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NASA NTRS2017

Lost in Translation: the Case for Integrated Testing

The building of a spacecraft is complex and often involves multiple suppliers and companies that have their own designs and processes. Standards have been developed across the industries to reduce the chances for critical flight errors at the system level, but the spacecraft is still vulnerable to the introduction of critical errors during integration of these systems. Critical errors can occur at any time during the process and in many cases, human reliability analysis (HRA) identifies human error as a risk driver. Most programs have a test plan in place that is intended to catch these errors, but it is not uncommon for schedule and cost stress to result in less testing than initially planned. Therefore, integrated testing, or "testing as you fly," is essential as a final check on the design and assembly to catch any errors prior to the mission. This presentation will outline the unique benefits of integrated testing by catching critical flight errors that can otherwise go undetected, discuss HRA methods that are used to identify opportunities for human error, lessons learned and challenges over ownership of testing will be discussed.

Young, Aaron↗
NASA NTRS2017

Pisgah Lava Cave Communication Test: Science Case Study for the Networked Constellations Initiative

As part of the science case study for the Networked Constellations initiative, a team of JPL scientists explore the possibility of a mission to study the lava caves on Mars. Natural caves on Mars and the Moon present a unique opportunity to learn about the planetary geology and to provide a shelter for human explorers. Due to power and communication challenges, a network of assets has significant advantages over a single asset sent inside a cave. However, communication between the assets and the data downlink present significant difficulties due to the presence of rough walls, boulders, and other obstacles with unknown dielectric constant inside a typical cave, disturbing the propagation of the radio waves. A detailed study is needed to establish the limitations of the current communication technologies and to develop requirements for the new communication technology applicable to the cave environment. On May 4 of 2017, Konstantin Belov, Doug Ellison, and Abby Fraeman visited a lava cave in Pisgah, CA. The purpose of the visit was to build a 3D map of the cave, which could be used to create a model of radio wave propagation, and to conduct a series of communication tests using off-the-shelf equipment to verify the in-cave communication challenges. This experiment should be considered as a simple 'proof of concept' and is the subject of this report.

Belov, K.↗
NASA NTRS2017

Using Information from Rendezvous Missions For Best-Case Appraisals of Impact Damage to Planet Earth Caused By Natural Objects

The Asteroid Threat Assessment Project (ATAP), a part of NASAs Planetary Defense Coordination Office (PDCO) has the responsibility to appraise the range of surface damage by potential asteroid impacts on land or water. If a threat is realized, the project will provide appraisals to officials empowered to make decisions on potential mitigation actions. This paper describes a scenario for assessment of surface damage when characterization of an asteroid had been accomplished by a rendezvous mission that would be conducted by the international planetary defense community. It is shown that the combination of data from ground and in-situ measurements on an asteroid provides knowledge that can be used to pin-point its impact location and predict the level of devastation it would cause. The hypothetical asteroid 2017 PDC with a size of 160 to 290 m in diameter to be discussed at the PDC 2017 meeting is used as an example. In order of importance for appraising potential damage, information required is: (1) where will the surface impact occur? (2) What is the mass, shape and size of the asteroid and what is its entry state (speed and entry angle) at the 100 km atmospheric pierce point? And (3) is the asteroid a monolith or a rubble pile? If it is a rubble pile, what is its sub and interior structure? Item (1) is of first order importance to determine levels of devastation (loss of life and infrastructure damage) because it varies strongly on the impact location. Items (2) and (3) are used as input for ATAPs simulations to define the level of surface hazards: winds, overpressure, thermal exposure; all created by the deposition of energy during the objects atmospheric flight, and/or cratering. Topics presented in this paper include: (i) The devastation predicted by 2017 PDCs impact based on initial observations using ATAPs risk assessment capability, (ii) How information corresponding to items (1) to (3) could be obtained from a rendezvous mission, and (iii) How information from a rendezvous mission could be used, along with that from ground observations and data from the literature, could provide input for an new risk analysis capability that is emerging from ATAPs research. It is concluded that this approach would result in appraisal with the least uncertainty possible (herein called the best-case) using simulation capabilities that are currently available or will be in the future.

