Search NASA⌕ Search

SEARCH · Search NASA

Results for “Portable Performance”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 703 records · Page 39
All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

Testing and Results of Vacuum Swing Adsorption Units for Spacesuit Carbon Dioxide and Humidity Control

A principal concern for extravehicular activity (EVA) space suits is the capability to control carbon dioxide (CO2) and humidity (H2O) for the crewmember. The release of CO2 in a confined or unventilated area is dangerous for human health and leads to asphyxiation; therefore, CO2 and H2O become leading factors in the design and development of the spacesuit. An amine-based CO2 and H2O vapor sorbent for use in pressure-swing re-generable beds has been developed by Hamilton Sundstrand. The application of solid-amine materials with vacuum swing adsorption technology has shown the capacity to concurrently manage CO2 and H2O levels through a fully regenerative cycle eliminating mission constraints imposed with non-regenerative technologies. Two prototype solid amine-based systems, known as rapid cycle amine (RCA), were designed to continuously remove CO2 and H2O vapor from a flowing ventilation stream through the use of a two-bed amine based, vacuum-swing adsorption system. The Engineering and Science Contract Group (ESCG) RCA is the first RCA unit implementing radial flow paths, whereas the Hamilton Sundstrand RCA was designed with linear flow paths. Testing was performed in a sea-level pressure environment and a reduced-pressure environment with simulated human metabolic loads in a closed-loop configuration. This paper presents the experimental results of laboratory testing for a full-size and a sub-scale test article. The testing described here characterized and evaluated the performance of each RCA unit at the required Portable Life Support Subsystem (PLSS) operating conditions. The test points simulated a range of crewmember metabolic rates. The experimental results demonstrate the ability of each RCA unit to sufficiently remove CO2 and H2O from a closed loop ambient or subambient atmosphere.

McMillin, Summer↗
NASA NTRS2011

Testing and Results of Vacuum Swing Adsorption Units for Spacesuit Carbon Dioxide and Humidity Control

A principal concern for extravehicular activity (EVA) spacesuits is the capability to control carbon dioxide (CO2) and humidity (H2O) for the crewmember. The release of CO2 in a confined or unventilated area is dangerous for human health and leads to asphyxiation; therefore, CO2 and H2O control become leading factors in the design and development of the spacesuit. An amine-based CO2 and H2O vapor sorbent for use in pressure-swing regenerable beds has been developed by Hamilton Sundstrand. The application of solidamine materials with vacuum swing adsorption technology has shown the capacity to concurrently manage CO2 and H2O levels through a fully regenerative cycle eliminating mission constraints imposed with nonregenerative technologies. Two prototype solid amine-based systems, known as rapid cycle amine (RCA), were designed to continuously remove CO2 and H2O vapor from a flowing ventilation stream through the use of a two-bed amine based, vacuum-swing adsorption system. The Engineering and Science Contract Group (ESCG) RCA implements radial flow paths, whereas the Hamilton Sundstrand RCA was designed with linear flow paths. Testing was performed in a sea-level pressure environment and a reduced-pressure environment with simulated human metabolic loads in a closed-loop configuration. This paper presents the experimental results of laboratory testing for a full-size and a sub-scale test article. The testing described here characterized and evaluated the performance of each RCA unit at the required Portable Life Support Subsystem (PLSS) operating conditions. The test points simulated a range of crewmember metabolic rates. The experimental results demonstrated the ability of each RCA unit to sufficiently remove CO2 and H2O from a closed loop ambient or sub-ambient atmosphere.

