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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 289 records · Page 16

Preliminary Results Using Galvanic Vestibular Reduction as a Non-Pharmaceutical Tool for Motion Sickness Mitigation

Alterations in vestibular sensory processing following G-transitions lead to motion sickness and spatial disorientation upon return to Earth’s gravity. The use of non-pharmaceutical mitigation for motion sickness has several potential advantages over drug treatment options. The purpose of this study was to validate a non-pharmaceutical tool using galvanic vestibular reduction (GVR) to mitigate G-transitional induced motion sickness and spatial disorientation.

G N Pradhan↗

Composing Teams with TEAMSTaR Tool for Evaluating and Mitigating Space Team Risk

As NASA sets its sights on more Earth-independent missions, the mission to Mars as a prime example, a team’s composition becomes a critical issue for mitigating the risks of such endeavors. The purpose of this project is to develop and validate TEAMSTaR (Tool for Evaluating And Mitigating Space Team Risks), a team composition decision support system that can be used by mission stakeholders (e.g., mission schedulers, crew members) to predict how a hypothetical team’s social relationships are likely to evolve and influence crew performance over the course of a mission. TEAMSTaR will enable decision makers to evaluate composition scenarios for a set of teams, for single-member replacements, and/or for subsets of teams.

N S Contractor↗

NASA Engineering and Safety Center Technical Bulletin No. 19-01-1: Mitigating Risks of Single-Event Effects in Space Applications

Since most Electrical, Electronic, and Electromechanical (EEE) parts are intended for terrestrial applications, they are susceptible to a range of radiation threats in the space environment if the resulting effects are not properly characterized and mitigated. Even specially designed radiation-hardened parts may not be tolerant to all types of radiation effects. Radiation hardness is a multi-dimensional property of any part that describes intrinsic abilities to tolerate various radiation environments [1,2]. Effects to be concerned with include total ionizing dose, total non-ionizing dose, and single-event effects (SEE) – all of which depend on the mission, environment, application, and lifetime. Radiation effects concerns may be the same whether a EEE part is Commercial-Off-The-Shelf (COTS), MIL-SPEC, or some other variant, all of which are susceptible to the same radiation threats [3]. SEE consequences range from recoverable faults to catastrophic failure. Like other random faults, SEE can be mitigated with informed circuit design practices at the device, card, and/or system level.

Single-event effects↗

Mitigation of Silver Ion Loss from Solution by Polymer Coating of Metal Surfaces, Part IV

“Spacecraft potable water systems require a biocidal agent that effectively provides both immediate and residual disinfection over long periods of time. Ionic silver (Ag+) is a leading candidate for this application, but suffers from rapid concentration loss due to interactions with the metallic storage containers and tubing. In order to maintain biocidal efficacy in systems with long periods of dormancy and to reduce the required rate of Ag+ injection, it is necessary to develop alternative materials and coatings for certified metal alloys that significantly reduce the Ag+ loss.” In previous reports, we have described our investigations addressing Ag+ loss mitigation and adhesion performance of parylene barrier coatings on coupons of several metal alloys and 316L tubing under static immersion. In such conditions, parylene-C and AF4 coatings have shown excellent Ag+ loss mitigation performance, and mixed long-term adhesion performance, depending on parylene species and substrate surface chemistry/structure. In Part IV of this series, we begin to address the performance of parylene-C barrier coatings under more challenging and realistic conditions, in order to evaluate potential suitability in flight systems. Using two testbeds, we characterized coating performance under dynamic mechanical operation. In the Flow/Pressure Testbed System, Ag+ solution is pumped through internally coated 316L tubing, with optional pressure cycling. In the Bellows Tank Testbed System, an internally coated edge-welded 316L bellows containing Ag+ solution is cyclically extended and compressed, analogous to the operation of bellows tanks used for potable water storage and delivery on the International Space Station. Periodic determinations of Ag+ loss with testbed cycling/time and visual observation of the parylene-C coatings were conducted. In addition, we characterized parylene-C coating resilience and Ag+ loss with 316L tubing and multiple fitting types under long-term immersion and repeated fitting dis/reassembly.

