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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 1,081 records · Page 60
All sourcesNASA NTRSDOE OSTI
NASA NTRS1999

Circadian regulation of human sleep and age-related changes in its timing, consolidation and EEG characteristics

The light-entrainable circadian pacemaker located in the suprachiasmatic nucleus of the hypothalamus regulates the timing and consolidation of sleep by generating a paradoxical rhythm of sleep propensity; the circadian drive for wakefulness peaks at the end of the day spent awake, ie close to the onset of melatonin secretion at 21.00-22.00 h and the circadian drive for sleep crests shortly before habitual waking-up time. With advancing age, ie after early adulthood, sleep consolidation declines, and time of awakening and the rhythms of body temperature, plasma melatonin and cortisol shift to an earlier clock hour. The variability of the phase relationship between the sleep-wake cycle and circadian rhythms increases, and in old age sleep is more susceptible to internal arousing stimuli associated with circadian misalignment. The propensity to awaken from sleep advances relative to the body temperature nadir in older people, a change that is opposite to the phase delay of awakening relative to internal circadian rhythms associated with morningness in young people. Age-related changes do not appear to be associated with a shortening of the circadian period or a reduction of the circadian drive for wake maintenance. These changes may be related to changes in the sleep process itself, such as reductions in slow-wave sleep and sleep spindles as well as a reduced strength of the circadian signal promoting sleep in the early morning hours. Putative mediators and modulators of circadian sleep regulation are discussed.

Review, Tutorial↗
NASA NTRS2005

Development of a Coherent Lidar for Aiding Precision Soft Landing on Planetary Bodies

Coherent lidar can play a critical role in future planetary exploration missions by providing key guidance, navigation, and control (GNC) data necessary for navigating planetary landers to the pre-selected site and achieving autonomous safe soft-landing. Although the landing accuracy has steadily improved over time to approximately 35 km for the recent Mars Exploration Rovers due to better approach navigation, a drastically different guidance, navigation and control concept is required to meet future mission requirements. For example, future rovers will require better than 6 km landing accuracy for Mars and better than 1 km for the Moon plus maneuvering capability to avoid hazardous terrain features. For this purpose, an all-fiber coherent lidar is being developed to address the call for advancement of entry, descent, and landing technologies. This lidar will be capable of providing precision range to the ground and approach velocity data, and in the case of landing on Mars, it will also measure the atmospheric wind and density. The lidar obtains high resolution range information from a frequency modulated-continuous wave (FM-CW) laser beam whose instantaneous frequency varies linearly with time, and the ground vector velocity is directly extracted from the Doppler frequency shift. Utilizing the high concentration of aerosols in the Mars atmosphere (approx. two order of magnitude higher than the Earth), the lidar can measure wind velocity with a few watts of optical power. Operating in 1.57 micron wavelength regime, the lidar can use the differential absorption (DIAL) technique to measure the average CO2 concentration along the laser beam using, that is directly proportional to the Martian atmospheric density. Employing fiber optics components allows for the lidar multi-functional operation while facilitating a highly efficient, compact and reliable design suitable for integration into a spacecraft with limited mass, size, and power resources.

Amzajerdian, Farzin↗
NASA NTRS1996

Risk as a Resource: A New Paradigm

In the new NASA, risk management must be developed as a skill to a far greater degree than has existed in the past. Past approaches have produced great successes but at great cost and lengthy schedules. In the future, risk and its component contributors must be re-evaluated. There are three contexts of risk that will be addressed in this paper: risk as a resource, which expands and shifts traditional risk considerations; marginal cost of risk, which addresses the cumulative and time related effects of risk reduction; and an alternative definition or new meaning of success and how it relates to work.

risk management risk success mission risk↗
NASA NTRS1996

Accuracy of the Residual Delay Absolute Phase Algorithm

Interferometric synthetic aperture radar (IFSAR) has become a useful technology for producing high-quality topographic maps. These measurements are required to reconstruct the three-dimensional coordinate of a point in an IFSAR image: the range, azimuth and elevation. The first is obtained by timing the return of the radar pulse, the second by measuring the doppler shift, and the last by measuring the phase difference between the signals received at two displaced antennae.