McMillin, Summer D.↗
NASA NTRS2012

Evolved Gas Analysis of Mars Analog Samples from the Arctic Mars Analog Svalbard Expedition: Implications for Analyses by the Mars Science Laboratory

The 2011 Arctic Mars Analog Svalbard Expedition (AMASE) investigated several geologic settings on Svalbard, using methodologies and techniques being developed or considered for future Mars missions, such as the Mars Science Laboratory (MSL). The Sample Analysis at Mars (SAM) instrument suite on MSL consists of a quadrupole mass spectrometer (QMS), a gas chromatograph (GC), and a tunable laser spectrometer (TLS), which analyze gases created by pyrolysis of samples. During AMASE, a Hiden Evolved Gas Analysis-Mass Spectrometer (EGA-MS) system represented the EGA-QMS capability of SAM. Another MSL instrument, CheMin, will use x-ray diffraction (XRD) and x-ray fluorescence (XRF) to perform quantitative mineralogical characterization of samples. Field-portable versions of CheMin were used during AMASE. AMASE 2011 sites spanned a range of environments relevant to understanding martian surface materials, processes and habitability. They included the basaltic Sverrefjell volcano, which hosts carbonate globules, cements and coatings, carbonate and sulfate units at Colletth0gda, Devonian sandstone redbeds in Bockfjorden, altered basaltic lava delta deposits at Mt. Scott Keltie, and altered dolerites and volcanics at Botniahalvoya. Here we focus on SAM-like EGA-MS of a subset of the samples, with mineralogy comparisons to CheMin team results. The results allow insight into sample organic content as well as some constraints on sample mineralogy.

McAdam, A.↗
NASA NTRS2024

Safe Exploration: Sensorimotor Assessments for Early Extravehicular Activities

BACKGROUND: Artemis missions will require a new level of crew autonomy around periods of gravitational transition, where sensorimotor disturbances are at their highest. There is a need to define performance thresholds for key sensorimotor assessments that indicate when performance in early extravehicular activities (EVAs) might be impacted or unsafe. This panel presentation will discuss the development of sensorimotor assessments for determining crew preparedness of early EVAs by utilizing a novel portable sensorimotor disorientation analog and other spaceflight analogs. OVERVIEW: To define performance thresholds, a proposed set of sensorimotor assessment tasks must be validated under various spaceflight analogs. A Sensorimotor Disorientation Analog (SDA) was developed that could induce varying levels of disorientation through combined vestibular (galvanic vestibular stimulation (GVS)) and proprioceptive (weighted chest, ankles, and wrists) disruptions. The SDA was first pilot tested using subjective feedback from previously flown astronauts to determine the levels of disorientation that mimic motor performance immediately (R+0) and +24 hours (R+1) postflight. A second study was performed using healthy non-astronaut ground subjects to validate the SDA levels by comparing to astronaut postflight data. The validated SDA was utilized in a third study to map performance in the proposed set of sensorimotor assessment tasks to operational tasks. The assessment tasks were defined based on lessons learned from Apollo and subject matter experts (e.g., flight surgeons) to include the following: 1) aid in progressive adaptation to the novel gravitational environment; 2) provide opportunities to develop strategies to recover from off-nominal body positions; and 3) mimic operational tasks such that crew can self-assess their potential ability to complete their missions. This presentation will conclude with a discussion on future validation studies of the proposed assessment tasks using other spaceflight analogs such as centrifugation and gravity offload systems. DISCUSSION: Exploration class missions will require crew to be able to self-assess and treat their sensorimotor dysfunction after gravity transitions, and in off-nominal situations they may be required to perform provocative, challenging tasks soon after landing. This panel presentation will discuss current and ongoing research strategies to address the sensorimotor risk on safe exploration during Artemis missions.

Sarah Moudy↗
DOE OSTI2018

A 3D-Printed Microresonator Based on the Quartz-Enhanced Photoacoustic Spectroscopy Sensor for Methane Detection

A 3D-printed microresonator based on a quartz tuning fork has been developed. The sensor performance is evaluated by detection of methane with a fiber-coupled distributed feedback diode laser. In combination with wavelength modulation spectroscopy, a minimum detectable concentration of 15.6 ppb by volume is achieved at atmospheric pressure with an 8-mW average optical excitation power and a lock-in amplifier time constant of 1 s, which corresponds to a 1σ normalized noise equivalent absorption coefficient of 5·10{sup –9} cm{sup –1}·W/Hz{sup 1/2}. An Allan variance analysis shows that the system has long-term stability and can serve as the basis for a portable gas analyzer. Approaches to improve the current sensor performance are also discussed. This design greatly reduces the time of manufacturing the microresonator.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS2023