Lance Dean Delzeit↗

Logical shadow tomography: Efficient estimation of error-mitigated observables

We introduce a technique to estimate error-mitigated expectation values on noisy quantum computers. Our technique performs shadow tomography on a logical state to produce a memory-efficient classical reconstruction of the noisy density matrix. Using efficient classical post-processing, one can mitigate errors by projecting into the codespace as in subspace expansion and taking powers of the density matrix as in virtual distillation. Relative to subspace expansion which requires Ω (2^((n-1)k) samples to estimate a Pauli observable with an [[n; k]] stabilizer code, our technique requires only Ө(2^k) samples. Relative to virtual distillation, our technique can compute powers of the density matrix without implementing additional copies of quantum states the quantum computer. We present numerical results using logical states encoded with up to sixty physical qubits and show fast convergence to error-free expectation values with only 10^5 samples under 1% depolarizing noise.

quantum computing↗

Preliminary Results Using Galvanic Vestibular Reduction as a Non-Pharmaceutical Tool for Motion Sickness Mitigation

Introduction: Alterations in vestibular sensory processing following G-transitions lead to motion sickness and spatial disorientation upon return to Earth’s gravity. The use of non-pharmaceutical mitigation for motion sickness has several potential advantages over drug treatment options. The purpose of this study was to validate a non-pharmaceutical tool using galvanic vestibular reduction (GVR) to mitigate G-transitional induced motion sickness and spatial disorientation. Methods: Using a repeated measures counter-balanced design, motion sickness and perception are obtained during Coriolis cross-coupling stimuli on a rotating chair across three GVR treatment interventions: throughout stimulus testing (prevention), following symptom onset (rescue), and placebo control. Subjects perform up to 10 sets of pitch head movements during constant rotation. For each set, head movement is cued every 10 seconds, alternating between pitch forward (chin resting to chest) and pitch backward (head upright) for a total of 7 forward and backward movements. During each head movement, subjects are asked to use a joystick to record the magnitude of their perceived rotation along all three axes. During the 2-minute pause between sets, motion sickness symptom scoring was obtained using the Pensacola Diagnostic Index and subject discomfort (0-20) ratings. Performance on a sensorimotor and cognitive test battery is measured during a fourth session to map changes in GVR level with functional performance. Results: Fifteen of 30 subjects have completed testing to date. Preliminary findings suggest GVR may be more effective in reducing symptoms in subjects who self-report less susceptibility on a pre-test motion sickness susceptibility questionnaire. Based on the joystick measures, GVR significantly reduces both the magnitude (mean 22% - 34%) and duration (mean 42% - 49%) of perceived roll and pitch sensation with head movements during constant rotation. It is important to note that comparable levels of GVR (up to 2.5mA) does not impair performance on a functional test battery including mobility and balance tasks. Discussion: Our preliminary findings suggest GVR may be useful in reducing disorienting roll and pitch illusions associated with Coriolis cross-coupling stimuli. While transfer to post-flight treatment will need to be validated, the potential advantages of our non-pharmaceutical countermeasure approach would be to provide rapid therapeutic effect while allowing continuous titration of GVR amplitude during recovery to maintain operational performance.

Gaurav Pradhan↗

Logical Shadow Tomography: Efficient Estimation of Error-mitigated Observables

In near-term quantum applications, reducing errors and improving device reliability is an essential task. Towards these ends, various techniques have been introduced in recent literature, collectively referred to as quantum error mitigation techniques, for reducing errors in pre-fault-tolerant devices. Here, we introduce logical shadow tomography as a versatile error mitigation method. Our technique uses a stabilizer code to encode information in a logical state. Instead of doing active error correction, quantum states will be measured at the end of computation via shadow tomography and non-logical errors are projected out in the classical post-processing. Relative to quantum subspace expansion which requires O(2(M-1)L) experiments to estimate an logical Pauli observable encoded by an [[M, L, d]] code, our technique only requires 2L experiments, an important practical reduction in resources.

