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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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS2006

Two Years of Chemical Sampling on Meridiani Planum by the Alpha Particle X-Ray Spectrometer Onboard the Mars Exploration Rover Opportunity

For over two terrestrial years, the Mars Exploration Rover Opportunity has been exploring the martian surface at Meridiani Planum using the Athena instrument payload [1], including the Alpha Particle X-Ray Spectrometer (APXS). The APXS has a small sensor head that is mounted on the robotic arm of the rover. The chemistry, mineralogy and morphology of selected samples were investigated by the APXS along with the Moessbauer Spectrometer (MB) and the Microscopic Imager (MI). The Rock Abrasion Tool (RAT) provided the possibility to dust and/or abrade rock surfaces down to several millimeters to expose fresh material for analysis. We report here on APXS data gathered along the nearly 6-kilometers long traverse in craters and plains of Meridiani.

Bruckner, J.↗
NASA NTRS2012

Active Piezoelectric Vibration Control of Subscale Composite Fan Blades

As part of the Fundamental Aeronautics program, researchers at NASA Glenn Research Center (GRC) are investigating new technologies supporting the development of lighter, quieter, and more efficient fans for turbomachinery applications. High performance fan blades designed to achieve such goals will be subjected to higher levels of aerodynamic excitations which could lead to more serious and complex vibration problems. Piezoelectric materials have been proposed as a means of decreasing engine blade vibration either through a passive damping scheme, or as part of an active vibration control system. For polymer matrix fiber composite blades, the piezoelectric elements could be embedded within the blade material, protecting the brittle piezoceramic material from the airflow and from debris. To investigate this idea, spin testing was performed on two General Electric Aviation (GE) subscale composite fan blades in the NASA GRC Dynamic Spin Rig Facility. The first bending mode (1B) was targeted for vibration control. Because these subscale blades are very thin, the piezoelectric material was surface-mounted on the blades. Three thin piezoelectric patches were applied to each blade two actuator patches and one small sensor patch. These flexible macro-fiber-composite patches were placed in a location of high resonant strain for the 1B mode. The blades were tested up to 5000 rpm, with patches used as sensors, as excitation for the blade, and as part of open- and closed-loop vibration control. Results show that with a single actuator patch, active vibration control causes the damping ratio to increase from a baseline of 0.3% critical damping to about 1.0% damping at 0 RPM. As the rotor speed approaches 5000 RPM, the actively controlled blade damping ratio decreases to about 0.5% damping. This occurs primarily because of centrifugal blade stiffening, and can be observed by the decrease in the generalized electromechanical coupling with rotor speed.

Duffy, Kirsten P.↗
NASA NTRS2015

Feasibility Assessment of an EVA Glove Sensing Platform to Evaluate Potential Hand Injury Risk Factors

Injuries to the hands are common among astronauts who train for extravehicular activity (EVA). When the gloves are pressurized, they restrict movement and create pressure points during tasks, sometimes resulting in pain, muscle fatigue, abrasions, and occasionally more severe injuries such as onycholysis. A brief review of the Lifetime Surveillance of Astronaut Health's injury database reveals that 58% of total astronaut hand and arm injuries from NBL training between 1993 and 2010 occurred either to the fingernail, MCP, or fingertip. The purpose of this study was to assess the potential of using small sensors to measure force acting on the fingers and hand within pressurized gloves and other variables such as blood perfusion, skin temperature, humidity, fingernail strain, skin moisture, among others. Tasks were performed gloved and ungloved in a pressurizable glove box. The test demonstrated that fingernails saw greater transverse strain levels for tension or compression than for longitudinal strain, even during axial fingertip loading. Blood perfusion peaked and dropped as the finger deformed during finger presses, indicating an initial dispersion and decrease of blood perfusion levels. Force sensitive resistors to force plate comparisons showed similar force curve patterns as fingers were depressed, indicating suitable functionality for future testing. Strategies for proper placement and protection of these sensors for ideal data collection and longevity through the test session were developed and will be implemented going forward for future testing.