Ventilation Heat Exchanger / Flow Meter for xPLSS

The flow meter / heat exchanger (FMHX) in the ventilation loop of the exploration EMU cools the ventilation gas and measures the ventilation flow rate. The heat exchanger transfers heat from the ventilation gas to the thermal control loop via a miniature shell-and-tube heat exchanger. The flow meters calculate the flow rate of gas through the ventilation loop based on the pressure drop across the heat exchanger core. Creare has delivered four design validation test (DVT) heat exchangers and five DVT flow meters to NASA JSC to support development of the exploration portable life support system (xPLSS). This paper describes the design and performance of the DVT units.The heat exchangers are designed to cool the ventilation gas to a specified temperature with low pressure losses under the most challenging operating conditions. The measured performance of the DVT heat exchangers agrees well with design models and meets all performance requirements. The flow meters use a MEMS thermal flow sensor to produce a signal that is proportional to a small bypass flow around the heat exchanger core. They are designed to achieve high measurement accuracy across the full range of xPLSS operating conditions. We calibrated the flow meters in a special-purpose flow facility that simulates operation in the xPLSS ventilation loop. Calibration testing shows that DVT flow meters produce digital output for vent loop mass flow that meets NASA’s accuracy requirements across the range of xPLSS operating conditions. This paper reviews the design of the heat exchangers and flow meters and presents data from the final flow meter calibration testing, heat exchanger performance validation, and initial ground testing in NASA’s xPLSS.

spacesuit↗
NASA NTRS2023

Ventilation Heat Exchanger / Flow Meter for xPLSS

The flow meter / heat exchanger (FMHX) in the ventilation loop of the exploration EMU cools the ventilation gas and measures the ventilation flow rate. The heat exchanger transfers heat from the ventilation gas to the thermal control loop via a miniature shell-and-tube heat exchanger. The flow meters calculate the flow rate of gas through the ventilation loop based on the pressure drop across the heat exchanger core. Creare has delivered four design validation test (DVT) heat exchangers and five DVT flow meters to NASA JSC to support development of the exploration portable life support system (xPLSS). This paper describes the design and performance of the DVT units.The heat exchangers are designed to cool the ventilation gas to a specified temperature with low pressure losses under the most challenging operating conditions. The measured performance of the DVT heat exchangers agrees well with design models and meets all performance requirements. The flow meters use a MEMS thermal flow sensor to produce a signal that is proportional to a small bypass flow around the heat exchanger core. They are designed to achieve high measurement accuracy across the full range of xPLSS operating conditions. We calibrated the flow meters in a special-purpose flow facility that simulates operation in the xPLSS ventilation loop. Calibration testing shows that DVT flow meters produce digital output for vent loop mass flow that meets NASA’s accuracy requirements across the range of xPLSS operating conditions. This paper reviews the design of the heat exchangers and flow meters and presents data from the final flow meter calibration testing, heat exchanger performance validation, and initial ground testing in NASA’s xPLSS.

spacesuit↗
DOE OSTI2025

Flexible transparent conducting electrodes unexpectedly influence MAPbI 3 film morphology and perovskite solar cell performance

Fabricating perovskite solar cells (PSCs) on plastic substrates will enable cost-effective manufacturing of lightweight and portable energy systems. Here, we study the influence of flexible transparent conductive electrodes (TCEs) on the methylammonium lead iodide (MAPbI3) film morphology and PSC performance. Three types of TCEs on polyethylene terephthalate (PET) are compared: a custom-made AgNWs/indium zinc oxide hybrid TCE and two commercial substrates with indium tin oxide (ITO) or metal/insulator/metal (MIM) as the TCE. Using the same p-i-n architecture and hole transport layer (HTL), we find that PSCs fabricated on the hybrid TCE show better performance and stability compared to those made on commercial TCEs. The PSC performance enhancement is attributed to the superior structural and optical properties of MAPbI3 film deposited on the hybrid TCE, which is explained by the surface energy difference of the HTL. While it is anticipated that solar cell performance can be affected by TCEs’ transmittance and sheet resistance as they determine light absorption and carrier transport, respectively, our finding of TCE influencing the morphology and crystallinity of MAPbI3 film, and hence PSC performance, is unexpected.