IFSAR interferometric synthetic aperture radar top↗
NASA NTRS1989

Method and apparatus for measuring frequency and phase difference

A system for deriving direct digital indications of frequency and phase difference between two incoming pulse trains adaptable for collision avoidance systems or the like. A pair of radar beams 152 and 152A are directed toward a target 153 and corresponding beams 154 and 154A returning therefrom are detected. A digital difference circuit 110 forms a pulse train 66 from the Doppler shift frequencies of each beam pair having a repetition rate functionally related to the difference in magnitude of the shift frequencies. Pulses from the pulse train are counted as a function of time. Visual indications thereof on display 144 are correlative to target position relative to beams 152 and 152A.

Kobayashi, Herbert S.↗
NASA NTRS2017

Correlation Between Soil Moisture and Dust Emissions: An Investigation for Global Climate Modeling

This work is using the newly available NASA SMAP soil moisture measurement data to evaluate its impact on the atmospheric dust emissions. Dust is an important component of atmospheric aerosols, which affects both climate and air quality. In this work, we focused on semi-desert regions, where dust emissions show seasonal variations due to soil moisture changes, i.e. in Sahel of Africa. We first identified three Aerosol Robotic Network (AERONET) sites in the Sahel (IER_Cinzana, Banizoumbou, and Zinder_Airport). We then utilized measurements of aerosol optical depth (AOD), fine mode fraction, size distribution, and single-scattering albedo and its wave-length dependence to select dust plumes from the available measurements We matched the latitude and longitude of the AERONET station to the corresponding SMAP data cell in the years 2015 and 2016, and calculated their correlation coefficient. Additionally, we looked at the correlation coefficient with a three-day and a five-day shift to check the impact of soil moisture on dust plumes with some time delay. Due to the arid nature of Banizoumbou and Zinder_Airport, no correlation was found to exist between local soil moisture and dust aerosol load. While IER_Cinzana had soil moisture levels above the satellite threshold of 0.02cm3/cm3, R-value approaching zero indicated no presence of a correlation. On the other hand, Ilorin demonstrated a significant negative correlation between aerosol optical depth and soil moisture. When isolating the analysis to Ilorin's dry season, a negative correlation of -0.593 was the largest dust-isolated R-value recorded, suggesting that soil moisture is driven the dust emission in this semi-desert region during transitional season.

climate↗
NASA NTRS2018

Autonomous Power Control

Intelligent autonomous control of a spacecraft is an enabling technology that must be developed for deep space human exploration. NASA's current long term human space platform, the International Space Station which is in Low Earth Orbit, is in almost continuous communication with ground based mission control. This allows near realtime operation of all the vehicle core systems, including power, from the ground. As the focus shifts from Low Earth Orbit to deep space, challenges associated with communication time-lag and bandwidth limitations beyond geosynchronous orbit do not permit this type of ground based operation. These communication limitations motivate autonomous vehicle operations, including the vehicle subsystems such as power. This presentation will describe the ongoing development of an Autonomous Power Control (APC) system that can be used for a deep space exploration spacecraft. This work extends previous work on developing an autonomous power control which includes developing a control architecture for deep space vehicles, the use of software agents, and constructing a control simulation lab for demonstrating this capability. This presentation will begin with a discussion of the representative future power architectures that will be required for deep space exploration vehicles. The presentation then will describe how the power controller will integrate with the vehicle followed with a discussion of the autonomous power controller. Next it will describe the test setup used to evaluate the performance of the system and lastly show some of the test results. To develop the type of controller envisioned, it will be necessary to employ a detailed real-time simulation to evaluate its performance and ultimately verify its functionality.

Csank, Jeffrey↗
NASA NTRSDate not supplied

Novel Tilting Ducted-Fan Aerial Vehicle Configurations

There has been recent renewed interested in ducted-fan, powered-lift vertical takeoff and landing aircraft vehicles for uninhabited aerial vehicle and urban aerial mobility aerial applications. Early work was conducted in the 1950’s to the late 1980’s into ducted-fan vehicles, especially at the time for military missions. The focus of ducted-fan research began to shift to UAV’s and personal air transportation in the 2000’s. Work in the early 2000’s fostered interest into ducted-fan aerial vehicles for vertical lift planetary aerial vehicle missions, especially for missions to Titan, a moon of Saturn. For example, early work at NASA Ames conducted the first known investigation into oval ducts (with internal tandem fans) to be used for these aerial vehicles. The use of twin oval ducts (with internal tandem fans) allowed the use of quadrotor-style rotor rpm control for vehicle trim (in hover, for transition to high-speed forward flight the addition of a tilt-actuator to pitch the twin oval ducts forward to be aligned with the freestream needed to be added to the control approach. This current study explores open-rotor, single isolated ducted-fan, and full vehicle configuration aerodynamic performance for hover, transition, and cruise regimes for novel tilting ducted-fan aerial vehicle configurations. The objective of this study is to better understand the design aerodynamics trade space for noncircular tilting ducted-fans. The primary analysis tool used in this paper is the mid-fidelity computational fluid dynamics RotCFD tool. Several interesting and largely unexplored rotor-on-rotor (or fan-on-fan), duct-on-rotor, rotor- on-duct, and duct-on-airframe are examined in this paper. Many of these aerodynamic interactions are the key to overall aerial vehicle performance. Limited parametric sweeps of rotor-to-rotor spacing (and, therefore, sizing and shape of the enveloping ducts) for the various duct configurations will also be performed. The trade-offs between duct thrust augmentation in hover versus improved transition controllability versus improved cruise L/D will be discussed for various novel duct configurations. These ducted-fan configurations include oval ducts, ‘figure-eight’ ducts, and ‘B-shaped’ ducts, among others.