Reid, Christopher R.↗
NASA NTRS2016

Analysis of Potential Glove-Induced Hand Injury Metrics During Typical Neutral Buoyancy Training Operations

Injuries to the hands are common among astronauts who train for extravehicular activity. When the gloves are pressurized, they restrict movement and create pressure points during tasks, sometimes resulting in pain, muscle fatigue, abrasions, and occasionally more severe injuries such as onycholysis. A brief review of NASA's Lifetime Surveillance of Astronaut Health's injury database reveals that 76 percent of astronaut hand and arm injuries from training between 1993 and 2010 occurred either to the fingernail, finger crotch, metacarpophalangeal joint, or fingertip. The purpose of this study was to assess the potential of using small sensors to measure forces acting on the fingers and hand within pressurized gloves and other variables such as skin temperature, humidity, and fingernail strain of a NASA crewmember during typical NBL (Neutral Buoyancy Laboratory) training activity. During the 5-hour exercise, the crewmember seemed to exhibit very large forces on some fingers, resulting in higher strain than seen in previous glove-box testing. In addition, vital information was collected on the glove cavity environment with respect to temperature and humidity. All of this information gathered during testing will be carried forward into future testing, potentially in glove-box- or 1G- (1 gravitational force) or NBL-suited environments, to better characterize and understand the possible causes of hand injury amongst NASA crew.

McFarland, Shane↗
NASA NTRS2019

Characterizing Spatio-Temporal Ozone Gradients Along Coastal Boundaries: Sondes and Mobile Measurements from OWLETS-2

One of the major difficulties for the modeling and satellite communities is the validation of O3 levels in sharp coastal transition regions within metropolitan areas. Land-water gradients of ozone as well as its precursors can be significant due to differences in emissions, land use, surface deposition, boundary layer height, and mesoscale wind patterns. The Ozone Water-Land Environmental Transition Study (OWLETS-2) was a follow-on field campaign spearheaded by NASA GSFC and LaRC's Tropospheric Ozone Lidar Network (TOLnet) conducted in the summer of 2018 within the Upper Chesapeake region to better characterize spatial and vertical distribution of various pollutants across the coastal boundary. Supporting this campaign, 40 ozonesondes were simultaneously launched directly in the marine environment on Hart Miller Island (HMI) and on two land sites: both the University of Maryland, Baltimore County (UMBC) and Howard University-Beltsville (HUBV). In addition, Personal Ozone Monitors (POMs) - small sensors - were deployed in a variety of environments - car, boat, and drone, to name a few - to quantify ozone across fine spatial and temporal thresholds. The purpose of these measurements is multifaceted: to provide both ozone pollution information to coastal metropolitan communities and validation to satellite, modeling, and forecasting communities, especially in current and future satellite endeavors such as TROPOMI and TEMPO.

coastal pollution↗
NASA NTRS2018

TPSAS-NF1676L-30290-DND

The Summer 2017 Ozone Water Land Environmental Transition Study (OWLETS) mission set out to compare the differences in ozone concentrations between inland measurements of air quality, specifically at Langley Research Center (LaRC), and measurements taken over water, specifically on the Chesapeake Bay Bridge Tunnel (CBBT), as well as the vertical profiles above each location. Current weather models often predict a gradient in ozone concentration between land and ocean and this campaign attempted to capture this difference using hand-held Personal Ozone Monitors (POMs) in correspondence to ozonesondes and LIDAR measurements. The Tropospheric Emissions: Monitoring of Pollution (TEMPO) is the first geostationary satellite that will take hourly measurements to monitor air pollutants across North America using solar backscatter. The small footprint allows for higher spatial resolution readings of many parameters including O3, NO2 , and aerosol. TEMPO’s higher resolution readings would benefit from validation techniques on the ground. Validation methods usually include comparison to air quality monitoring stations, but they could also incorporate other forms of validation such as comparison to small sensors. In cooperation with TEMPO, OWLETS aims to provide the user community high resolution temporal and spatial, both horizontal and vertical, variability of O3 simultaneously over the land and water during various air quality events to improve forecast models and air quality satellite retrievals. Together, these missions will improve spatial resolution and capture temporal variability of air quality over North America.

