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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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NASA NTRS2002

Efficient Low Dissipative High Order Schemes for Multiscale MHD Flows

Accurate numerical simulations of complex multiscale compressible viscous flows, especially high speed turbulence combustion and acoustics, demand high order schemes with adaptive numerical dissipation controls. Standard high resolution shock-capturing methods are too dissipative to capture the small scales and/or long-time wave propagations without extreme grid refinements and small time steps. An integrated approach for the control of numerical dissipation in high order schemes for the compressible Euler and Navier-Stokes equations has been developed and verified by the authors and collaborators. These schemes are suitable for the problems in question. Basically, the scheme consists of sixth-order or higher non-dissipative spatial difference operators as the base scheme. To control the amount of numerical dissipation, multiresolution wavelets are used as sensors to adaptively limit the amount and to aid the selection and/or blending of the appropriate types of numerical dissipation to be used. Magnetohydrodynamics (MHD) waves play a key role in drag reduction in highly maneuverable high speed combat aircraft, in space weather forecasting, and in the understanding of the dynamics of the evolution of our solar system and the main sequence stars. Although there exist a few well-studied second and third-order high-resolution shock-capturing schemes for the MHD in the literature, these schemes are too diffusive and not practical for turbulence/combustion MHD flows. On the other hand, extension of higher than third-order high-resolution schemes to the MHD system of equations is not straightforward. Unlike the hydrodynamic equations, the inviscid MHD system is non-strictly hyperbolic with non-convex fluxes. The wave structures and shock types are different from their hydrodynamic counterparts. Many of the non-traditional hydrodynamic shocks are not fully understood. Consequently, reliable and highly accurate numerical schemes for multiscale MHD equations pose a great challenge to algorithm development. In addition, controlling the numerical error of the divergence free condition of the magnetic fields for high order methods has been a stumbling block. Lower order methods are not practical for the astrophysical problems in question. We propose to extend our hydrodynamics schemes to the MHD equations with several desired properties over commonly used MHD schemes.

Sjoegreen, Bjoern↗
NASA NTRS2015

Essentials for Team Based Rehearsals and the Differences Between Earth Orbiting and Deep Space Missions

The mission readiness environment is where spacecraft and ground systems converge to form the entire as built flight system for the final phase of operationally-themed testing. For most space missions, this phase starts between nine to twelve months prior to the planned launch. In the mission readiness environment, the goal is to perform sufficient testing to exercise the flight teams and systems through all mission phases in order to demonstrate that all elements are ready to support. As part of the maturation process, a mission rehearsal program is introduced to focus on team processes within the final flight system, in a more realistic operational environment. The overall goal for a mission rehearsal program is to: 1) ensure all flight system elements are able to meet mission objectives as a cohesive team; 2) reduce the risk in space based operations due to deficiencies in people, processes, procedures, or systems; and 3) instill confidence in the teams that will execute these first time flight activities. A good rehearsal program ensures critical events are exercised, discovers team or flight system nuances whose impact were previously unknown, and provides a real-time environment in which to interact with the various teams and systems. For flight team members, the rehearsal program provides experience and training in the event of planned (or unplanned) flight contingencies. To preserve the essence for team based rehearsals, this paper will explore the important elements necessary for a successful rehearsal program, document differences driven by Earth Orbiting (Aqua, Aura, Suomi-National Polar-orbiting Partnership (NPP)) and Deep Space missions (New Horizons, Mars Atmosphere and Volatile EvolutioN (MAVEN)) and discuss common challenges to both mission types. In addition, large scale program considerations and enhancements or additional steps for developing a rehearsal program will also be considered. For NASA missions, the mission rehearsal phase is a key milestone for predicting and ensuring on-orbit success.

Gomez-Rosa, Carlos↗
NASA NTRS2018

International Space Station Operational Experience and Its Impacts on Future Mission Supportability