Ducted-Fan↗
DOE OSTI2023

Toward Consistent High-Fidelity Quantum Learning on Unstable Devices via Efficient In-Situ Calibration

In the near-term noisy intermediate-scale quantum (NISQ) era, high noise will significantly reduce the fidelity of quantum computing. What's worse, recent works reveal that the noise on quantum devices is not stable, that is, the noise is dynamically changing over time. This leads to an imminent challenging problem: At run-time, is there a way to efficiently achieve a consistent high-fidelity quantum system on unstable devices? To study this problem, we take quantum learning (a.k.a., variational quantum algorithm) as a vehicle, which has a wide range of applications, such as combinatorial optimization and machine learning. A straightforward approach is to optimize a variational quantum circuit (VQC) with a parameter-shift approach on the target quantum device before using it; however, the optimization has an extremely high time cost, which is not practical at run-time. To address the pressing issue, in this paper, we proposed a novel quantum pulse-based noise adaptation framework, namely QuPAD. In the proposed framework, first, we identify that the CNOT gate is the fidelity bottleneck of the conventional VQC, and we employ a more robust parameterized multi-qubit gate (i.e., Rzx gate) to replace CNOT gate. Second, by benchmarking Rzx gate with different parameters, we build a fitting function for each coupling qubit pair, such that the deviation between the theoretic output of Rzx gate and its on-device output under a given pulse amplitude and duration can be efficiently predicted. On top of this, an evolutionary algorithm is devised to identify the pulse amplitude and duration of each Rzx gate (i.e., calibration) and find the quantum circuits with high fidelity. Experiments show that the runtime on quantum devices of QuPAD with 8–10 qubits is less than 15 minutes, which is up to 270 x faster than the parameter-shift approach. In addition, compared to the vanilla VQC as a baseline, QuPAD can achieve 59.33% accuracy gain on a classification task, and average 66.34% closer to ground state energy for molecular simulation.

Hu, Zhirui↗
DOE OSTI2023

Machine Learning-Based Model Predictive Control of Two-Time-Scale Systems

In this study, we present a general form of nonlinear two-time-scale systems, where singular perturbation analysis is used to separate the dynamics of the slow and fast subsystems. Machine learning techniques are utilized to approximate the dynamics of both subsystems. Specifically, a recurrent neural network (RNN) and a feedforward neural network (FNN) are used to predict the slow and fast state vectors, respectively. Moreover, we investigate the generalization error bounds for these machine learning models approximating the dynamics of two-time-scale systems. Next, under the assumption that the fast states are asymptotically stable, our focus shifts toward designing a Lyapunov-based model predictive control (LMPC) scheme that exclusively employs the RNN to predict the dynamics of the slow states. Additionally, we derive sufficient conditions to guarantee the closed-loop stability of the system under the sample-and-hold implementation of the controller. A nonlinear chemical process example is used to demonstrate the theory. In particular, two RNN models are constructed: one to model the full two-time-scale system and the other to predict solely the slow state vector. Both models are integrated within the LMPC scheme, and we compare their closed-loop performance while assessing the computational time required to execute the LMPC optimization problem.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2024

Agent-based simulations of shared automated vehicle operations: reflecting travel-party size, season and day-of-week demand variations