Emily Gargulinski↗
NASA NTRS2017

TPSAS-NF1676L-28489-DND

This presentation describes the integration of small sensor systems with sUAS vehicles that will better quantify emissions from hard-to-sample area sources, introduces current capabilities, highlights recent OWLETS missions, and discusses future campaigns.

Edward E Adcock↗
NASA NTRS2017

Multi-Source Sensor Fusion for Small Unmanned Aircraft Systems Using Fuzzy Logic

As the applications for using small Unmanned Aircraft Systems (sUAS) beyond visual line of sight (BVLOS) continue to grow in the coming years, it is imperative that intelligent sensor fusion techniques be explored. In BVLOS scenarios the vehicle position must accurately be tracked over time to ensure no two vehicles collide with one another, no vehicle crashes into surrounding structures, and to identify off-nominal scenarios. Therefore, in this study an intelligent systems approach is used to estimate the position of sUAS given a variety of sensor platforms, including, GPS, radar, and on-board detection hardware. Common research challenges include, asynchronous sensor rates and sensor reliability. In an effort to realize these challenges, techniques such as a Maximum a Posteriori estimation and a Fuzzy Logic based sensor confidence determination are used.

fuzzy logic↗
NASA NTRS2017

Multi-Source Sensor Fusion for Small Unmanned Aircraft Systems Using Fuzzy Logic

As the applications for using small Unmanned Aircraft Systems (sUAS) beyond visual line of sight (BVLOS) continue to grow in the coming years, it is imperative that intelligent sensor fusion techniques be explored. In BVLOS scenarios the vehicle position must accurately be tracked over time to ensure no two vehicles collide with one another, no vehicle crashes into surrounding structures, and to identify off-nominal scenarios. Therefore, in this study an intelligent systems approach is used to estimate the position of sUAS given a variety of sensor platforms, including, GPS, radar, and on-board detection hardware. Common research challenges include, asynchronous sensor rates and sensor reliability. In an effort to realize these challenges, techniques such as a Maximum a Posteriori estimation and a Fuzzy Logic based sensor confidence determination are used.

UAS↗
NASA NTRS1981

Small conductive particle sensor

An electrostatic conductive fiber detector is disclosed for use in detecting, counting and measuring the length of fibers down to 0.1 mm and below with increased accuracy and reliability over prior art devices. It can be used for detection of fibers suspending in a flowing gas, in a nonflowing gas, or in a vacuum and its accumulated counts over a period of time is essentially unaffected by velocity of the fibers being detected.

Taback, I.↗
NASA NTRS2007

A Small Angle Scattering Sensor System for the Characterization of Combustion Generated Particulate

One of the critical issues for the US space program is fire safety of the space station and future launch vehicles. A detailed understanding of the scattering signatures of particulate is essential for the development of a false alarm free fire detection system. This paper describes advanced optical instrumentation developed and applied for fire detection. The system is being designed to determine four important physical properties of disperse fractal aggregates and particulates including size distribution, number density, refractive indices, and fractal dimension. Combustion generated particulate are the primary detection target; however, in order to discriminate from other particulate, non-combustion generated particles should also be characterized. The angular scattering signature is measured and analyzed using two photon optical laser scattering. The Rayleigh-Debye-Gans (R-D-G) scattering theory for disperse fractal aggregates is utilized. The system consists of a pulsed laser module, detection module and data acquisition system and software to analyze the signals. The theory and applications are described.