Hong-Ye Hu↗

Assessing Drought and Fire Conditions, Trends, and Susceptibility to Inform State Mitigation Efforts and Bolster Monitoring Protocol in North Central Idaho

Escalating severity and frequency of drought and wildfire call for effective and cost-efficient mitigation planning and monitoring protocols. The Palouse ecoregion, an agricultural epicenter in North-central Idaho, is of particular concern as both drought and wildfire present substantial economic threats. The DEVELOP team implemented Earth observation data to assist the Idaho Office of Emergency Management, Idaho Department of Water Resources, and Idaho Department of Lands in updating the state’s Hazard Mitigation Plan by enhancing their drought and fire monitoring capabilities. The team utilized Landsat 8 Operational Land Imager (OLI), and Aqua and Terra’s Moderate Resolution Imaging Spectroradiometer (MODIS), along with ancillary datasets, to assess drought indicators and map hazard susceptibility. The team upgraded the state’s current fire hazard model by updating existing data layers and adding drought indicator data to support partners’ continued assessment of fire hazard conditions. The team observed Evaporative Demand Drought Index (EDDI) spikes during the highest fire occurrence and burned area years in the study period: 2015 and 2021. Models from dry, high fire occurrence and burned area year 2015 outperformed models from mesic, low fire occurrence and burned area year 2016. The increased understanding of drought conditions and fire susceptibility in this ecosystem will assist partners in improving land management practices.

Ford Freyberg↗

Radiation Tolerance and Mitigation for Neuromorphic Processors

Neuromorphic processors are designed to execute Deep Neural Networks (DNNs) at very high speed using only a fraction of the electrical power needed to run a DNN on a traditional CPU or GPU. This unique capability makes Neuromorphic processors a prime candidate for space systems, where advanced computational tasks like image analysis, depth map reconstruction, or rover control need to be executed in a power-starved environment. In contrast to the growing number of applications of Neuromorphic processors in smart phones, the automotive and robotics domain, the space environment is unforgiving because of extreme temperatures and high levels of radiation. Any space system, operating beyond LEO requires computing hardware that is resilient against radiation effects. However, Neuromorphic processors have not yet been designed or tested for their radiation tolerance. In this report, we consider traditional methods of detection of radiation events and mitigation via redundancy and gauge their effectiveness on DNNs. In contrast to traditional flight software, however, neural networks represent a statistical algorithm, which might affect its resilience against radiation events. We will focus on the analysis of the tolerance of DNNs with respect to radiation events and discuss techniques to detect radiation hits using on-chip triple modular redundancy (TMR) on an Intel Loihi neuromorphic processor and to mitigate radiation damage. We describe an architecture for on-chip TMR for the Intel Loihi and present results of initial experiments.

Neural Networks↗

Lunar Dust Mitigation: A Guide and Reference: First Edition (2021)

On the surface of the Moon, lunar dust specifically presents unique challenges to operations long-term due to regolith particles’ ubiquitous presence in the lunar environment, potential to electrostatically charge and possible chemical reactivity. Whether to avoid exposure, try to remove or simply to tolerate lunar dust infiltrating a system becomes a complex question involving length of required service life, dust effects and critical risks, mass and complexity trades for the entire system. This publication provides a snapshot of advice from topical experts for specific areas of concern to systems targeted for deployment on the lunar surface. Following introductory overview commentary, dust mitigation approaches appropriate to the lunar surface are first addressed for typically static structures such as optical surfaces, radiators, and other thermal control surfaces, followed by regolith exposure concerns for communications equipment and non-optical sensors. The broad topic of mechanisms and mechanical assemblies is broken down to address relevant component level concerns, such as for bearings and for seals. “Soft goods” components of space suits (fabric) specific concerns are discussed, followed finally by brief coverage of human health issues and concerns, though the emphasis of this publication remains with components directly exposed to the harsh lunar surface environment. A description of some lunar surface hazard details, in particular characteristics of lunar surface dust, follows in Appendix A, and more detailed explanations of quantification issues for particulates are in Appendix B. The simple inertial removal of particles from a surface is discussed in Appendix C, followed by a summary of terrestrial best practices for dust mitigation recommended within select industries in Appendix D. The aggregated bibliography of references, while extensive and very useful, should not be construed to be exhaustive and can serve as a constructive start.

