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At least 415 records · Page 23

2nd Workshop of Human-Automation Interaction Considerations for UAS Integration

NASA's Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project (UAS-NAS) and the UAS Executive Committee (EXCOM) Science and Research Panel (SARP) invite you to attend the 2nd Workshop on Human-Automation Interaction Considerations for UAS Integration. A follow on to the workshop hosted by the National Academies of Science, Engineering and Medicine, this two-day workshop aims to tackle two critical issues for UAS integration in the NAS being addressed by NASA and the SARP: control of multiple UAS by a single, or multiple, operators (multi-UAS), and automatic collision avoidance (auto-CA). Attendees will be asked to generate real human-automation architecture and human machine interface solutions for these problems during interactive breakout sessions. Attendance is limited to select government and academia invitees only. This presentation is outlines the objectives of the workshop.

human-automation interaction↗

Architectural and Operational Considerations Emerging from Hybrid RF-Optical Network Loading Simulations

A technology demonstration of free space optical communication at interplanetary distances is planned via one or more future NASA deep-space missions. Such demonstrations will “pave the way” for operational use of optical communications on future robotic/potential Human missions. Hence, the Deep Space Network architecture will need to evolve. Preliminary attempts to model the anticipated future mission set and simulate how well it loads onto assumed architectures with combinations of RF and optical apertures have been evaluated. This paper discusses the results of preliminary loading simulations for hybrid RF-optical network architectures and highlights key mission and ground infrastructure considerations that emerge.

loading simulations↗

Capability Considerations for Enhancing Safety on Long Duration Crewed Missions: Insights from a Technical Interchange Meeting on Autonomous Crew Operations

As future flight crews on long duration deep space missions are expected to operate more autonomously, considerations must be given to onboard capabilities and human-computer teaming that will fortify the safety net traditionally provided by the Mission Control Center. In August 2018, the Human Factors and Behavioral Performance Element of NASA's Human Research Program convened a Technical Interchange Meeting (TIM) on Autonomous Crew Operations at NASA Ames Research Center to address how intelligent technologies can be utilized to augment crew capabilities to support real-time anomaly response. In this paper, we highlight three topic areas discussed at the TIM that have direct implications for future crew anomaly response capabilities: smart structures, cognitive assistants, and manpower.

autonomous crew operations↗

Thermal, Avionics, and Power Considerations for Designing a Nuclear Thermal Propulsion Flight Demonstrator

As part of the Appropriations Bill passed by the US Congress in February 2019, NASA was instructed to develop a nuclear thermal propulsion (NTP) flight demonstrator by 2024. [4] In response to this directive, the Advanced Concepts Office (ACO) at Marshall Space Flight Center (MSFC) was tasked with beginning concept studies for the flight demonstration (FD) mission. During the NTP study formulation, two philoso- phies emerged with regards to FD concept design. The first, Flight Demo 1 (FD1), strictly observes the 2024 schedule requirement at the expense of lower engine performance than expected of theoretical NTP engines. The second concept, Flight Demo 2 (FD2), relaxes the schedule requirement to allow for higher engine performance and more traceability to future operational systems. Both the FD1 and FD2 concepts present considerable challenges for subsystem design, specifically in the areas of thermal control, avionics, and power. To guard against undesired graveyard orbits, a requirement to keep the NTP engine and the reaction control system (RCS) separate was put in place. As a result of this requirement, the avionics subsystem must provide separate command and data handling (CDH) and instrumentation for each propulsion system. In-space instrumentation and monitoring of a NTP system has never been done before, necessitating the development of novel strategies and unique hardware. The heating rates produced by the NTP engine are extremely high, leading to difficulties with thermal control. The FD1 concept utilizes high-pressure gaseous hydrogen (GH2), which is largely insensitive to temperature fluctuations. The FD2 concept, however, utilizes cryogenic liquid hydrogen (LH2) which must be kept stable near 20 Kelvin. A high-performance thermal control system (TCS) will be required to ensure all components and subsystems are maintained within their operational temperature ranges. This paper will highlight the thermal, avionics, and power solutions required for the full scope of challenges for a NTP flight demonstrator.