Arnold, James O.↗
NASA NTRS2017

Using Information from Rendezvous Missions For Best-Case Appraisals of Impact Damage to Planet Earth Caused By Natural Objects

The Asteroid Threat Assessment Project (ATAP), a part of NASAs Planetary Defense Coordination Office (PDCO) has the responsibility to appraise the range of surface damage by potential asteroid impacts on land or water. If a threat is realized, the project will provide appraisals to officials empowered to make decisions on potential mitigation actions. This paper describes a scenario for assessment of surface damage when characterization of an asteroid had been accomplished by a rendezvous mission that would be conducted by the international planetary defense community. It is shown that the combination of data from ground and in-situ measurements on an asteroid provides knowledge that can be used to pin-point its impact location and predict the level of devastation it would cause. The hypothetical asteroid 2017 PDC with a size of 160 to 290 m in diameter to be discussed at the PDC 2017 meeting is used as an example. In order of importance for appraising potential damage, information required is: (1) where will the surface impact occur? (2) What is the mass, shape and size of the asteroid and what is its entry state (speed and entry angle) at the 100 km atmospheric pierce point? And (3) is the asteroid a monolith or a rubble pile? If it is a rubble pile, what is its sub and interior structure? Item (1) is of first order importance to determine levels of devastation (loss of life and infrastructure damage) because it varies strongly on the impact location. Items (2) and (3) are used as input for ATAPs simulations to define the level of surface hazards: winds, overpressure, thermal exposure; all created by the deposition of energy during the objects atmospheric flight, andor cratering. Topics presented in this paper include: (i) The devastation predicted by 2017 PDCs impact based on initial observations using ATAPs risk assessment capability, (ii) How information corresponding to items (1) to (3) could be obtained from a rendezvous mission, and (iii) How information from a rendezvous mission could be used, along with that from ground observations and data from the literature, could provide input for an new risk analysis capability that is emerging from ATAPs research. It is concluded that this approach would result in appraisal with the least uncertainty possible (herein called the best-case) using simulation capabilities that are currently available or will be in the future.

Arnold, J. O.↗
NASA NTRS2017

Using Information from Rendezvous Missions for Best-Case Appraisals of Impact Damage to Planet Earth Caused by Natural Objects

The Asteroid Threat Assessment Project (ATAP), a part of NASAs Planetary Defense Coordination Office (PDCO) has the responsibility to appraise the range of surface damage by potential asteroid impacts on land or water. If a threat is realized, the project will provide appraisals to officials empowered to make decisions about potential mitigation actions. This paper describes a scenario for assessment of surface damage when characterization of an asteroid had been accomplished by a rendezvous mission that would be conducted by the international planetary defense community. It is shown that the combination of data from ground and in-situ measurements on an asteroid provides knowledge that can be used to pin-point its impact location and predict the level of devastation it would cause. The hypothetical asteroid 2017 PDC with a size range of 160 to 290 m in diameter to be discussed at the PDC 2017 is used as an example. In order of importance for appraising potential damage, information required is: (1) where will the surface impact occur? (2) what is the mass, shape and size of the asteroid and what is its entry state (speed and entry angle) at the 100 km atmospheric pierce point? And (3) is the asteroid a monolith or a rubble pile? If it is a rubble pile, what is its structure and heterogeneity from the surface and throughout its interior? Item (1) is of first order importance to determine levels of devastation (loss of life and infrastructure damage) because it varies strongly on the impact location. Items (2) and (3) are used as inputs for ATAPs simulations to define the level of surface hazards: winds, overpressure, thermal exposure; all created by the deposition of energy during the objects atmospheric flight, andor cratering. Topics presented in this paper include: (i) the devastation predicted by 2017 PDCs impact on land based on initial observations using ATAPs risk assessment capability, (ii) how information corresponding to items (1) to (3) could be obtained from a rendezvous mission, and (iii) how information from a rendezvous mission could be used, along with that from ground observations and data from the literature to provide input for a new risk analysis capability that is emerging from ATAPs research. It is concluded that this approach would result in the creation of an appraisal of the threat from 2017 PDC with the least uncertainty possible, herein called the best-case.