Operational experience gained on the International Space Station (ISS) has enabled significant improvements in failure rate estimates for various Orbital Replacement Units (ORUs). These improved estimates, in turn, allow more efficient and accurate spare parts allocations for future missions, enabling significant reductions in both logistics mass and risk. This paper examines the value of ISS experience to date in terms of its impact on supportability for future missions. A supportability model is presented that assesses the spares required as a function of mission endurance and risk, taking into account uncertainty in failure rate estimates. Changes in ISS Environmental Control and Life Support (ECLSS) ORU failure rate estimates are described and discussed, both in terms of the overall population of ORUs and the evolution of failure rate estimates over time for a particular item. The value of those updated failure rate estimates is assessed by calculating the estimated spares mass requirements for two cases, using the initial, pre-ISS estimates and using the estimates informed by on-orbit experience. Hidden risk resulting from underestimated failure rates is also assessed. These results indicate that, for a 1,200-day Mars mission, ISS experience has enabled a 3.9 t to 6.0 t reduction in ECLSS spares mass required and uncovered failure rate underestimates that would have resulted in an order of magnitude increase in risk had they not been discovered and corrected. The implications of these results for system development and mission planning are discussed, including approaches to accelerate the rate of failure rate refinement and the risks associated with making changes or introducing new systems. Overall, test time is a critical factor that must be carefully considered in system development, and new systems must budget appropriate time for testing in a relevant environment or accept higher risk and logistics requirements on future missions.

Owens, Andrew C.↗
NASA NTRS2014

Misconceptions of Electric Propulsion Aircraft and Their Emergent Aviation Markets

Over the past several years there have been aircraft conceptual design and system studies that have reached conflicting conclusions relating to the feasibility of full and hybrid electric aircraft. Some studies and propulsion discipline experts have claimed that battery technologies will need to improve by 10 to 20 times before electric aircraft can effectively compete with reciprocating or turbine engines. However, such studies have approached comparative assessments without understanding the compelling differences that electric propulsion offers, how these technologies will fundamentally alter the way propulsion integration is approached, or how these new technologies can not only compete but far exceed existing propulsion solutions in many ways at battery specific energy densities of only 400 watt hours per kilogram. Electric propulsion characteristics offer the opportunity to achieve 4 to 8 time improvements in energy costs with dramatically lower total operating costs, while dramatically improving efficiency, community noise, propulsion system reliability and safety through redundancy, as well as life cycle Green House Gas emissions. Integration of electric propulsion will involve far greater degrees of distribution than existing propulsion solutions due to their compact and scale-free nature to achieve multi-disciplinary coupling and synergistic integration with the aerodynamics, highlift system, acoustics, vehicle control, balance, and aeroelasticity. Appropriate metrics of comparison and differences in analysis/design tools are discussed while comparing electric propulsion to other disruptive technologies. For several initial applications, battery energy density is already sufficient for competitive products, and for many additional markets energy densities will likely be adequate within the next 7 years for vibrant introduction. Market evolution and early adopter markets are discussed, along with the investment areas that will fill technology gaps and create opportunities for the effective, near-term electric aircraft products. Without understanding both the context of how electric propulsion will integrate into the vehicle system, and evolve into the market place it is likely that electric propulsion will continue to be misunderstood.

Moore, Mark D.↗
NASA NTRS1999

How Does the Global-Scale Atmosphere Circulation Produce Clouds?

Although clouds are produced by "micro-scale" processes, these processes operate as a response to global-scale atmospheric motions to produce the complex geographic distribution of clouds on Earth. One way to attack this larger-scale problem is to combine global-scale satellite observations of cloud property variations with global-scale determinations of the atmospheric circulation. Such a global data analysis can be used to describe the mean characteristics of clouds and their variations for comparison with global circulation models, to identify systematic relations among observed cloud properties and atmospheric motions, or to estimate, directly, the derivative relations of the processes at work using statistical life-cycle-composites of cloud system evolution. Another approach is to find what characteristics of the global atmospheric circulation are revealed in observed global-scale cloud variations. For the first time this type of analysis is possible with the advent of global, satellite-based cloud (ISCCP), precipitation (microwave-based), and water vapor (merged infrared and microwave) datasets, together with global wind datasets (ECMWF and NCEP re-analyses), all of which resolve features at least down to the upper end of the mesoscale and cover more than a decade. We report on some preliminary attempts to identify quantitative relationships between atmospheric motions and cloud properties that are relevant to cloud processes. Three examples are given: (1) cloud variations at the smallest scales and what they reveal about the nature of small-scale turbulence in the atmospheric boundary layer, (2) cloud variations at "moderate" weather-scales and what they reveal about meteorological storm systems, and (3) cloud variations at the largest scales and what they indicate about interannual variations of climate.