Here, this paper explores the effects of day of week and season of year demand variations for shared rides, along with realistic travel party sizes, on shared autonomous vehicle (SAV) services across the Austin, Texas region. Using the agent-based POLARIS program, synthetic person-trips that reflect travel-party size (from one to four persons) and demand variations over days and months, as evident in the National Household Travel Survey data were simulated in each scenario over a 24 h travel day. Results show that realistic party sizes can bring considerable changes to SAV fleet performance, including up to 8.5% higher service rates (number of requests accepted within 15 min), 5 min shorter journey times (wait time + travel time), 28% higher vehicle occupancies on weekends, and roughly 4% lower empty fleet VMT. Weekend travel is most impacted by season of year, with weekday travel patterns looking more uniform (thanks to work and school trips). Various performance metrics for the Austin network, like total and empty VMT, change by up to 30% when considering realistic variations in party size and time of year. This paper underscores the value of recognizing day-to-day and month-to-month variations in travel demand, and the importance of agent-based model equations to reflect travel-party size. Such realism can help quantify SAV seat occupancies more accurately, highlighting the importance of shared mobility. However, it also creates demand and supply issues for operators that now need more information on party size to manage dynamic ride-sharing, or those that may wish to shift their fleet vehicles to other regions for special events to protect profits while offering reasonable wait times to customers throughout the year.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2023

Evolution of the Internal Climate Modes under Future Warming

Abstract Climate modes play an important role in weather and climate variability over multiple spatial and temporal scales. This research assesses Earth system model (ESM) projections of the spatiotemporal characteristics of key internal climate modes (NAM, SAM, PNA, ENSO, PDO, and AMO) under high (SSP585) and low (SSP126) radiative forcing scenarios and contextualizes those projections using historical fidelity. Time series analyses are used to assess trends and mode phase characteristics are summarized for the historical period and for the end of the twenty-first century. Spatial patterns are compared to infer morphological changes. Shifts in the power spectra are used to examine changes in variability at subannual, interannual, and interdecadal scales. Changes in time-lagged correlations are used to capture the evolution of first-order interactions. While differences in historical skill are predominantly ESM dependent, changing mode characteristics in a warmer climate also exhibit variability between individual ensemble realizations. NAM, SAM, and ENSO tend to evolve toward increased prevalence of the positive phase up to 2100 across the multimodel ensemble while the PNA and PDO exhibit little trend but increasing phase intensity. AMO characteristics are shown to depend on the method used to remove the external signal. ESMs that show higher historical fidelity tend to show more modest changes in those modes under global nonstationarity. Changes in mode interactions are found to be highly ESM dependent but exhibit broadly similar behavior to historical relationships. These findings have implications for our understanding of internal variability and make clear that the choice of ESM, and even the ESM realization, matters for applications of climate projections. Significance Statement Internal modes of variability are important to understand due to their impact on local, regional, and global weather and climate patterns. Future climate changes will not only be affected by the variability arising from these modes, but the modes will themselves change in response to the changing climate. Spatial and temporal aspects of the modes are assessed from projections of future climate and related to how well they are captured in the historical climate. This yields some measure of confidence in the changes exhibited by the models. In most cases, when historically skillful models exhibit changes that are different from those produced by less skillful models, they tend to produce more modest changes. These results, as well as the variability between model outcomes, mean decisions on which ESM to use for projections of the future climate matter significantly.

Meteorology & Atmospheric Sciences↗
NASA NTRS2008

Increasing the Cost-efficiency of the DSN

JPL has operated the Deep Space Network (DSN) on behalf of NASA since the 1960's. Over the last two decades, the DSN budget has generally declined in real-year dollars while the aging assets required more attention, and the missions became more complex. As a result, the budget has been increasingly consumed by Operations and Maintenance (O and M), significantly reducing the funding wedge available for technology investment and for enhancing the DSN capability and capacity. Responding to this budget squeeze, the DSN launched an effort to improve the cost-efficiency of the O and M. In this paper we: Analyze the components of O&M. We note for example that, for the DSN, less than 20% of the staff engage in the traditional human-in-front-a-console role, so any effort to increase the cost efficiency must go beyond reducing the number of "Real-time operators." Explain the underlying organizational and cultural structures. Any cost-efficiency activities changes either accept, or carefully modify these structures. For example, the DSN O&M is based on the concept that there are three nearly identical antenna complexes separated by approximately 1200 in latitude and that each antenna complex is operated by a different contractor (driven by international agreements). Explore planned changes in the customer interface, e.g. web-based automated scheduling, and the processes required for a transition. Changes have to be evaluated in the larger end-to-end context, e.g. do the changes provide a net cost-efficiency for the DSN and the missions, or do they merely shift cost from the DSN to the missions. Consider possible significant changes in real-time pass management, e.g. full-remoting of operations, and lights-dim operations, while maintaining (or improving) the performance metrics of the DSN. Investigate how procedural and administrative changes could increase cost-efficiency, in conjunction with changes in the customer interfaces and real-time pass management. Examples would be handling of inter-governmental agreements, improved sharing of resources with other agencies, and better use of commercial (rather than government) resources