Johnson, W. E.↗

Restricted and Uncontained: Health Care and Public Health Considerations in the Event of Loss of Containment During the Restricted Earth Return of Extraterrestrial Samples

The normal scope of an adequate public health response to released biological material is framed by working with biological vectors with known pathogenicity and virulence. Defining the scope of a response to the release of biological material with unknown pathogenicity and virulence enters into a novel and yet to be framed domain. A current case, the case of returning samples from a location other than Earth, extraterrestrial samples from a location such as Mars, which may harbor life as we know it, requires framing a public health response. An unintentional release of biological material with unknown pathogenicity and virulence may occur when biological containment mechanisms in the Earth-returning transport method are lost. This paper raises initial public health and healthcare response questions during a return of extraterrestrial samples to Earth, in the event of its release from biological containment mechanisms: How does the public health community prepare for a response when there is release of samples that may contain potential extraterrestrial organisms from a planetary body or hardy terrestrial organisms surviving a round trip? If a mishap occurs during the return of these samples, what considerations need to be made to confine, decontaminate, and collect material in regions around the mishap? How will the public health community work with relevant government organizations to prepare the general public? The unknowns of exposure, potential extraterrestrial pathogenicity, and decontamination approaches, underscore gaps in biopreparedness for this novel case from the federal to local levels.

Betsy Pugel↗

Terminal Area Considerations for UAS Detect and Avoid

Unmanned Aircraft Systems need to be able to comply with manned aviation ‘see and avoid’ separation requirements. A Detect and Avoid (DAA) System includes sensors, a tracker, and alerting and guidance algorithms that assist a remote pilot in maintaining separation from airborne traffic. To date, DAA system requirements development has focused on operations transiting to and from Class A or special use airspace. Current efforts are defining DAA system requirements for operations in and around terminal airspace. As a contribution to the current efforts, this paper highlights results from a Human in the Loop (HiTL) experiment comparing methods of changing from the transit-specific alerting and guidance criteria to proposed terminal-specific alerting and guidance criteria. It discusses operational considerations that are beyond the HiTL.

Unmanned Aircraft Systems↗

Surviving and Thriving in Space and on Earth's Oceans - Human Logistics and Sustainability Comparisons and Considerations

The human species has a yearning for exploration as evidenced by the extensive historical ocean voyages and expeditions which have led to a massive advancement in the scientific and geodetic knowledge about planet Earth. These global explorations via the oceans have also had strategic, economic, cultural and religious implications and impacts, which have drastically changed the state of humanity and its condition. The transportation network created by ships traveling across the oceans has been supplemented by other transportation networks on land and in the air, creating a global economy that, in general, has improved the human condition leading to better health, longer lives, lower child mortality, better education, political freedom, higher gross national product (GNP) and improved hygiene. The logical extension of this societal trend is to extend the transportation network and human civilization into outer space, beyond the cradle of planet Earth. Our solar system contains vast amounts of natural resources which can be harnessed and used to bootstrap a space economy and related infrastructure by using advanced technologies. Sailing journeys from hundreds of years ago required large vessels and large crews, (in comparison with today’s space capsules). Modern sailors of today are able to complete large voyages, in small vessels, with a minimal crew, comparable in magnitude to modern space travel. This paper will use a systems engineering approach (e.g. using the NASA Human Integration Design Handbook (HIDH), NASA-SP-2010-3407, 2010 and the “Advanced Life Support Baseline Values and Assumptions Document, (BVAD)” NASA-CR-2004-208941, 2004.), to examine and compare the logistics and sustainability aspects of a small crew traveling on Earth's oceans in sailing vessels versus humans traveling in space. The “Mālama Honua Worldwide Voyage” of the Hokule’a, a replica of an ancient Hawaiian double hulled sailing canoe, will be used as a case study. This is the best comparison case since the Polynesian exploration of the vast (and virtually empty) Pacific Ocean is the closest analogue to modern space travel. “"Both are voyages of exploration.” –Shuttle astronaut Lacy Veach. Minimizing waste and maximizing re-use and re-cycling will lead to more efficient logistics and sustainability. In addition, In-Situ Resource Utilization (ISRU) strategies, based on successful Earth based strategies used for many years by sailors will be considered and evaluated for their usefulness. For example, human logistics for a typical space mission are shown in Table 1 and Table 2 (Lopez et al, 2015). Studies show that typical human water consumption in space is projected to be 3.2 kg/day per crew member as shown in Table 2. Data from human sailing voyages around the globe will be examined. Anecdotal evidence indicates that knowledgeable and well-equipped modern sailors, who conserve water, can comfortably live using 1.5 to 5 kg/day per person. This paper will investigate key logistics and sustainability aspects of living in space and compare them quantitatively to similar aspects of living on ocean faring sailing vessels on Earth. Mutually beneficial observations, advanced technologies and modern considerations will be applied within confines of a remote sailing environment, which could be of immense value to both the space faring community and the ocean sailing community.

