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At least 937 records · Page 52

Using a Crew Resource Management Framework to Develop Human-Autonomy Teaming Measures

Recent developments in technology have permitted an increased use of autonomy. To work best with humans, autonomy should have the qualities of a good team member. But how can these qualities be measured? One way is to use similar measures to those used to measure good teams with human members. For example, the Non-Technical Skills (NOTECHS) framework measures Crew Resource Management (CRM) skills that allow pilots to work together as a team. The framework consists of skill categories, elements of those categories, and behavioral markers that demonstrate good or poor performance in the elements. This paper introduces CMSD (CooperationManagementSituation AwarenessDecision Making), a measurement system based on NOTECHS and other widely-used skill level systems, which provides quantitative measures of Human-Autonomy Teaming (HAT).

Crew Resource Manaagement↗

Risk Reduction of Orion Multi-Purpose Crew Vehicle (MPCV) Program Government-Furnished Equipment for Environmental Control and Life Support (ECLS)

The NASA Engineering and Safety Center (NESC) was requested to conduct technical risk-reduction activities for safety-critical government-furnished environmental control and life support (ECLS) equipment for the Multi-Purpose Crew Vehicle Program. These items include the post-landing anomaly gas monitor, the in-flight anomaly gas monitor, the emergency breathing mask, the 144-hour in-suit survival capability, the portable fire extinguisher, the smoke eater, and the post-landing carbon dioxide control system. This document contains the outcome of the NESC assessment.

Environmental Control and Life Support↗

Protecting Crew and Surface Systems with a Long-Duration Lunar Safe Haven

NASA’s Artemis program will send astronauts to the lunar surface for extended mission durations throughout the 2030s, with a focus on sustainability and extensibility for Mars exploration, as described in NASA’s “Artemis Plan”. However, NASA must place more emphasis on protecting both the crew and the exploration surface systems if they hope to achieve long-duration sustainability on the lunar surface. It is now reasonably achievable with excavation, construction, and autonomy technologies to achieve a significant level of protection that architectures have been unable to achieve to date. The Lunar Safe Haven (LSH) was proposed to protect astronauts, electronics, and other surface exploration systems from the hazards of the lunar environment, including radiation, micrometeoroid strikes, lunar dust, thermal vacuum, etc. During the study, Level Zero Requirements were developed for the LSH, and a decision analysis framework was baselined to evaluate concepts. The LSH Study also performed a comprehensive trade study, during which it identified numerous alternatives for establishing and maintaining a safe haven shelter on the lunar surface. This paper reviews the products developed during the study and presents the final recommendations.

radiation shielding↗

Aerodynamic Loading on Crew Access Arm

An aerodynamic database for the crew access arm during deployment is generated. While initial attempts used data derived from wind tunnel testing, limitations lead to the use of computational fluid dynamics to improve analysis. This computational data compared favorably to the experimental data increasing confidence in both. Further analysis lead to simplification showing the ability to build the database with a single relative wind variable which takes into account both arm deployment angle and wind direction. Eventually geometric simplifications and conservative results lead to the use of simulations of the CAA alone to build the database.Finally these static conditions are then compared to a dynamic simulation where the CAA rotates into position to test the quasi-steady state assumptions used to generate the database. The dynamic case showed an increase in the moment of interest but within acceptable bounds for now.

SLS↗

Ground Wind Loads on the Space Launch System’s Mobile Launcher Crew Access Arm

An aerodynamic database for the crew access arm during deployment is generated. While initial attempts used data derived from wind tunnel testing, limitations lead to the use of computational fluid dynamics to improve analysis. This computational data compared favorably to the experimental data increasing confidence in both. Further analysis lead to simplification showing the ability to build the database with a single relative wind variable which takes into account both arm deployment angle and wind direction. Eventually geometric simplifications and conservative results lead to the use of simulations of the CAA alone to build the database.Finally these static conditions are then compared to a dynamic simulation where the CAA rotates into position to test the quasi-steady state assumptions used to generate the database. The dynamic case showed an increase in the moment of interest but within acceptable bounds for now.