Asteroid Impact Appraisals↗
NASA NTRS2018

Government Quality Management Systems: Case Study from the Hawaii Missile Alert

The unfortunate Hawaii False Ballistic Missile Alert event on January 13, 2018 provides many examples of how a Quality Management System (QMS, e.g. ISO 9001 Quality Management Systems-Requirements) can be applied to government operations, and illustrates the need for existing quality standards to provide more clarity in their applicability to services. The event provides a valuable case study for those who ask the question: how do QMS systems and standards apply to government services? The following information is taken from the Hawaii Emergency Management Agency (EMA) investigation report.

Shepherd, Christena C.↗
NASA NTRS2018

Generalizing a Data Analysis Pipeline in the Cloud to Handle Diverse Use Cases in NASA's EOSDIS

NASA's Earth Observing System Data and Information System (EOSDIS) is tasked with archiving and distributing Earth Observation data across a range of disciplines, including atmospheric science, oceanography, land processes, natural hazards, solar radiance and even socioeconomic aspects relating to the environment. Driven by rapidly rising data volumes, EOSDIS is migrating to a cloud computing based archive over the next few years. Although this simplifies data management somewhat, the main aim is to provide the data in an environment where end users can bring their analysis to the data rather than attempting to download and manage ever-increasing volumes. To that end, a cloud-based analysis platform is being constructed to enable data transformations, analyses and visualization without egressing the data from the cloud. In this endeavor, we expect a wide variety of users, algorithms and use cases. Consequently, the architecture of this cloud analytics platform is expressly designed to be based on open services, thus fostering an ecosystem that enables the efficient combination of common components with data-specific or analysis-specific components. Reviewed and approved by Andrew Mitchell, ESDIS project manager.

Cloud computing↗
NASA NTRS2018

A Case for Bundle Protocol in Space

NASA, through the Advanced Exploration Systems (AES) project, is investing in the development and infusion of delay tolerant networking (DTN) protocols for use on future space flight missions. The cornerstone of the DTN suite is the Bundle Protocol which provides network layer addressing and routing of data blocks. In 2017, the Plankton, Aerosol, Cloud, and Ocean Ecosystem (PACE) mission was selected as the first in-house robotic science mission to implement the Bundle Protocol for downlink of housekeeping telemetry. One year into the design and incorporation of the Bundle Protocol on PACE, this presentation makes a case for using the Bundle Protocol for communication with future space assets. Specifically, the use of the Bundle Protocol (1) simplifies relaying data through store and forward routing and custody transfer; (2) simplifies downlink management through delivery guarantees; and (3) simplifies storage services through block level interactions with memory devices.

Swinski, J. P.↗
NASA NTRS2019

The First NuSTAR Observation of 4U 1538-522: Updated Orbital Ephemeris and a Strengthened Case for an Evolving Cyclotron Line Energy

We have performed a comprehensive spectral and timing analysis of the first NuSTAR observation of the high-mass X-ray binary 4U 1538−522. The observation covers the X-ray eclipse of the source, plus the eclipse ingress and egress. We use the new measurement of the mid-eclipse time to update the orbital parameters of the system and find marginally significant evolution in the orbital period, with P(sub orb) / P(sub orb) = (-0.95 +/- 0.37) x 10(exp -6) yr(exp -1). The cyclotron line energy is found to be approximately 1.2 keV higher than RXTE measurements from 1997 to 2003, in line with the increased energy observed by Suzaku in 2012 and strengthening the case for secular evolution of 4U 1538−522's CRSF. We additionally characterize the behavior of the iron fluorescence and emission lines and line-of-sight absorption as the source moves into and out of eclipse.

Hemphill, Paul B.↗
NASA NTRS2019

Effect of Grazing Flow on Grooved Over-the-Rotor Acoustic Casing Treatments

After testing grooved over-the-rotor acoustic casing treatments on a turbofan rotor, a follow-on study was performed to investigate the effect of flow on grooved acoustic liners. The experiment was performed to understand the scaling of acoustic liner absorption with grazing flow and investigate a potential noise source from grooved acoustic liners. Acoustic liner absorption and reflection characteristics were quantified by examining the reduction in amplitude of a plane wave traveling over 2 inch liners with grazing flow. For all liners tested, as the grazing flow Mach number is increased, the absorption curves broadened and the frequency of peak absorption decreased. Grazing flow over a series of grooves was found to generate resonances up to 152 dB sound pressure level. Adding acoustic treatment to the bottom of these grooves was found to reduce the magnitude of this resonance by up to 10 dB sound pressure level and increase its frequency by up to 10%. The quantification of the grazing flow effect and identification of a mechanism behind the noise penalty from the prior turbofan rotor experiment will aid in the design of future over-the-rotor treatments.