Deep Space Network (DSN)↗
NASA NTRS1999

A LIS Validation Study at the KSC-ER using LDAR and Field Mill Data

The chance of having the TRMM satellite pass over east central Florida when there is lightning over the NASA Kennedy Space Center (KSC) and USAF Eastern Range (ER) is small; however, such a condition did occur on September 21, 1998 (Day 264). Starting at about 20:40 GMT, the Lightning Imaging Sensor (LIS) reported 5 flashes during a 90 second interval that the KSC-ER was within the sensor field of view. Ground-based instrumentation, the Lightning Detection and Ranging (LDAR) system and a network of electric field mills (FM), detected 6 flashes in the same interval. In this paper, we will compare the times and locations of the optical pulses that were detected by LIS with the times and locations of RF sources (LDAR) and the charges that were deposited by the flash (FM network). We will show that LIS responded to all flashes that the LDAR and FM network detected; however, two discharges that were separated by less than 1 second in time and by about 10 km in space were grouped as one flash by the LIS data processing algorithm. In spite of the fact that all flashes occurred near the edge of the LIS field of view, the locations of the LIS events were consistent with both the LDAR and FM locations (the latter are usually within 1-2 kilometers of each other and often are co-located). Two of the 5 flashes reported by LIS were shifted north by about 8 km from the corresponding LDAR and FM locations. The LIS flash times tended to be after the first LDAR pulse was detected and before the last, and the integrated light signal (per LIS event) was surprisingly constant over the 5 flashes that were detected by LIS. In the future, we plan to study more correlated events and will try to determine whether and how the LIS light signal is related to the charge transfer in the flash and/or the number and spatial extent of RF sources.

Koshak, William J.↗
NASA NTRS1999

Relationship of endogenous circadian melatonin and temperature rhythms to self-reported preference for morning or evening activity in young and older people

BACKGROUND: Morningness-eveningness refers to interindividual differences in preferred timing of behavior (i.e., bed and wake times). Older people have earlier wake times and rate themselves as more morning-like than young adults. It has been reported that the phase of circadian rhythms is earlier in morning-types than in evening types, and that older people have earlier phases than young adults. These changes in phase have been considered to be the chronobiological basis of differences in preferred bed and wake times and age-related changes therein. Whether such differences in phase are associated with changes in the phase relationship between endogenous circadian rhythms and the sleep-wake cycle has not been investigated previously. METHODS: We investigated the association between circadian phase, the phase relationship between the sleep-wake cycle and circadian rhythms, and morningness-eveningness, and their interaction with aging. In this circadian rhythm study, 68 young and 40 older subjects participated. RESULTS: Among the young subjects, the phase of the melatonin and core temperature rhythms occurred earlier in morning than in evening types and the interval between circadian phase and usual wake time was longer in morning types. Thus, while evening types woke at a later clock hour than morning types, morning types actually woke at a later circadian phase. Comparing young and older morning types we found that older morning types had an earlier circadian phase and a shorter phase-wake time interval. The shorter phase-waketime interval in older "morning types" is opposite to the change associated with morningness in young people, and is more similar to young evening types. CONCLUSIONS: These findings demonstrate an association between circadian phase, the relationship between the sleep-wake cycle and circadian phase, and morningness-eveningness in young adults. Furthermore, they demonstrate that age-related changes in phase angle cannot be attributed fully to an age-related shift toward morningness. These findings have important implications for understanding individual preferences in sleep-wake timing and age-related changes in the timing of sleep.

Non-NASA Center↗
NASA NTRS2022

Mars 2020 Entry, Descent, and Landing as Observed by Radio Science Techniques at UHF and X-band Frequencies