SLS↗

Parametric Modeling of NTP Engine Performance for a Crewed Mars Mission

Nuclear thermal propulsion (NTP) has been studied extensively for use on a crewed mission to Mars, and NASA and DARPA are partnering in the development and demonstration of an NTP engine as part of the DRACO project. The specific impulse and thrust achieved by an engine in the context of a mission determines the propellant amount required to close the mission and the size of the vehicle required. An NTP engine has a slower start-up/shut-down transient than traditional chemical engines and requires post-firing cooling, and thus the average Isp for a burn is a function of the power ramp-up rate and the duration of the burn. An initial demonstration engine may target a lower Isp than the 900 sec that has been extensively studied by NASA. This paper shows the effect on the mission closure and vehicle sizing of the transient ramp rate performance and of lower than 900 sec specific impulse. Ammonia is considered as an alternate NTP propellant, with mission performance estimated.

NTP↗

NASA Exploration Toilet Hardware Status and Crew Feedback from ISS Artemis-2 Demonstration

The Universal Waste Management System (UWMS), ISS operational nomenclature “Toilet”, was initially installed on the International Space Station (ISS) in 2020 with final installation completed in 2021. Technical progress continues to be made with each on-orbit operation and will ultimately culminate with nominal US crew use of the hardware on ISS. During 2023, the Artemis-2 Demonstration was started, and this paper discusses issues encountered, on-orbit troubleshooting, subsequent ground failure investigation and proposed repairs as well as near-term plans to resume the Artemis-2 demo. Also discussed is an update to the commercial-off-the-shelf (COTS) Conductivity Monitor which is planned to be flown for the resumption of the demo along with additional UWMS hardware and Toilet Integration Hardware (TIH). An updated design of the commode seat and fecal bag for Artemis-2 UWMS will be demonstrated on ISS and a summary of the hardware is included in the paper. Use of the hardware during the first days of the aborted demonstration by crewmembers and feedback received is summarized as well as hardware updates resulting from that feedback. The paper will also provide an overview of the demo results to date that inform the Orion-installed UWMS unit and future manifesting of consumables for both Orion and ISS.

Toilet↗

Strategies for Quantifying Human Space Flight Performance in the Crew Health and Performance System

The Crew Health and Performance-Probabilistic Risk Assessment (CHP-PRA) team at NASA Glenn Research Center is planning a customized approach to quantify human spaceflight performance changes with respect to changes to the CHP system functions and capabilities. Using the Directed Acyclic Graphs (DAG) initiated by NASA’s Human Systems Risk Board (HSRB) [1], the team is surveying potential candidate models and novel strategies that generate metrics suitable for supporting decision making related to how the CHP system may influence human system performance risk. One such investigation includes classic Human Reliability Analysis (HRA) models. Traditionally, HRA methods estimate the occurrence of human errors and their impact on the success of an activity when designing and operating a system. While humans perceive, interpret, decide on, and carry out a course of action, the factors affecting performance and error likelihood are commonly referred to as performance shaping factors (PSFs). Originally developed to alleviate safety concerns related to nuclear power plant operations, HRA methods such as THERP [2] and CREAM [3] dismantle an activity into tasks, requiring elemental steps to be executed, and assess their failure due to predefined PSFs. In this study, we compare generic HRA methods and those that incorporate some human spaceflight aspects, such as sleep conditions (SCREAM [4]), with respect to how they may be adopted to capture performance with an intention to mitigate detrimental outcomes elucidated by the HSRB DAGs. We suggest strategies to quantify astronaut performance specific to spaceflight activities and illustrate how such concepts may help in optimizing the CHP system capabilities with respect to Artemis missions.

dag↗

NASA Exploration Toilet Hardware Status and Crew Feedback from ISS Artemis-2 Demonstration