Rossow, William B.↗
NASA NTRS2019

Deep Learning Method for Detecting Precursors to Adverse Events

With the recent advancements in Deep Learning methods, the ability to model large complex heterogeneous data sets are fundamentally changing industry and research. Coupled with hardware improvements, and ease of implementation, a wide variety of deep neural network architectures can quickly be developed to solve a sweeping range of problems such as: object detection in images, automatic healthcare diagnosis using heterogenous data sources, real time language translating and sentence prediction, upscaling low resolution images, and forecasting of multivariate timeseries. Generally, many of these architectures outperform classical machine learning approaches in their respective tasks, however, this typically comes at a cost of interpretability. These black box algorithms generally suffer from lack of transparency in both model complexity as well as the rationale behind the prediction. This lack of comprehension, is driving an emerging area of interest in “Explainable AI”. An algorithm called: “Deep Temporal Multiple Instance Learning”1 was a recently developed to identify precursors to adverse events and has been applied in the aviation domain. The deep learning architecture is designed to capture the evolution of the probability of the outcome over the time preceding the adverse event using a multiple instance learning approach as illustrated in Figure 1. Precursors are defined when the probability of the event has exceeded a threshold at some point in the timeseries, at which point, a sensitivity analysis is performed to determine contributing factors. The contributing factors are used to explain and define the precursor during the periods where the probability score is high. The identified contributing factors are then presented to subject matter experts to provide objective insights into the leading factors associated with the particular adverse event. The algorithm has been tested on flight data from a commercial airline and has the ability to discover precursors to known adverse events that take the form of safety critical operations, such as unstable approach events on final approach. Apart from detecting precursors to adverse events, the converse can also be leveraged to discover corrective actions. These positive actions manifest themselves as periods in the timeseries when the precursor score has been lowered from an elevated state; meaning that if the system had been left uncorrected, it would have eventually reached the adverse event state. Characterizing these state changes can help identify successful interventions that may not have been known before. Policy makers and procedure designers can use this additional knowledge to craft more safety and efficient resilient procedures for future operations and therefore improve the overall performance of the National Airspace.

Matthews, Bryan L.↗
NASA NTRS2006

Temporal Evolution of the Nanostructure and Phase Compositions in a Model Ni-Al-Cr Alloy

In a Ni-5.2 Al-14.2 Cr at.% alloy with moderate solute supersaturations and a very small gamma/gamma prime lattice parameter misfit, the nanostructural and compositional pathways during gamma prime(L12) precipitation at 873 K are investigated using atom-probe tomography, conventional transmission electron microscopy, and hardness measurements. Nucleation of high number densities (N(sub v) greater than 10(sup 23) per cubic meters) of solute-rich precipitates (mean radius = [R] = 0.75 nm), with a critical nucleus composition of Ni-18.3 plus or minus 0.9 Al-9.3 plus or minus 0.7 Cr at.%, initiates between 0.0833 and 0.167 h. With increasing aging time (a) the solute concentrations decay in spheroidal precipitates ([R] less than 10 nm); (b) the observed early-stage coalescence peaks at maximum N(sub v) in coincidence with the smallest interprecipitate spacing; and (c) the reaction enters a quasi-stationary regime where growth and coarsening operate concomitantly. During this quasi-stationary regime, the c (face-centered cubic)-matrix solute supersaturations decay with a power-law dependence of about -1/3, while the dependencies of [R] and N(sub v) are 0.29 plus or minus 0.05 and -0.64 plus or minus 0.06 at a coarsening rate slower than model predications. Coarsening models allow both equilibrium phase compositions to be determined from the compositional measurements. The observed early-stage coalescence is discussed in further detail.

Sudbrack, Chantal K.↗
NASA NTRS1990

Observation simulation experiments with regional prediction models

Research efforts in FY 1990 included studies employing regional scale numerical models as aids in evaluating potential contributions of specific satellite observing systems (current and future) to numerical prediction. One study involves Observing System Simulation Experiments (OSSEs) which mimic operational initialization/forecast cycles but incorporate simulated Advanced Microwave Sounding Unit (AMSU) radiances as input data. The objective of this and related studies is to anticipate the potential value of data from these satellite systems, and develop applications of remotely sensed data for the benefit of short range forecasts. Techniques are also being used that rely on numerical model-based synthetic satellite radiances to interpret the information content of various types of remotely sensed image and sounding products. With this approach, evolution of simulated channel radiance image features can be directly interpreted in terms of the atmospheric dynamical processes depicted by a model. Progress is being made in a study using the internal consistency of a regional prediction model to simplify the assessment of forced diabatic heating and moisture initialization in reducing model spinup times. Techniques for model initialization are being examined, with focus on implications for potential applications of remote microwave observations, including AMSU and Special Sensor Microwave Imager (SSM/I), in shortening model spinup time for regional prediction.