dust↗

Revisiting the Effectiveness of Debris Mitigation by Back-Dating Fragmentation Event

Since 1961, more than 250 satellites have fragmented while in orbit about the Earth, from very low Earth orbit out to the geostationary belt. The problem of orbital debris has been recognized since at least the late 1970s, with the institution of the NASA Orbital Debris Program Office (ODPO) in 1979 at the Johnson Space Center. Efforts to mitigate the growth of the orbital debris environment have mainly focused in two areas: the reduction and elimination of accidental explosions of spacecraft and rocket upper stages and the timely removal of spacecraft and rocket upper stages from orbit after completion of their missions. The ODPO continues to analyze the orbital population in orbit based on object type, mass, and other parameters of interest for characterizing the overall growth of objects in Earth’s orbit. Of the 268 known fragmentation events, 46 have occurred more than ten years after the affected satellites’ launch. These long-delayed breakups increase the population of orbital debris on the date of fragmentation, but we can also consider that the debris generated during that event could be attributed to the launch date of that satellite. We will present here an analysis of the historical growth of the low-Earth orbit debris environment, removing intentional fragmentation events, and examine the effectiveness of mitigation measures (such as passivation and reducing post-mission orbital lifetime).

Chris Ostrom↗

InVEST Urban Development: Incorporating Earth Observation Data into the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) Urban Flood Risk Mitigation Model Python API

Urban flooding poses as one of the biggest issues for cities today, as its impacts are amplified by both climate change and urbanization. The Natural Capital Project’s Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) Urban Flood Risk Mitigation (UFRM) model, which benefits from its simplicity and robustness, is commonly used in NASA DEVELOP projects for disaster mitigation, urban planning, and environmental justice issues. While InVEST UFRM model was able to produce the surface water runoff and retention map sufficient for the scopes of past projects, the model accuracy and spatial variability need improvement. Since the current InVEST UFRM model employs constant rainfall depth for all pixels in the area of interest (AOI), the model suffers from inaccurately estimating rainfall depth, runoff volume, and flood depth. Therefore, we adapted the model so that satellite-based precipitation raster datasets (i.e., Integrated Multi-satellitE Retrievals for Global Precipitation Measurement [GPM IMERG]) can be used instead of a single constant value. We simulated the flood events on August 21st and August 22nd, 2017 in Wyandotte County, Kansas using both our modified and the original InVEST UFRM model and then compared the results after incorporating the rainfall raster into the model. Areas with developed land on the land use map predicted moderate to high flood volume in the original volume regardless of the actual amount of precipitation. The modified model considered the rainfall depth’s spatial variation achieving less overestimation of flood runoff and volume at low-to-moderate rainfall area.

Son Do↗

Los Angeles Urban Development: Utilizing NASA Earth Observations to Evaluate the Impact of Tree Coverage on Urban Heat Mitigation

Over the last several decades the city of Los Angeles, California, has been experiencing increased temperatures resulting from the urban heat island effect. This is largely due to the expansion of developed areas which allow for the trapping of heat, posing dangerous health risks. As a solution, many organizations have turned to urban greening and tree planting initiatives to help cool vulnerable communities. NASA DEVELOP has partnered with City Plants and the City of Los Angeles, Office of Forest Management to study the role of trees in urban environments and their relation to the mitigation of local urban heat islands. This team used NASA Earth observation data spanning from 2016 to 2022, including land surface temperature and Normalized Difference Vegetation Index (NDVI) data collected from Landsat 8 Thermal Infrared Sensor (TIRS) and International Space Station (ISS) ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS), respectively. Data from the National Agriculture Imagery Program (NAIP) were also used to obtain a supervised classification of tree canopy cover. Our analysis reveals a spatial and temporal connection between temperature and vegetation, suggesting that areas with more vegetation are less likely to suffer high summertime temperatures. Results also highlight the impacts of tree planting programs, such as the Vermont Corridor planting project, which increased tree canopy cover by up to 5% in the community between 2016 and 2022. These findings support the implementation of urban greening practices and inform residents and officials about how investing in trees will help mitigate increasing heat within Los Angeles.