acoustic↗
NASA NTRS2019

NAI Supported Research, a Case Study: the Origin of Protein Functions

In the 20 years of its existence, the NAI supported a host of studies that fundamentally advanced the field of astrobiology in terms of both understanding the underlying concepts and developing novel research techniques. In this presentation, I will recount one such case in the field of the origin of life, whereby application of new, powerful experimental techniques combined with state-of-the art computer simulations led to a surprising insight into the origin of protein functions.

Pohorille, Andrew↗
NASA NTRS2019

Rest-Frame UV and Optical Emission Line Diagnostics of Ionized Gas Properties: a Test Case in a Star-Forming Knot of a Lensed Galaxy at Z ∼ 1.7

We examine the diagnostic power of rest-frame ultraviolet (UV) nebular emission lines, and compare them to more commonly used rest-frame optical emission lines, using the test case of a single star-forming knot of the bright lensed galaxy RCSGA 032727–132609 at redshift z ∼ 1.7. This galaxy has complete coverage of all the major rest-frame UV and optical emission lines from Magellan/MagE and Keck/NIRSPEC. Using the full suite of diagnostic lines, we infer the physical properties: nebular electron temperature (T(sub e)), electron density (n(sub e)), oxygen abundance (log (O/H), ionization parameter [log (q), and interstellar medium (ISM) pressure (log (P/k)]. We examine the effectiveness of the different UV, optical, and joint UV–optical spectra in constraining the physical conditions. Using UV lines alone we can reliably estimate log (q), but the same is difficult for log (O/H). UV lines yield a higher (∼1.5 dex) log (P/k) than the optical lines, as the former probes a further inner nebular region than the latter. For this comparison, we extend the existing Bayesian inference code IZI, adding to it the capability to infer ISM pressure simultaneously with metallicity and ionization parameter. This work anticipates future rest-frame UV spectral data sets from the James Webb Space Telescope (JWST) at high redshift and from the Extremely Large Telescope (ELT) at moderate redshift.

Acharyya, Ayan↗
NASA NTRS2020

Application of Machine Learning Techniques to Aviation Operations: NASA Case Studies

There is an increasing interest in applying methods based on Machine Learning Techniques(MLT) to problems in aviation operations. The current interest is based on developments in Cloud Computing, the availability of open software and the success of MLT in automation, consumer behavior and finance involving large database. Historically aviation operations have been analyzed using physics-based models and provide information for making operational decisions. This talk describes issues to be addressed in applying either model-driven or data-driven methods. Aviation operations involving many decision makers, multiple objectives, poor or unavailable physics-based models and a rich historical database are prime candidates for analysis using data-driven methods. The issues relating to data, feature selection and validation of the models are illustrated by examining case studies of the application of MLT to problems in air traffic management at NASA. Further research is needed in the application of MLT to critical aviation operations. As always, the best approach depends on the task, the physical understanding of the problem and the quality and quantity of the available data.

Sridhar, Banavar↗
NASA NTRS2020

How Satellite Soil Moisture Data Can Help to Monitor the Impacts of Climate Change: SMAP Case Studies

Socially and economically costly extreme weather events have become more prevalent in the last decade. Monitoring and early warning systems could help mitigate the impact of such events by allowing people to better prepare themselves to manage their responses to these events. One significant element of an effective warning system is soil moisture because it is a key determinant of the exchange of water and heat energy between the land and atmosphere, the partitioning of precipitation between infiltration and runoff, and therefore has an influence on weather patterns and streamflow. In addition, soil moisture governs plant water availability – the key to crop yield forecasting. For these reasons, a wide range of organizations use soil moisture information to better predict and monitor climate and weather phenomena such as floods and droughts. By improving soil moisture estimates, it may be possible to improve the monitoring and early warning systems upon which these organizations rely, and hence better mitigate the impacts of extreme weather events. Through case studies, this article discusses several uses of soil moisture data products from NASA’s Soil Moisture Active Passive (SMAP) mission to help improve soil moisture-related monitoring and early warning systems.