Diak, George↗
NASA NTRS1988

The 2.5-12 micrometers spectrum of comet Halley from the IKS-VEGA experiment

The infrared instrument IKS flown on board the VEGA space probes was designed for the detection of emission bands of parent molecules, and for a measurement of the size and temperature of the thermal emitting nuclear region. The instrument had three channels with cooled detectors: an "imaging channel" designed to modulate the signal of the nucleus and two spectroscopic channels operating at 2.5-5 and 6-12 micrometers, respectively, equipped with circular variable filters of resolving power approximately 50. This paper presents and discusses the results from the spectral channels. On VEGA 1, usable spectra were obtained at distances D from the comet nucleus ranging from 250,000 to 40,000 km corresponding to fields of view 4000 and 700 km in diameter, respectively. The important internal background signal caused by the instrument itself, which could not be cooled, had to be eliminated. Since no sky chopping was performed, we obtain difference spectra between the current spectrum and a reference spectrum with little or no cometary signal taken at the beginning of the observing sequence (D approximately 200,000 km). Final discrimination between cometary signal and instrumental background is achieved using their different time evolution, since the instrumental background is proportional to the slow temperature drift of the instrument, and the cometary signal due to parent molecules or dust grains is expected to vary in first order as D-1. The 2.5-5 micrometers IKS spectra definitely show strong narrow signals at 2.7 and 4.25 micrometers, attributed to the nu 3 vibrational bands of H2O and CO2, respectively, and a broader signal in the region 3.2-3.5 micrometers, which may be attributed to CH-bearing molecules. All these signals present the expected D-1 intensity variation. Weaker emission features at 3.6 and 4.7 micrometers could correspond to the nu 1 and nu 5 bands of H2CO and the (1 - 0) band of CO, respectively. Molecular production rates are derived from the observed emissions, assuming that they are due to resonance fluorescence excited by the Sun's infrared radiation. For the strong bands of H2O and CO2, the rovibrational lines are optically thick, and radiative transfer is taken into account. We derive production rates, at the moment of the VEGA 1 flyby, of approximately 10(30) sec-1 for H2O, approximately 2.7 x 10(28) sec-1 for CO2, approximately 5 x 10(28) sec-1 for CO, and 4 x 10(28) sec-1 for H2CO, if attributions to CO and H2CO are correct. The production rate of carbon atoms in CH-bearing molecules is approximately 9 x 10(29) sec-1 assuming fluorescence of molecules in the gas phase, but could be much less if the 3.2-3.5 micrometers emission is attributed to C-H stretch in polycyclic aromatic hydrocarbons or small organic grains. In addition, marginal features are present at 4.85 and 4.45 micrometers, tentatively attributed to OCS and molecules with the CN group, respectively. Broad absorption at 2.8-3.0 micrometers, as well as a narrow emission at 3.15 micrometers, which follow well the D-1 intensity variation, might be due to water ice. Emission at 2.8 micrometers is also possibly present, and might be due to OH created in vibrationally excited states after water photodissociation. The 6-12 micrometers spectrum does not show any molecular emission, nor emission in the 7.5-micrometers region. The spectrum is dominated by silicate emission showing a double structure with maxima at 9.0 and 11.2 micrometers, which suggests the presence of olivine.

NASA Discipline Number 52-10↗
NASA NTRS2000

A Comparison of the Automated Meteorological Profiling System High Resolution Flight Element to the Kennedy Space Center 50 MHz Doppler Wind Profiler

Wind profile measurement and the simulation of aerodynamic loads on a launch vehicle play an important role in determining launch capability and post launch assessment of the vehicle's performance. To date, all United States range certified wind profile measurement systems have been based on balloon tracking. Since the 1960's, the standard used by the National Aeronautics and Space Administration and the Air Force at the Cape Canaveral Air Station (CCAS) for detailed wind profile measurements has been the radar tracked, aerodynamically stabilized Jimsphere balloon system. Currently, the Air Force is nearing certification and operational implementation of the Automated Meteorological Profiling System (AMPS) at CCAS and Vandenburg Air Force Base (VAFB). AMPS uses the Global Positioning System for tracking the Jimsphere balloon. It is anticipated that the AMPS/Jimsphere, named the High Resolution Flight Element (HRFE), will have equivalent, or better resolution than the radar tracked Jimsphere, especially when the balloon is far downrange, at a low elevation angle. By the 1980's, the development of Doppler Wind Profilers (DWP) had become sufficiently advanced to justify an experimental measurement program at Kennedy Space Center (KSC). In 1989 a 50 MHz DWP was installed at KSC. In principal, the 50 MHz DWP has the capability to track the evolution of wind profile dynamics within 5 minutes of a launch. Because of fundamental differences in the measurement technique, there is a significant time and space differential between 50 MHz DWP and HRFE wind profiles. This paper describes a study to quantify these differences from a sample of 50 MHz DWP/HRFE pairs obtained during the AMPS certification test program.

