptide conjugates that target an integrin such as αvβ6 integrin. In particular embodiments, the peptide conjugates of the present invention further comprise a biological agent such as an imaging agent or a therapeutic agent, e.g., covalently attached to one of the PEG moieties. The peptide conjugates of the present invention are particularly useful for imaging a tumor, organ, or tissue and for treating integrin-mediated diseases and disorders such as cancer, inflammatory diseases, autoimmune diseases, chronic fibrosis, chronic obstructive pulmonary disease (COPD), lung emphysema, and chronic wounding skin disease. Compositions and kits containing the peptide conjugates of the present invention find utility in a wide range of applications including, e.g., in vivo imaging and immunotherapy.

Hausner, Sven H.↗
DOE OSTI2024

Alpha(v)beta(6) integrin-binding peptides and methods of use thereof

The present invention provides peptide conjugates that target an integrin such as α v β 6 integrin. In particular embodiments, the peptide conjugates comprise a moiety such as a PEG moiety, an imaging agent, or a therapeutic agent. The peptide conjugates of the present invention are particularly useful for imaging a tumor, organ, or tissue. Compositions and kits containing the peptide conjugates of the present invention are also provided herein.

Tang, Yng↗
NASA NTRS1989

SSFP approach to software reuse

This talk began by presenting the Space Station Freedom Program (SSFP) definitions of software commonality and software reuse. Software commonality is the use of identical, interchangeable, functionally compatible, or similar software items to satisfy different sets of functionally similar requirements. The Software Support Environment (SSE) and the Data Management System (DMS) of onboard computing facilities are examples of SSFP common software. Software reuse is the use of identical, compatible, or similar software items in either modified or unmodified form to satisfy development activities at any point in the software life cycle; in other words, taking an existing item and applying it to another development activity. Software commonality has been mandated in several critical areas (such as the SSE and DMS) and a policy directive is under review. A software reuse study group was established in May 1988 to gather background information (see Level 2 Software Reuse Study that follows by Scott Herman). The SSFP Program Definition and Requirements Document contains requirements for SSE support in the area of software reuse. The SSE is a collection of tools and rules, and provides the common environment to be used for the life cycle management of all SSFP operational software.

Snyder, Peg↗
NASA NTRS1993

Ultrasonic inspection of a diffusion-bonded platelet rocket chamber liner

An ultrasonic inspection technique, which applies pulse-echo technology for examining the rocket chamber's liner-to-jacket interface was developed, which makes it possible to characterize disbonded layers in intimate contact. The method was used to inspect a simulated flat-geometry rocket chamber liner structure with debonded liner layers and to validate the use of boron nitride powder as a flaw introduction technique.

Matson, Douglas M.↗
NASA NTRS2014

Waveforms and Sonic Boom Perception and Response (WSPR): Low-Boom Community Response Program Pilot Test Design, Execution, and Analysis

The Waveforms and Sonic boom Perception and Response (WSPR) Program was designed to test and demonstrate the applicability and effectiveness of techniques to gather data relating human subjective response to multiple low-amplitude sonic booms. It was in essence a practice session for future wider scale testing on naive communities, using a purpose built low-boom demonstrator aircraft. The low-boom community response pilot experiment was conducted in California in November 2011. The WSPR team acquired sufficient data to assess and evaluate the effectiveness of the various physical and psychological data gathering techniques and analysis methods.

Page, Juliet A.↗