Urban heat island↗

InVEST Urban Development: Incorporating Earth Observation Data into the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) Urban Flood Risk Mitigation Model Python API

Urban flooding poses as one of the biggest issues for cities today as its impacts are amplified by both climate change and urbanization. The Natural Capital Project’s Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) Urban Flood Risk Mitigation (UFRM) model, which benefits from its simplicity and robustness, is commonly used in NASA DEVELOP projects for disaster mitigation, urban planning, and environmental justice issues. While the InVEST UFRM model was able to produce the surface water runoff and retention map sufficient for the scopes of past projects, the model’s accuracy and spatial variability need improvement. Since the current InVEST UFRM model employs constant rainfall depth for all pixels in the area of interest (AOI), the model suffers from inaccurately estimating rainfall depth, runoff volume, and flood depth. Therefore, we adapted the model so that satellite-based precipitation raster datasets (i.e., Integrated Multi-satellitE Retrievals for Global Precipitation Measurement [GPM IMERG]) can be used instead of a single constant value. We simulated the flood events on August 21st and August 22nd, 2017, in Wyandotte County, Kansas using both our modified and the original InVEST UFRM model and then compared the results after incorporating rainfall raster into the model. Areas with developed land on the land use map predicted moderate to high flood volume in the original volume regardless of the actual amount of precipitation. The modified model considered the rainfall depth’s spatial variation achieving less overestimation of flood runoff and volume at low-to-moderate rainfall area.

Urban flooding↗

Revisiting the Effectiveness of Debris Mitigation by Back-Dating Fragmentation Events

Since 1961, more than 250 satellites have fragmented while in orbit about the Earth, from very low Earth orbit out to the geostationary belt. The problem of orbital debris has been recognized since at least the late 1970s, with the institution of the NASA Orbital Debris Program Office (ODPO) in 1979 at the Johnson Space Center. Efforts to mitigate the growth of the orbital debris environment have mainly focused in two areas: the reduction and elimination of accidental explosions of spacecraft and rocket upper stages and the timely removal of spacecraft and rocket upper stages from orbit after completion of their missions. The ODPO continues to analyze the orbital population in orbit based on object type, mass, and other parameters of interest for characterizing the overall growth of objects in Earth’s orbit. Of the 268 known fragmentation events, 46 have occurred more than ten years after the affected satellites’ launch. These long-delayed breakups increase the population of orbital debris on the date of fragmentation, but we can also consider that the debris generated during that event could be attributed to the launch date of that satellite. We will present here an analysis of the historical growth of the low-Earth orbit debris environment, removing intentional fragmentation events, and examine the effectiveness of mitigation measures (such as passivation and reducing post-mission orbital lifetime).

Chris Ostrom↗

Sarasota Climate: Monitoring Heat and Assessing Heat Vulnerability to Identify Locations for Heat Mitigation Efforts in Sarasota, Florida