Roberts, Barry C.↗
NASA NTRS1974

Barium cloud evolution and striation formation in the magnetospheric release on September 21, 1971

The joint NASA-Max Planck Institute Barium Ion Cloud (BIC) Experiment on September 21, 1971 involved the release of 1.7 kg of neutral barium at an altitude of 31,500 km at a latitude of 6.93 deg N. and a longitude of 74.40 deg W. A theoretical model describing the barium neutral cloud expansion and the ion cloud formation is developed. The mechanism of formation of the striational features observed in the release is also discussed. Two candidate instabilities, which may contribute to striation formation, are examined. The drift instability stemming from the outwardly directed drag force exerted on the ions by the outstreaming neutrals is rejected on the grounds that the ion density is too low during the collision-dominated phase of the cloud expansion to support this kind of instability. The joint action of Rayleigh-Taylor and flute instabilities plausibly accounts for the observed striational structure. This same mechanism may well be operative at times of sudden injection of plasma into the inner magnetosphere during geomagnetic storms and may thus contribute to the formation of field-alined inhomogeneities which serve as whistler ducts.

Adamson, D.↗
NASA NTRS1977

The micrometeoroid complex and evolution of the lunar regolith

Monte Carlo-based computer calculations, as well as analytical approaches utilizing probabilistic arguments, were applied to gain insight into the principal regolith impact processes and their resulting kinetics. Craters 10 to 1500 m in diameter are largely responsible for the overall growth of the regolith. As a consequence the regolith has to be envisioned as a complex sequence of discrete ejecta blankets. Such blankets constitute first-order discontinuities in the evolving debris layer. The micrometeoroid complex then operates intensely on these fresh ejecta blankets and accomplishes only in an uppermost layer of approximately 1-mm thickness. The absolute flux of micrometeoroids based on lunar rock analyses averaged over the past few 10 to the 6th power years is approximately an order of magnitude lower than presentday satellite fluxes; however, there is indication that the flux increased in the past 10 to the 4th power years to become compatible with the satellite data. Furthermore, there is detailed evidence that the micrometeoroid complex existed throughout geologic time.

Horz, F.↗
NASA NTRS1988

Lunar settlements--a socio-economic outlook

The primary ingredient in a Lunar Settlement Program is the people. At the very high cost that will be required to transport, maintain and supply the people who will staff the Lunar operation, it is important to do everything possible to ensure their continued effectiveness in such an isolated, confined, and barren environment. This paper will attempt to identify the issues involved in providing for effective human performance in Lunar Settlements. The approach to be used will be contextual, and thus will not only examine the facets of the Lunar Settlement itself, but will also look at the organizational elements and the design and development processes used in project management from the point of view of long term success and cost effectiveness. The approach will also attempt to look at the Lunar Settlement "in time" as it is connected to events and experiences as they will evolve from the Space Station to Lunar Settlements. Finally, the approach will be contextual in the range of disciplines considered and their impact on planning, evolution, and activities in the entire process of Lunar Settlement. We will hope that Lunar settlers will be able to work and live as effective team members, and to make that possible, the designers, developers, builders, and managers must also function as a coherent team working together to bring about a common goal.

Space Flight/economics/organization & administrati↗
NASA NTRS2010

The COSPIX Mission: Focusing on the Energetic and Obscured Universe

Tracing the formation and evolution of all supermassive black holes, including the obscured ones, understanding how black holes influence their surroundings and how matter behaves under extreme conditions, are recognized as key science objectives to be addressed by the next generation of instruments. These are the main goals of the COSPIX proposal, made to ESA in December 2010 in the context of its call for selection of the M3 mission. In addition, COSPIX, will also provide key measurements on the non thermal Universe, particularly in relation to the question of the acceleration of particles, as well as on many other fundamental questions as for example the energetic particle content of clusters of galaxies. COSPIX is proposed as an observatory operating from 0.3 to more than 100 keV. The payload features a single long focal length focusing telescope offering an effective area close to ten times larger than any scheduled focusing mission at 30 keV, an angular resolution better than 20 arcseconds in hard X-rays, and polarimetric capabilities within the same focal plane instrumentation. In this paper, we describe the science objectives of the mission, its baseline design, and its performances, as proposed to ESA.