Space↗

Effective Crewed Surface Science near the Lunar South Pole: Some Illumination Considerations

Exploration near the lunar South Pole has substantial scientific promise for expanding our understanding of the Moon beyond what has been accomplished by Apollo and other lunar missions. An obvious difference from the Apollo experience is that the polar location for Artemis will guarantee the Sun is going to be low above the horizon. A great deal of excellent work has been, and is being, done on the availability of light (“yes/no”) for exploration purposes [e.g., 1-4]. However, we raise the additional consideration of the qualitative effects of low solar elevation on crew traverses, crew observations, and other science measurements [see also 5, though ground rules of that study presumed higher Sun]. We emphasize that our view is that these issues are unlikely to be mission objective-threatening, particularly if adequately considered in advance.

C. I. Fassett↗

Display and Automation Considerations for the Airborne Collision Avoidance System Xu

In this paper we examine several display and automation considerations of a collision avoidance system that is currently under development: the Airborne Collision Avoidance System (ACAS) Xu. This study builds on previous work conducted as part of NASA’s Unmanned Aircraft Systems (UAS) Integration into the National Airspace System (NAS) project. ACAS Xu represents the next-generation successor to the Traffic Alert and Collision Avoidance System (TCAS II), wherein the Xu variant is intended for UAS applications. Whereas TCAS II exclusively issues RAs in the vertical dimension, a major distinction between ACAS Xu and previous collision avoidance (CA) systems is the introduction of horizontal and “blended” RAs (i.e., RAs with both horizontal and vertical components). This present work was conducted as an engineering analysis involving two parts. In Part 1, a two-by-two, within-subjects study was performed that manipulated how RAs were presented to a pilot situated at a UAS ground control station. Five participants experienced four experimental trials in which text and aural alerting characteristics were manipulated. In Part 2, another five participants experienced four trials in which the levels of automation were manipulated with regard to the CA and return-to-course (RTC) tasks. The results for Part 1 found no effect of display or alerting configuration on pilot performance. However, it was discovered that pilot response time to RAs greatly depended on the RA type. In particular, pilots were quicker to respond to vertical RAs (M = 4.52 seconds) than horizontal (M = 7.42 seconds) and blended (M = 9.68 seconds) RAs in which both dimensions were issued simultaneously. For Part 2 of the study, pilots found both auto-CA and auto-RTC functions equally useful. Most pilots were comfortable with the automation, however responses were mixed. Three of five participants indicated high levels of comfort with the auto-CA function, while two rated their comfort as low. Pilots’ comfort for the auto-RTC functionality was slightly higher: four out of five pilots gave high ratings, while one pilot gave a low rating. Overall, pilots ordinally ranked their preference for automated functions as auto-CA together with auto-RTC (when an aural alert announces a change between CA and RTC states), auto-CA, and auto-CA and RTC (without the aural state-change announcement). Recommendations for improving the display of automation are also discussed.

collision avoidance↗

Display and Automation Considerations for the Airborne Collision Avoidance System Xu