The Universal Waste Management System (UWMS), ISS operational nomenclature “Toilet”, was initially installed on the International Space Station (ISS) in 2020 with final installation completed in 2021. Technical progress continues to be made with each on-orbit operation and will ultimately culminate with nominal US crew use of the hardware on ISS. During 2023, the Artemis-2 Demonstration was started, and this paper discusses issues encountered, on-orbit troubleshooting, subsequent ground failure investigation and proposed repairs as well as near-term plans to resume the Artemis-2 demo. Also discussed is an update to the commercial-off-the-shelf (COTS) Conductivity Monitor (CCM) which is planned to be flown for the resumption of the demo along with additional UWMS hardware and Toilet Integration Hardware (TIH). An updated design of the commode seat and fecal bag for Artemis-2 UWMS will be demonstrated on ISS and a summary of the hardware is included in the paper. Use of the hardware during the first days of the aborted demonstration by crewmembers and feedback received is summarized as well as hardware updates resulting from that feedback. The paper will also provide an overview of the demo results to date that inform the Orion-installed UWMS unit and future manifesting of consumables for both Orion and ISS.

Toilet↗

Where and How Well Do Cabin Crew Sleep During Long-Haul Flights?

INTRODUCTION: Sleep loss and circadian disruption pose a significant risk in aviation. Many studies have shown that inflight rest locations influence alertness and performance among pilots, but few studies have evaluated cabin crew. The aim of this research was to assess sleep outcomes among cabin crewmembers sleeping in a bunk during both outbound and inbound compared to alternating sleep in a bunk or a jump seat during one long-haul route. METHODS: Twenty-nine (5 male) cabin crewmembers (Mage = 30.61, SD = 2.91) flew the same long-haul route (outbound and inbound) with a flight duration of 10:41 (± 0:14) hours. Participants were randomly assigned to fly on an aircraft with a bunk in both directions or to fly an aircraft with a bunk in one direction and with a high comfort jump seat (HCJS) in the other direction for their sleep opportunity. They wore an Actiwatch throughout the entire study and completed a sleep diary at bedtime and upon waking for each sleep opportunity. Seventy-seven percent of the flights had a bunk and 23% had a HCJS. A series of mixed-effects models were performed to assess the differences in several sleep parameters when crewmembers slept in the bunk during both directions of the flight (bunk-only) compared to sleep obtained in the HCJS during one direction and bunk in the other (bunk+HCJS). RESULTS: Fifty-seven flights were included in the analyses. There were significant differences between sleep time (b = 22.56, SE = 9.07, p = .02, Hedges’ g = -0.65) and sleep efficiency (b = 16.75, SE = 4.49, p = .001, Hedges’ g = -1.07) obtained in bunk-only vs. bunk+HCJS. Crewmembers obtained more sleep and had better sleep efficiency when they slept only in the bunk compared to bunk+HCJS. DISCUSSION: Our results showed that cabin crewmembers slept longer and had better sleep efficiency when they used the bunk. Further research is needed to understand how subjective sleepiness and subsequent performance are influenced by sleep opportunity in a bunk-only compared to bunk+HCJS.

long-haul↗

NASA Exploration Hardware Status and Crew Feedback from Artemis-2 Demonstration

The Universal Waste Management System (UWMS), ISS operational nomenclature “Toilet”, was initially installed on the International Space Station (ISS) in 2020 with final installation completed in 2021. Technical progress continues to be made with each on-orbit operation and will ultimately culminate with nominal US crew use of the hardware on ISS. During 2023, the Artemis-2 Demonstration was started, and this paper discusses issues encountered, on-orbit troubleshooting, subsequent ground failure investigation and proposed repairs as well as near-term plans to resume the Artemis-2 demo. Also discussed is an update to the commercial-off-the-shelf (COTS) Conductivity Monitor which is planned to be flown for the resumption of the demo along with additional UWMS hardware and Toilet Integration Hardware (TIH). An updated design of the commode seat and fecal bag for Artemis-2 UWMS will be demonstrated on ISS and a summary of the hardware is included in the paper. Use of the hardware during the first days of the aborted demonstration by crewmembers and feedback received is summarized as well as hardware updates resulting from that feedback. The paper will also provide an overview of the demo results to date that inform the Orion-installed UWMS unit and future manifesting of consumables for both Orion and ISS.