On February 18, 2021, NASA’s Mars 2020 Rover “Perseverance” conducted the Entry, Descent, and Landing (EDL) sequence to land safely on the surface of Mars at Jezero Crater. Due to the criticality of the EDL sequence, redundant telecommunications strategies were utilized to observe the event. The rover transmitted an X-band (8.4 GHz) signal encoded with Multiple Frequency Shift Keying tones direct-to-Earth and a UHF (401.5 MHz) signal with 8 kbps encoded telemetry to orbiters, which relayed the signal back to Earth at X-band. NASA’s Deep Space Network complexes at Goldstone, California and Madrid, Spain received the direct-to-Earth X-band signal. Two of the largest steerable radio telescopes in the world, the 100-meter Green Bank Telescope in West Virginia and the Effelsberg 100-meter Radio Telescope in Germany also received the UHF carrier signal on Earth. During the EDL event, full spectrum recordings of the UHF and X-band signals were captured at these observatories using open-loop receivers. Real-time and post-processing signal analysis to determine power level, received frequency, and Doppler shift allowed determination of the spacecraft’s health and safety state during critical sequences, including event detection such as atmospheric entry, plasma blackouts, and parachute deployment. Simultaneous observations of the UHF and X-band radio links allow for redundancy in the event of a fault and greatly improve confidence in Doppler event detection.

Gladden, Roy↗
NASA NTRS1991

Transcapillary fluid shifts in tissues of the head and neck during and after simulated microgravity

To understand the mechanism, magnitude, and time course of facial puffiness that occurs in microgravity, seven male subjects were tilted 6 degrees head down for 8 hr, and all four Starling transcapillary pressures were directly measured before, during , and after tilt. Head-down tilt (HDT) caused facial edema and a significant elevation of microvascular pressures measured in the lower lip. Subcutaneous and intramuscular interstitial fluid pressures in the neck also increased as a result of HDT, while interstitial fluid colloid osmotic pressures remained unchanged. Plasma colloid osmotic pressures dropped significantly after 4 hr of HDT, suggesting a transition from fluid filtration to absorption in capillary beds between the heart and feet during HDT. After 4 hr of seated recovery from HDT, microvascular pressures remained significantly elevated by 5 to 8 mm Hg above baseline values despite a significant HDT diuresis and the orthostatic challenge of an upright, seated posture. During the control (baseline) period, urine output was 46.7 ml/hr; during HDT, it was 126.5 ml/hr.

Hargens, A. R.↗
NASA NTRSDate not supplied

Earth-Independent Medical Operations (EIMO) Concept of Operations

In contrast to the current crew health paradigm for low-Earth orbit and Lunar missions, which depends on real-time communication with Mission Control, deep-space exploration missions will require a significant shift in medical operations. This shift is driven by the constraints of operating at a considerable distance from Earth, such as resource limitations—lack of resupply, restricted mass, power, volume, and data—as well as communication delays and the inability to evacuate back to Earth during emergencies. To move toward a more self-reliant medical model, a strategy is needed to gradually increase space-based crew autonomy and reduce risks to mission success in the challenging environment of deep space. This transformative change, known as "Earth-Independent Medical Operations" (EIMO), explores the gradual transfer of medical care and decision-making from Earth-based support to space-based systems. The goal of this transition is to enhance astronaut health and performance while minimizing mission risks. EIMO requires the development of a medical system that integrates seamlessly with mission planning, vehicle and spacesuit design, and data architecture. This integration is crucial for building a robust medical infrastructure that not only safeguards astronaut well-being but also ensures overall mission success. The Human Research Program (HRP) Exploration Medical Capability (ExMC) Element has revised the EIMO model-based Concept of Operations (ConOps) which outlines an initial vision for EIMO. The ConOps, which is built on the stakeholders’ need, system goals, and objectives (NGOs), presents an array of in-mission scenarios that span a wide range of medical conditions demonstrating the system’s capabilities from basic to complex events. Developed by a multidisciplinary team of systems engineers, scientists, and clinicians within ExMC, the ConOps revision includes two new scenarios(Barotrauma and Self-Medical Management and Behavioral Health and Chronic Medical Care), and implementation of findings from EIMO technical interchange meetings that focused on data and training. The envisioned EIMO Medical System (MS) operates as a system of systems, gathering data from various sources such as reference databases, real-time wearable sensors, point-of-care diagnostics, and environmental controls. The MS also incorporates advanced training tools to support autonomous medical care, assisting the Crew Medical Officer (CMO) during medical events where Ground Support is either unavailable or communication-delayed beyond practicality. Furthermore, MS functions and capabilities were decomposed from the scenarios to establish foundational requirements for EIMO and traced to the NASA Spaceflight Human-System Standard(NASA-STD-3001, Volumes 1 and 2). These traces were performed to gain insights on the alignment of EIMO requirements with the NASA standard. This work serves as an initial recommendation to increase crew autonomy gradually and safely for Mars missions and future deep-space exploration.

medical system↗