In this presentation we examine several display and automation considerations of a collision avoidance system that is currently under development: the Airborne Collision Avoidance System (ACAS) Xu. This study builds on previous work conducted as part of NASA’s Unmanned Aircraft Systems (UAS) Integration into the National Airspace System (NAS) project. ACAS Xu represents the next-generation successor to the Traffic Alert and Collision Avoidance System (TCAS II), wherein the Xu variant is intended for UAS applications. Whereas TCAS II exclusively issues RAs in the vertical dimension, a major distinction between ACAS Xu and previous collision avoidance (CA) systems is the introduction of horizontal and “blended” RAs (i.e., RAs with both horizontal and vertical components). This present work was conducted as an engineering analysis involving two parts. In Part 1, a two-by-two, within-subjects study was performed that manipulated how RAs were presented to a pilot situated at a UAS ground control station. Five participants experienced four experimental trials in which text and aural alerting characteristics were manipulated. In Part 2, another five participants experienced four trials in which the levels of automation were manipulated with regard to the CA and return-to-course (RTC) tasks. The results for Part 1 found no effect of display or alerting configuration on pilot performance. However, it was discovered that pilot response time to RAs greatly depended on the RA type. In particular, pilots were quicker to respond to vertical RAs (M = 4.52 seconds) than horizontal (M = 7.42 seconds) and blended (M = 9.68 seconds) RAs in which both dimensions were issued simultaneously. For Part 2 of the study, pilots found both auto-CA and auto-RTC functions equally useful. Most pilots were comfortable with the automation, however responses were mixed. Three of five participants indicated high levels of comfort with the auto-CA function, while two rated their comfort as low. Pilots’ comfort for the auto-RTC functionality was slightly higher: four out of five pilots gave high ratings, while one pilot gave a low rating. Overall, pilots ordinally ranked their preference for automated functions as auto-CA together with auto-RTC (when an aural alert announces a change between CA and RTC states), auto-CA, and auto-CA and RTC (without the aural state-change announcement). Recommendations for improving the display of automation are also discussed.

collision avoidance↗

Operational Considerations for Fission Reactors Utilized on Lunar In-Situ Resource Utilization Missions: A Report to the Nuclear Power & Propulsion Technical Discipline Team

This report identifies the considerations related to the operation of space nuclear power reactors that would be utilized for In Situ Resource Utilization (ISRU) missions on the lunar surface. The objective of this study is to evaluate the operational complexities of reactors that would provide electrical and thermal power to a growing lunar ISRU and mining outpost/base.

Fission reactor↗

Operational Considerations for Fission Reactors Utilized on Nuclear Thermal Propulsion Missions to Mars

This report is aimed at identifying the implications associated with the operation of space nuclear power reactors that would be utilized for Nuclear Thermal Propulsion (NTP) missions to Mars. The objective of this study is to evaluate the operational features of reactors that could provide propulsion and possibly electrical power for future crewed and cargo missions to Mars. This report follows upon an initial report looking at the generic considerations for operating fission reactors in space applications and is intended as a deeper dive into the operational features related to specific Mars NTP applications.

Nuclear Thermal Propulsion↗

Relay Satellite Orbit Selection Considerations for Future Robotics Missions to Explore Venus

Discusses orbit design trades relevant to use of a Venus orbiting relay satellite supporting a variety of potential Venus robotic mission types. The emphasis is on the impact of mission tele- communications requirements on selection of a relay satellite orbit and its characteristics that can benefit or hinder mission performance for the potential robotic missions now under consideration.

Venus↗

Considerations for the Extension of Gas Path Analysis to Electrified Aircraft Propulsion Systems

Aircraft operators rely on gas path analysis techniques for monitoring the performance and health of their gas turbine engine assets. This is accomplished by analyzing discernable shifts in measurement parameters acquired from the engine. This paper reviews the founding mathematical principles of gas path analysis, including conventional approaches applied for estimating engine performance deterioration. Considerations for extending the application of gas path analysis techniques to Electrified Aircraft Propulsion (EAP) systems is also discussed, and simulated results from their application to an EAP concept comprised of turbomachinery and electrical system hardware is provided. Results are provided comparing the parameter estimation accuracy offered by taking a whole-system approach towards the problem setup versus that offered by analyzing each subsystem individually. For the latter, the importance of having accurate direct or inferred measurements of external mechanical torque loads placed upon turbomachinery shafts is emphasized.