Feikema, Douglas A.↗
NASA NTRSDate not supplied

Sweating the Small Stuff: A Sensor for Real-Time Neuro-Immune Axis Monitoring

Although manageable with certain precautions, circadian rhythm misalignment and sleep disturbances pose a potential threat to astronaut health. It is well-known that sleep is essential for proper immunological and neurological functioning, while impairments in these functions result in risks for spaceflight success. Neuropeptides and hormones are involved in regulating the circadian clock and are used as biomarkers for circadian alignment. However, in-flight monitoring of these biomarkers is limited due to the lack of real-time sensor systems and sample collection/processing confines. Therefore, real-time measurements of biomarkers in-flight are necessary for mission success and crew health. For this, a robust biomarker involved in the neuro-immune axis of circadian rhythm cycling, physiological stress responses, and inflammation would be well-received as a viable biomarker for assessing physiological health for crew during long-duration missions, as these are currently NASA Human Research Program defined risks. Therefore, this paper describes the development of a wearables we at biosensor to measure the biological clock neuropeptide, orexin/hypocretin. Additionally, potential for implementation of a user-friendly sensor of orexin/hypocretin to be telemetrically reported in real-time, is proposed. In brief, the proposed system has the possibility to be used as a biomarker monitor to support preventive and personalized medicine.

Amber M Paul↗
NASA NTRS1994

Continuous measurement of aircraft wing icing

Ice formation on the wings of aircraft is a problem that has plagued air travel since its inception. Several recent incidents have been attributed to ice formation on the lifting surfaces of wings. This paper describes a SBIR Phase 1 research effort on the use of small flat dielectric sensors in detecting a layer of ice above the sensor. The sensors are very small, lightweight, and inexpensive. The electronics package that controls the sensor is also small, and could be even smaller using commonly available miniaturization technologies. Thus, several sensors could be placed on a surface such that a representative ice thickness profile could be measured. The benefits offered by developing this technology go beyond the safety improvements realized by monitoring ice formation on the wings of an aircraft. Continuous monitoring of anti-icing fluid concentrations on the ground would warn the pilot of impending fluid failure as well as allowing the stations to use less de-icing solution per aircraft. This in turn would increase the safety of takeoffs and reduce the overall discharge of de-icing solution into the environment, thus reducing the biohazard of the de-icing procedure.

Yao, Stephen S. C.↗
NASA NTRS1977

A miniature 48-channel pressure sensor module capable of in situ calibration

A new high data rate pressure sensor module with in situ calibration capability has been developed by the Langley Research Center to help reduce energy consumption in wind-tunnel facilities without loss of measurement accuracy. The sensor module allows for nearly a two order of magnitude increase in data rates over conventional electromechanically scanned pressure sampling techniques. This module consists of 16 solid state pressure sensor chips and signal multiplexing electronics integrally mounted to a four position pressure selector switch. One of the four positions of the pressure selector switch allows the in situ calibration of the 16 pressure sensors; the three other positions allow 48 channels (three sets of 16) pressure inputs to be measured by sensors. The small size of the sensor module will allow mounting within many wind-tunnel models, thus eliminating long tube lengths and their corresponding slow pressure response.

Gross, C.↗
NASA NTRS1978

Electronically scanned pressure sensor module with in SITU calibration capability

This high data rate pressure sensor module helps reduce energy consumption in wind tunnel facilities without loss of measurement accuracy. The sensor module allows for nearly a two order of magnitude increase in data rates over conventional electromechanically scanned pressure sampling techniques. The module consists of 16 solid state pressure sensor chips and signal multiplexing electronics integrally mounted to a four position pressure selector switch. One of the four positions of the pressure selector switch allows the in situ calibration of the 16 pressure sensors; the three other positions allow 48 channels (three sets of 16) pressure inputs to be measured by the sensors. The small size of the sensor module will allow mounting within many wind tunnel models, thus eliminating long tube lengths and their corresponding slow pressure response.

Gross, C.↗
DOE OSTI2020

Market Survey of Airborne Small Unmanned Aircraft System Sensors February 2020

Sensors continue to decrease in size and power. This report presents results of a market survey conducted in February 2020 for commercial off-the-self sensors with optimal size, weight, and power to be carried onboard a small unmanned aircraft system. For this report, Sandia National Laboratories considered sensors that can detect an object in three dimensions. The sensors that were researched are broken into three categories: radio detection and ranging sensors, stereo camera sensors, and light detection and ranging sensors.

47 OTHER INSTRUMENTATION↗