The coastal county of Sarasota, Florida, is located within the humid subtropical climate region and experiences an average of 250 days of sunshine every year. The county has large, urbanized communities which are vulnerable to urban heat island (UHI) effects. These rapidly growing communities contribute to the increasing surface temperatures and placing more residents at risk of heat-related illness. In partnership with Sarasota County Sustainability, the Sarasota Climate team utilized Earth observation data from NASA Landsat 8 and Landsat 9’s Thermal Infrared Sensors (TIRS), and the International Space Station’s Ecosystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) to model UHI effects within the county during the Summer for the last five years, 2019 to 2023. Data analysis with the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and Urban Heat Exposure Assessment Tempe 1.0 (UHEAT 1.0) models and within ModelBuilder produced maps that identified the land surface temperature (LST) variance within the county, the regions that are most susceptible to extreme heat, and areas least capable of mitigating the effects of UHI. The results revealed that heat intensity varies significantly across Sarasota County with the highest temperatures in the more developed western part of the county. Additionally, the team identified that there are at least three vulnerable communities that exist in high-heat regions, including North Sarasota, Venice, and North Port. These regions have an overlap between socioeconomic sensitivity and environmental hazard that indicate a high priority in future heat mitigation efforts.

Remote sensing↗

Transfer of NASA Technology to the DoD: Mitigating Motion Sickness with Autogenic Feedback Training Exercise

Motion sickness poses a significant safety risk, particularly in the context of aviation. Given its prevalence among aviators and its detrimental impact on performance, researchers have attempted to identify effective mitigation strategies for motion sickness. Currently, many of the existing interventions are pharmacological, and while effective, they present a problem due to their associated adverse side effects. The primary goals of the current research were 1) demonstrate the value of the application of Autogenic-Feedback Training Exercise (AFTE), a physiological training program developed by NASA to mitigate the impact of operational stressors such as motion sickness and spatial disorientation on human physiology and performance and 2) evaluate a new enhanced version of AFTE training software and demonstrate the ability to apply it remotely and train other personnel to administer it. AFTE combines principles of autogenic therapy, and biofeedback in training individuals to control their physiological reactions through a series of relaxation and arousal exercises. This study included twenty-six participants, 17 men and 9 women. On day 1 participants were tested in a rotating chair (pre-test) to determine their motion sickness tolerance (measured as minutes of rotation); days 2-5 consisted of four AFTE training sessions, each 30-min. in duration for a total of 2 hours; and on day 6 the participants were re-tested in the rotating chair. Results revealed a significant increase in motion sickness tolerance with AFTE on the post-test when compared to pre-test, participants had significantly lower symptom diagnostic scores post-test, and there was no significant gender effect. In addressing the first goal it was concluded that the modified 2-hour version of AFTE significantly improved motion sickness tolerance with participants experiencing fewer symptoms. A second goal of this research was to refine and transfer a NASA technology, software and methods for applications within DOD by training other personnel to administer AFTE. A comparison of NASA and NAMRU-D trainers on AFTE outcome for improving participants’ motion sickness tolerance revealed no significant difference indicating the successful transfer of methods to DOD. In addition, remote AFTE training of military aviators at distant sites was feasible. A third goal was to identify individual patterns of interoceptive abilities and related autonomic metrics able to predict stress response and training outcome. These data included measures of personality traits obtained from questionnaires and specific autonomic measures (e.g., heart rate variability) collected by NAMRU-D investigators. These results will be reported in a separate paper.

autonomic nervous system↗

Mitigation of High Lateral Asymmetry Rates Due to Loss of a Cruise Motor on the X-57 Mod III Aircraft

The X-57 Mod III aircraft utilizes wingtip electric motors to generate thrust. The potential benefit of wingtip propulsion is a reduction in induced drag because wingtip vortices are interrupted. Wingtip propulsors, however, pose the risk of dangerous thrust asymmetry if one of the motors abruptly stops producing full thrust. This paper examines the effects of a full-power, single-motor failure at various phases of flight for the X-57 Mod III aircraft design by way of piloted-in-the-loop simulations conducted by two National Aeronautics and Space Administration test pilots. After determining that a failure during takeoff potentially poses the highest risk of catastrophic consequences, possible mitigations to the failure were explored and evaluated through pilot simulation data, Cooper-Harper ratings, and pilot comments. The preferred mitigation was found to be an automated power reduction system that allowed for a lower pilot workload and quick reduction of the asymmetric thrust.

Ryan Wallace↗