Ferrando, P.↗
NASA NTRS2011

SPASE: The Connection Among Solar and Space Physics Data Centers

The Space Physics Archive Search and Extract (SPASE) project is an international collaboration among Heliophysics (solar and space physics) groups concerned with data acquisition and archiving. Within this community there are a variety of old and new data centers, resident archives, "virtual observatories", etc. acquiring, holding, and distributing data. A researcher interested in finding data of value for his or her study faces a complex data environment. The SPASE group has simplified the search for data through the development of the SPASE Data Model as a common method to describe data sets in the various archives. The data model is an XML-based schema and is now in operational use. There are both positives and negatives to this approach. The advantage is the common metadata language enabling wide-ranging searches across the archives, but it is difficult to inspire the data holders to spend the time necessary to describe their data using the Model. Software tools have helped, but the main motivational factor is wide-ranging use of the standard by the community. The use is expanding, but there are still other groups who could benefit from adopting SPASE. The SPASE Data Model is also being expanded in the sense of providing the means for more detailed description of data sets with the aim of enabling more automated ingestion and use of the data through detailed format descriptions. We will discuss the present state of SPASE usage and how we foresee development in the future. The evolution is based on a number of lessons learned - some unique to Heliophysics, but many common to the various data disciplines.

Thieman, James R.↗
NASA NTRS1987

History of the numerical aerodynamic simulation program

The Numerical Aerodynamic Simulation (NAS) program has reached a milestone with the completion of the initial operating configuration of the NAS Processing System Network. This achievement is the first major milestone in the continuing effort to provide a state-of-the-art supercomputer facility for the national aerospace community and to serve as a pathfinder for the development and use of future supercomputer systems. The underlying factors that motivated the initiation of the program are first identified and then discussed. These include the emergence and evolution of computational aerodynamics as a powerful new capability in aerodynamics research and development, the computer power required for advances in the discipline, the complementary nature of computation and wind tunnel testing, and the need for the government to play a pathfinding role in the development and use of large-scale scientific computing systems. Finally, the history of the NAS program is traced from its inception in 1975 to the present time.

Peterson, Victor L.↗
NASA NTRS1996

High-Latitude Ionospheric Dynamics During Conditions of Northward IMF

In order to better understand the physical processes operating during conditions of northward interplanetary magnetic field (IMF), in situ measurements from the Dynamics Explorer-2 (low altitude) polar satellite and simultaneous observations from the auroral imager on the Dynamics Explorer-1 (high altitude) satellite were used to investigate the relationships between optical emissions, particle precipitation, and convective flows in the high-latitude ionosphere. Field aligned current and convective flow patterns during IMF north include polar cap arcs, the theta aurora or transpolar arc, and the 'horse-collar' aurora. The initial part of the study concentrated on the electrodynamics of auroral features in the horse-collar aurora, a contracted but thickened emission region in which the dawn and dusk portions can spread to very high latitudes, while the latter part focused on the evolution of one type of IMF north auroral pattern to another, specifically the quiet-time horse-collar pattern to a theta aurora.

Sharber, J. R.↗
NASA NTRSDate not supplied

AEGIS: Autonomous Entity Global Intelligence System for Urban Air Mobility

This paper presents a global intelligence system that synthesizes aerial vehicles’ real-time physical data, planned actions, and historical behavior into engineered data frames representing the collective state of the airspace and suitable for efficient machine learning consumption. These data frames are then learnt by a deep neural net to build a prediction model that estimates the expected evolution path of the current state, thereby identifying potential future conflicts. This approach lends itself to an automated early warning system that the aerial vehicles can implement onboard with a suitable edge computing module more efficiently and effectively than non-AI methods, and eventually take preventive or corrective measures towards self/collaborative resolution of the issues. Contrary to a centralized early warning system where all vehicles’ task-space eventually converges to a global optimum state, the presented distributed global intelligence system brings in a balance between local utility functions of each vehicle and the global operating framework. This contributes to effectively handle the potential massive scaling in urban air mobility in the near future.

Artificial Intelligence↗