Drought monitoring↗
NASA NTRS2019

FUN3D and USM3D Analysis of the Propulsion Aerodynamic Workshop 2018 S-Duct Test Case

This work presents the results of Fun3D and USM3D analyses that were performed for the 4th AIAA Propulsion Aerodynamics Workshop (PAW). The PAW workshop is separated into three sections that focus on internal duct flows, nozzle flows and a special topic. This paper focuses on the internal duct flow section of PAW04 while an accompanying paper discusses the analyses performed for the nozzle portion. For the internal duct flow section, the PAW04 participants were provided with the two configurations consisting of an S-duct with and without aerodynamic interface plane (AIP) rake legs modeled. The participants were asked to perform a grid refinement study as well as a turbulence model study for the configuration with the rake legs. The analyses discussed here were performed on custom grids developed under the guidelines of the workshop. Additionally, the paper discusses the development and use of flow controllers for matching the desired flow characteristics. The results show that both solvers do well for predicting internal flow characteristics of the S-duct based on direct comparison with the experimental data. However, the CFD-to-CFD comparison proved to be more challenging due to the localized occurrence of supersonic flow near the rake legs when using the mass flow controller. A turbulence model study was performed to compare the two-equation SST model to the SA-QCR model. The results show that although the turbulence model does affect the solution, it makes a minimal impact on pressure recovery and inlet distortion intensity for this case. Suggestions for future workshops include gridding guidelines similar to those employed for the Drag Prediction Workshop series for the grid refinement study and a time accuracy study.

Carter, Melissa B.↗
NASA NTRS2019

FUN3D and USM3D Analysis of the 4th AIAA Propulsion Aerodynamics Workshop Nozzle Test Case

This work presents the results of FUN3D and USM3D analyses that were performed for the 4th AIAA Propulsion Aerodynamics Workshop. The workshop was separated into three sections that focus on internal duct flows, nozzle flows, and a special topic of interest. This paper focuses on the nozzle section while an accompanying paper discusses the analyses performed for the internal duct flow section. For the nozzle flow section, the participants were provided with two configurations consisting of a rectangular convergent nozzle with and without an aft-deck. User-generated grids were developed under the guidelines of the workshop for the present analyses. The results show that both solvers compare favorably to the experimental results for the baseline nozzle with the largest differences observed at the lower NPR values. Additionally, both solvers showed favorable agreement with the experimental data for the pressures on the surface of the aft-deck. However, neither solver was able to match the jet flow further downstream for the nozzle with aft-deck configuration. A turbulence model study was conducted to compare the two-equation SST model, SA-QCR model, and two-equation k-kL model (FUN3D only). The results show that the SA-QCR turbulence model was unable to match the experimental results downstream of the nozzle. The k-kL model was shown to better match the experimental data compared to the SST model for most cases simulated using the FUN3D flow solver. Suggestions for future workshops include gridding guidelines similar ion Workshop series for the grid refinement study and a reduction in scope to allow for more detailed exploration of the individual problems. rticipation by reducing time requirements

Bozeman, Michael D.↗
NASA NTRS2020

Sketch-to-Solution: A Case Study in RCS Aerodynamic Interaction

Thanks to recent advances in the fields of anisotropic grid adaptation, error estimation, and geometry modeling, a sketch-to-solution work flow is now possible for viscous computational fluid dynamic (CFD) simulations. With this workflow, a CFD application engineer provides geometry, boundary conditions, and flow parameters; and the sketch-to-solution process yields a CFD simulation through automatic, error-based, grid adaptation. To explore the benefits of this nascent capability, a conventional manual grid generation work flow is compared to this new automatic grid generation work flow for a given engineering question: What are the aerodynamic interactions caused by the reaction control system (RCS) on an entry vehicle? This case study indicates that while the automatic grid generation sketch-to- solution process is not yet mature, it is preferred over a manual grid generation work flow because it greatly reduces manual labor, eliminates many opportunities for human error, and provides grid sensitivity information.

Bill Kleb↗

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