14 SOLAR ENERGY↗
DOE OSTI2022

LaRIS: Targeting Portability and Productivity for LAPACK Codes on Extreme Heterogeneous Systems by Using IRIS

In keeping with the trend of heterogeneity in high-performance computing, hardware manufacturers and vendors are developing new architectures and associated software stacks (e.g., libraries) to harness the best possible performance from commonly used kernels (e.g., linear algebra kernels). However, kernels tuned for one architecture are not portable to others. Moreover, the coexistence of different architectures in a single node makes orchestration difficult. To address these challenges, we introduce LaRIS, a portable framework for LAPACK functionalities. LaRIS ensures a separation between linear algebra algorithms and vendor-library kernels by using the IRIS run time and IRIS-BLAS library. Such abstraction at the algorithm level makes the implementation completely agnostic to the vendor library and architecture. LaRIS uses the IRIS run time to dynamically select the vendor-library kernel and suitable processor architecture at run time. Through LU factorization, we demonstrate that LaRIS can fully utilize different heterogeneous systems by launching and orchestrating different vendor-library kernels without any change in the source code.

Monil, M. A. H.↗
NASA NTRS2014

Use of a New Portable Instrumented Impactor on the NASA Composite Crew Module Damage Tolerance Program

Damage tolerance performance is critical to composite structures because surface impacts at relatively low energies may result in a significant strength loss. For certification, damage tolerance criteria require aerospace vehicles to meet design loads while containing damage at critical locations. Data from standard small coupon testing are difficult to apply to larger more complex structures. Due to the complexity of predicting both the impact damage and the residual properties, damage tolerance is demonstrated primarily by testing. A portable, spring-propelled, impact device was developed which allows the impact damage response to be investigated on large specimens, full-scale components, or entire vehicles. During impact, both the force history and projectile velocity are captured. The device was successfully used to demonstrate the damage tolerance performance of the NASA Composite Crew Module. The impactor was used to impact 18 different design features at impact energies up to 35 J. Detailed examples of these results are presented, showing impact force histories, damage inspection results, and response to loading.

Jackson, Wade C.↗
DOE OSTI2022

3D LiMn 2 O 4 nThin Film Deposited by ALD: A Road toward High-Capacity Electrode for 3D Li-Ion Microbatteries

Miniaturized electronics suffer from a lack of energy autonomy. In that context, the fabrication of lithium-ion solid-state microbatteries with high performance is mandatory for powering the next generation of portable electronic devices. Here, the fabrication of a thin film positive electrode for 3D Li-ion microbatteries made by the atomic layer deposition (ALD) method and in situ lithiation step is demonstrated. The 3D electrodes based on spinel LiMn 2 O 4 films operate at high working potential (4.1 V vs Li/Li + ) and are capable of delivering a remarkable surface capacity (approximate to 180 mu Ah cm -2 ) at low C-rate while maintaining more than 40 mu Ah cm -2 at C/2 (time constant = 2 h). Both the thickness of the electrode material and the 3D gain of the template are carefully tuned to maximize the electrode performance. Further, advanced characterization techniques such as transmission electron and X-ray transmission microscopies are proposed as perfect tools to study the conformality of the deposited films and the interfaces between each layer: no interdiffusion or segregation are observed. This work represents a major issue towards the fabrication of 3D-lithiated electrode by ALD-without any prelithiation step by electrochemical technique-making it an attractive solution for the fabrication of 3D Li-ion solid-state microbatteries with semiconductor processing methods.