Electrified Aircraft Propulsion↗

Considerations for the Extension of Gas Path Analysis to Electrified Aircraft Propulsion Systems

Aircraft operators rely on gas path analysis techniques for monitoring the performance and health of their gas turbine engine assets. This is accomplished by analyzing discernable shifts in measurement parameters acquired from the engine. This paper reviews the founding mathematical principles of gas path analysis, including conventional approaches applied for estimating engine performance deterioration. Considerations for extending the application of gas path analysis techniques to Electrified Aircraft Propulsion (EAP) systems is also discussed, and simulated results from their application to an EAP concept comprised of turbomachinery and electrical system hardware is provided. Results are provided comparing the parameter estimation accuracy offered by taking a whole-system approach towards the problem setup versus that offered by analyzing each subsystem individually. For the latter, the importance of having accurate direct or inferred measurements of external mechanical torque loads placed upon turbomachinery shafts is emphasized.

Electrified Aircraft Propulsion↗

Considerations for the Extension of Gas Path Analysis to Electrified Aircraft Propulsion Systems

Aircraft operators rely on gas path analysis techniques for monitoring the performance and health of their gas turbine engine assets. This is accomplished by analyzing discernable shifts in measurement parameters acquired from the engine. This paper reviews the founding mathematical principles of gas path analysis, including conventional approaches applied for estimating engine performance deterioration. Considerations for extending the application of gas path analysis techniques to Electrified Aircraft Propulsion (EAP) systems is also discussed, and simulated results from their application to an EAP concept comprised of turbomachinery and electrical system hardware is provided. Results are provided comparing the parameter estimation accuracy offered by taking a whole-system approach towards the problem setup versus that offered by analyzing each subsystem individually. For the latter, the importance of having accurate direct or inferred measurements of external mechanical torque loads placed upon turbomachinery shafts is emphasized.

Electrified Aircraft Propulsion↗

Human Factors Considerations for Pressurized Crew Transfer Between Ascent or Lander Spacecraft and Surface Assets

An option for pressurized crew transfer between surface assets and lander or ascent spacecraft offers multiple advantages. The most important are the loss of life risks due to crew member injuries or surface spacesuit failures. However, even in nominal scenarios pressurized crew transfer is advantageous, protecting lander and ascent spacecraft as well as launch and entry spacesuits from dust exposure and aiding in adaptation to gravity following prolonged periods of microgravity. Several examples of lunar and Mars lander or ascent spacecraft have been released publicly and can serve as examples of the range of potential vehicles that may benefit from pressurized crew transfer. There are also examples of surface assets that can be used to provide crew transfer, including both current surface mobility or crew transfer concepts and terrestrial examples that could be adapted to use on the Moon or Mars. In all cases, the resulting passageway must be acceptable for use and protected from itself experiencing dust contamination. Key design considerations will be discussed.

Artemis↗

Arm DevSummit Keynote: Environment for Data Engineering in Virtual Reality: Ethical Considerations

Currently, the US Government is going through a large-scale data Transformation effort, where the GSA playbook is guiding all agencies to make their processes data-driven with the help of emerging technologies. To address concerns about algorithm sharing, AI adoption, and vendor lock-in, the NASA Langley Research Center Digital Transformation Group has developed the Environment for Data Engineering in Virtual Reality (EnDEVR), a data science ecosystem that allows users to command and investigate customizable data analyses from a VR environment. The system has been evaluated in the Oculus Rift S and Quest environments, two popular VR systems powered by the ARM architecture. Current and future development will employ several AI capabilities to guide research and automation within the environment and to facilitate algorithm sharing. In this talk, we will discuss the results of an initial ethical investigation and recommended considerations for the use of AI within the system.

Artificial Intelligence↗