Toilet↗

Crew Health and Performance (CHP) Technology Roadmaps

The Environmental Control and Life Support System (ECLSS) – Crew Health and Performance (CHP) Systems Capability Leadership Team (SCLT) is a community of practice (not a funded program) sponsored by Headquarters to develop, retain, and infuse the ECLSS and CHP capabilities necessary to enable the human exploration of the Moon and Mars through the integration and empowerment of experts across NASA, other government agencies, commercial industry, and academia. The goals of the SCLT are as follows: Use the Architecture Definition Document use cases and functions to identify gaps in NASA’s current technological capabilities to meet Agency objectives and develop strategies and roadmaps for closing such gaps Make technical/strategic recommendations on ECLSS and CHP technology development efforts and investments for PPBE, acquisition strategies, and leveraging NASA’s critical capabilities Establish key performance parameters and participate in key program and project reviews Maintain cognizance of relevant ECLSS and CHP national and international technology activities in government, industry, and academia, specifically, emerging innovations and technologies, trends, and opportunities Coordinate with commercial and international partners to identify areas of mutual interest and cooperation Support future mission and system architecture studies for human exploration This document is intended to be a comprehensive overview of the strategic development plans, or Roadmaps, of key technologies and capabilities identified by the SCLT. Each Roadmap is organized by Capability Gap as the gap name and number appears in STARPort, follows a fiscal year timeline, and displays any additional information on milestones, decision points, or important details on the right-hand side of the page. The Roadmaps should be used to facilitate discussion, decision making, and planning for programs and development projects, but are not expected to accurately depict the details and statuses of the projects and tasks appearing within the plans.

Human Health and Performance↗

Artemis III and IV Crew Health and Performance System Model Development

To maintain Crew Health and Performance (CHP) during an Artemis mission, the NASA Human Research Program (HRP) and Exploration Medical Capabilities (ExMC) element recognize the challenge that many different vehicles, habitats, and operational groups must come together to develop and implement cross program capabilities. To address this challenge, the ExMC team created the prototype 2023 Artemis CHP System Model to analyze how human system requirements are implemented throughout an Artemis mission and help understand the effects of changing an individual vehicle or habitat requirement on a full mission. Since presenting this work at the 2024 HRP Investigators’ Workshop, ExMC has continued this effort, now called the Artemis III and IV CHP System Model, to better support its operational end users within the NASA Human Health and Performance Directorate (HHPD) workforce. In this presentation, we will recapitulate how visualizing requirements and their relationships using a Model-Based Systems Engineering approach (MBSE) serves to improve understanding of an Artemis mission’s CHP capabilities along with discussion on updates made to the model to increase accessibility for users within HHPD so that it may be used in the development of cross program CHP capabilities at NASA.

Crew Health and Performance↗

The reactivity of experimentally reduced lunar regolith simulants: Health implications for future crewed missions to the lunar surface

Crewed missions to the Moon may resume as early as 2026 with NASA's Artemis III mission, and lunar dust exposure/inhalation is a potentially serious health hazard that requires detailed study. Current dust exposure limits are based on Apollo-era samples that spent decades in long-term storage on Earth; their diminished reactivity may lead to underestimation of potential harm that could be caused by lunar dust exposure. In particular, lunar dust contains nanophase metallic iron grains, produced by “space weathering”; the reactivity of this unique component of lunar dust is not well understood. Herein, we employ a chemical reduction technique that exposes lunar simulants to heat and hydrogen gas to produce metallic iron particles on grain surfaces. We assess the capacity of these reduced lunar simulants to generate hydroxyl radical (OH*) when immersed in deionized (DI) water, simulated lung fluid (SLF), and artificial lysosomal fluid (ALF). Lunar simulant reduction produces surface-adhered metallic iron “blebs” that resemble nanophase metallic iron particles found in lunar dust grains. Reduced samples generate ~5–100× greater concentrations of the oxidative OH* in DI water versus non-reduced simulants, which we attribute to metallic iron. SLF and ALF appear to reduce measured OH*. The increase in observed OH* generation for reduced simulants implies high oxidative damage upon exposure to lunar dust. Low levels of OH* measured in SLF and ALF imply potential damage to proteins or quenching of OH* generation, respectively. Reduction of lunar dust simulants provides a quick cost-effective approach to study dusty materials analogous to authentic lunar dust.

54 ENVIRONMENTAL SCIENCES↗