3D Li-ion micro-batteries↗
DOE OSTI2018

Hybrid Graphene Ribbon/Carbon Electrodes for High‐Performance Energy Storage

Abstract The utility of supercapacitors for both fixed and portable energy storage would be greatly enhanced if their energy density could be increased while maintaining their high power density, fast charging time, and low cost. This study describes a simple, solution‐phase, scalable modification of carbon materials by a covalently bonded “brush” of hydrogen‐terminated graphene ribbons (GRs) with layer thicknesses of 2–20 nm, resulting in a 20–100 times increase in the areal capacitance of the unmodified electrode surface. On a flat sp 2 carbon surface modified by GRs, the capacitance exceeds 1200 µF cm −2 in 0.1 m H 2 SO 4 due to a distinct type of pseudocapacitance during constant current charge/discharge cycling. Modification of high surface area carbon black electrodes with GRs yields capacitances of 950–1890 F g −1 , power densities >40 W g −1 , and minimal change in capacitance during 1500 charge/discharge cycles at 20 A g −1 . A capacitance of 1890 F g −1 affords an energy density of 318 Wh kg −1 operating at 1.1 V and 590 Wh kg −1 at 1.5 V. The projected energy density of a hybrid GR/carbon supercapacitor greatly exceeds the current 10 Wh kg −1 for commercial supercapacitors and approaches that of lithium ion batteries.

Farquhar, Anna K.↗
DOE OSTI2025

Portable Tank Storage Pit Technical Documents and Associated Flooring Documents

The work performed under this section includes the surface preparation and application of protective floor coatings; furnishing all labor, materials, and equipment necessary to perform all operations in connection with the application required for satisfactory completion in accordance with the standards and practices set forth herein.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2019

IMPROVING INTERMEDIATE TEMPERATURE PERFORMANCE OF NI-YSZ CERMET ANODES FOR SOLID OXIDE FUEL CELLS BY INFILTRATION OF NICKEL NANOPARTICLES AND MIXED IONIC ELECTRONIC CONDUCTOR

Solid oxide fuel cells (SOFCs) are one of the most efficient and environment-friendly devices for electricity generation. One critical challenge of SOFC commercialization is high cell operating temperatures (800°C-1000°C), which lead to high material costs, high performance degradation rates, long start-up and shutdown times, and limited portable applications. Intermediate temperature (600°C-800°C) operation of SOFCs is limited by sluggish electrode reaction kinetics. The objective of this research is to improve intermediate temperature performance of commercially available Ni-YSZ cermet anode supported SOFCs by liquid infiltration of the anode. One effective method to improve kinetics of electrochemical reactions at the anode is to increase the density of reaction sites, which are known as the triple phase boundaries (TPBs). The porous Ni-YSZ cermet anodes were liquid infiltrated with Ni nanoparticles, leading to a four-fold increase in TPB density in the anode. The improved electrochemical performance of the infiltrated cells compared to the uninfiltrated cells highlights the effectiveness of anode infiltration in facilitating improved anode electrochemical reaction kinetics. However, the post-electrochemical testing characterization revealed that Ni nanoparticles were not stable due to Ni coarsening and were mostly isolated indicating that not all of the additional TPBs were fully utilized in electrochemical reactions due to the lack of an electronic pathway between the Ni nanoparticles. In order to improve microstructural stability of the infiltrated Ni nanoparticles, and to fully utilize the added TPBs, co-infiltration of Ni with a mixed ionic and electronic conductor (MIEC) was carried out. Two MIEC materials are chosen based on their chemical stability and conductivity in the anode operating environments; Gd 0.1 Ce 0.9 O 2-δ (GDC), a predominantly an ionic conductor, and La 0.6 Sr 0.3 Ni 0.15 Cr 0.85 O 3-δ (LSNC), a predominantly electronic conductor, and cells were successfully co-infiltrated to form Ni-GDC and Ni-LSNC nanostructures with the MIEC phases connecting the Ni nanoparticles. Stability tests demonstrated that both MIECs inhibited Ni nanoparticle coarsening. Electrochemical studies showed that Ni-GDC is the most effective for improved anode kinetics. A long-term (120 hours) electrochemical test indicated that infiltration of Ni-GDC into Ni-YSZ cermet anode effectively improves overall cell performance at intermediate temperatures and maintains the performance gain for a long period of time.

Lu, Yanchen↗
DOE OSTI2022

Portable aircraft controller devices and systems

A portable computerized device for an aircraft control system includes an input system for inputting commands, a device display for displaying information on the computerized device, a processor, a wireless communication module, and a non-transitory computer readable medium comprising computer executable instructions, the computer executable instructions configured to cause the processor to perform a method. The method can include detecting whether the portable computerized device is in a cockpit state such that the portable computerized device is in and/or docked to an aircraft cockpit or if the portable computerized device is in a remote state such that the portable computerized device is not in an aircraft cockpit or is not docked to an aircraft cockpit. If the portable computerized device is determined to be in a remote state, the method includes operating the remote device in a remote mode. If the portable computerized device is determined to be in a cockpit state, the method includes operating the device in a local mode.

Sahay, Prateek↗
NASA NTRS1998

The Design and Evaluation of "CAPTools"--A Computer Aided Parallelization Toolkit

Writing applications for high performance computers is a challenging task. Although writing code by hand still offers the best performance, it is extremely costly and often not very portable. The Computer Aided Parallelization Tools (CAPTools) are a toolkit designed to help automate the mapping of sequential FORTRAN scientific applications onto multiprocessors. CAPTools consists of the following major components: an inter-procedural dependence analysis module that incorporates user knowledge; a 'self-propagating' data partitioning module driven via user guidance; an execution control mask generation and optimization module for the user to fine tune parallel processing of individual partitions; a program transformation/restructuring facility for source code clean up and optimization; a set of browsers through which the user interacts with CAPTools at each stage of the parallelization process; and a code generator supporting multiple programming paradigms on various multiprocessors. Besides describing the rationale behind the architecture of CAPTools, the parallelization process is illustrated via case studies involving structured and unstructured meshes. The programming process and the performance of the generated parallel programs are compared against other programming alternatives based on the NAS Parallel Benchmarks, ARC3D and other scientific applications. Based on these results, a discussion on the feasibility of constructing architectural independent parallel applications is presented.

Yan, Jerry↗
NASA NTRSDate not supplied

A Portable High-Density Power Technology for Space, Lunar, and Planetary Applications

A new direct energy conversion concept called Nuclear Thermionic Avalanche Cell (NTAC) combined with a Metallic Junction Thermoelectric (MJ-TE) generator, both invented and patented by NASA, offers high specific power for portable applications. Estimates based on experimental results suggest superior performance compared to radioisotope thermoelectric generators (RTG) by up to two orders of magnitude for the NTAC and three to four times better for the MJ-TE generator for the same mass. The NTAC technology can use a variety of radioisotopes including nuclear waste to liberate a large number of intra-band(IB), inner shell electrons of atoms (105 C/cm3) by gamma-ray photons (100 keV to MeV). In contrast, conventional power generation has poor specific power because they only utilize the valence band electrons (3C/cm3) of the semiconductor or free electrons (8×103 C/cm3) of the conductor.

NTAC↗
NASA NTRS2016

On the Efficacy of Isolating Shoulder and Elbow Movements with a Soft, Portable, and Wearable Robotic Device

Treatment intensity has a profound effect on motor recovery following neurological injury. The use of robotics has potential to automate these labor-intensive therapy procedures that are typically performed by physical therapists. Further, the use of wearable robotics offers an aspect of portability that may allow for rehabilitation outside the clinic. The authors have developed a soft, portable, lightweight upper extremity wearable robotic device to provide motor rehabilitation of patients with affected upper limbs due to traumatic brain injury (TBI). A key feature of the device demonstrated in this paper is the isolation of shoulder and elbow movements necessary for effective rehabilitation interventions. Herein is presented a feasibility study with one subject and demonstration of the device's ability to provide safe, comfortable, and controlled upper extremity movements. Moreover, it is shown that by decoupling shoulder and elbow motions, desired isolated joint actuation can be achieved.

Kadivar, Zahra↗