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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Validation of Fault-Tolerant Plans for Europa Clipper

The Europa Clipper mission will explore that icy moon in a series of brief flybys through the Jovian radiation belts. A single event upset in the spacecraft flight computer during these critical scientific periods could jeopardize the success of the mission. Rather than safing and awaiting operator intervention, the Clipper mission envisions limited onboard autonomy that can restore spacecraft state sufficiently to resume the encounter observation plan as rapidly as possible. The contingency plan is contained in an Activity Restart Timeline (ART) that is transmitted in parallel with the nominal plan, which must be co-validated jointly against all spacecraft state and resource constraints amid unpredictable fault timing. A prototype validation tool was built that leverages declarative spacecraft models and automated search techniques to find such potential inconsistencies in the unified contingent mission plan. Early validation results within motivating scenarios are presented.

Ferguson, Eric↗
NASA NTRSDate not supplied

Deep Learning-Based Negotiation Strategy Selection for Cooperative Conflict Resolution in Urban Air Mobility

This paper presents a collaborative conflict resolution technique using deep neural network-based intelligent search of the solution space. This approach offers a rapid convergence to a mutually acceptable solution for real-time conflict resolution, suitable for urban air mobility operations. Furthermore, the presented technique allows operational flexibility to the urban air mobility agents where these agents can collaboratively devise the solution via integrative negotiation, based on their local utility functions, as long as such a solution does not violate the global safety thresholds. The presented machine-to-machine negotiation method is built on our prior work on holistic assessment of the airspace and potential conflict detection implemented at-the-edge, onboard the unmanned aircraft systems. This paper extends the prior work to augment decision-making at-the-edge, thereby, promising a true distributed control architecture for urban air mobility. In this approach, each agent (a) builds a potential in-flight conflict map, (b) identifies the conflicting agents, (c) dynamically prepares a list of alternatives based on its current utility functions, (d) negotiates with the conflicting agents to pick one of these alternatives, and (e) implements the negotiated alternative to mutually resolve the conflict. Note that such an approach does not require a contingency plan to be made pre-flight, as the conflict resolution strategies are decided and negotiated in real time based on the present state of the agent. The contingency plan, if available, can serve as an input to the real-time conflict resolution strategy formulation, and also can be used as a fallback plan in case the negotiation fails and the impacted agents need to switch to a rule-based/supervisory resolution mode from the discussed distributed resolution mode. The presented collaborative negotiation-based conflict resolution technique incorporates a time-dependent reward function to catalyze collaborative resolution by incentivizing the agents with local and global rewards beneficial to their business operations.

Advanced Air Mobility↗
NASA NTRSDate not supplied

IMPACT 1.0—Task Impairment: A Novel Approach for Assessing Impairment during Exploration-Class Missions

Exploration-class and International Space Station (ISS) missions have significantly different levels of associated medical risk for crewmembers. The Integrated Medical Model (IMM), the probabilistic risk assessment tool used for ISS medical trade-space analyses, uses a Functional Impairment (FI) metric to determine quality time lost should a crewmember be afflicted with a medical condition. While IMM-based FI has been successful for ISS operations, it has limitations when applied to exploration-class missions. As the National Aeronautics and Space Administration (NASA) looks ahead to Gateway, Artemis, and Martian missions, a novel, dynamic, and mission-appropriate impairment paradigm is necessary for accurate contingency planning. This paradigm, Task Impairment (TI), fulfills that need by utilizing mission-specific tasks. TI will allow future capability for a loss of mission metric, previously not available with IMM. TI serves as a replacement metric for FI within IMPACT, the next-generation trade-space analysis tool suite created to replace the IMM. IMPACT significantly increases the fidelity of probabilistic risk assessment for exploration-class missions. The Human Exploration of Mars Preliminary List of Crew Tasks (MTL, a source of 1100+ exploration-class mission-specific tasks for crewmembers) was used to calculate TI. Using the Task List, 18 individual Human System Categories were identified as being required to perform each task (e.g., Cardiopulmonary, Cognitive, etc.). Each of the 1200+ tasks were mapped to the Human System categories listed in the Task List. The total number of tasks in each category were tallied to determine how many tasks required each Human System. Lastly, each of the 120 medical conditions from the IMPACT condition list were mapped to the Human System categories to complete the TI calculation. NASA subject matter experts across five medical specialties established consensus for the mapping of each condition. The resulting total tasks impaired by each condition were used to calculate discrete TI values. This process was repeated for each of the four severity/resource utilization variants of each condition, and for each of the three phases of clinical care. Through this process, discrete TI values were calculated for each of the 120 IMPACT medical conditions and their variants. The Task Impairment metric provides higher fidelity, dynamic utility, and quicker analysis of medical impairment compared to the previous Functional Impairment metric used for the Integrated Medical Model. TI will be used for higher fidelity medical impairment analysis and contingency planning during Lunar, Martian, and other long-term exploration-class missions.

William L Fernandez↗
DOE OSTI2023

Emerging Best Practices for Electric Utility Planning with Climate Variability: A Resource for Utilities and Regulators

This report is intended to support electric utilities and regulators as they work together to increase the climate resilience of the power system in the United States. It focuses on best practice methods and examples of conducting utility forecasting with climate change (Section 2) as well as three overlapping types of electric utility planning for climate change: resource planning (Section 3), asset planning (Section 4), and contingency planning (Section 5). This report also addresses data development and access (Section 6), emerging pathways for planning including decision-making under deep uncertainty and storylines approaches (Section 7), regulatory considerations (Section 8), and coordination and innovative funding and cost sharing approaches to planning for climate variability (Section 9).

24 POWER TRANSMISSION AND DISTRIBUTION↗
NASA NTRS2002

Antarctic Exploration Parallels for Future Human Planetary Exploration: A Workshop Report

Four Antarctic explorers were invited to a workshop at Johnson Space Center (JSC) to provide expert assessments of NASA's current understanding of future human exploration missions beyond low Earth orbit. These explorers had been on relatively sophisticated, extensive Antarctic expeditions with sparse or nonexistent support infrastructure in the period following World War II through the end of the International Geophysical Year. Their experience was similar to that predicted for early Mars or other planetary exploration missions. For example: one Antarctic a expedition lasted two years with only one planned resupply mission and contingency plans for no resupply missions should sea ice prevent a ship from reaching them; several traverses across Antarctica measured more than 1000 total miles, required several months to complete, and were made without maps (because they did not exist) and with only a few aerial photos of the route; and the crews of six to 15 were often international in composition. At JSC, the explorers were given tours of development, training, and scientific facilities, as well as documentation at operational scenarios for future planetary exploration. This report records their observations about these facilities and plans in answers to a series of questions provided to them before the workshop.

Hoffman, Stephen J.↗
NASA NTRSDate not supplied

OSIRIS-REx Off-Nominal Re-entry Breakup Analysis

The Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) is a NASA asteroid sampling mission that launched on September 8, 2016. Its objectives are to study the asteroid Bennu for up to 505 days and obtain at least 60 grams of pristine regolith. The sample return to Earth is planned for September 2023. For contingency planning and risk assessment of a potential off-nominal Earth-return trajectory, a re-entry breakup analysis was performed to determine the response of the spacecraft to the environment and predict the breakup sequence and timeline, debris survival, and debris impact conditions. The failure scenario assumed a failure to separate between the bus and the sample return capsule (SRC), resulting in the combined bus+SRC configuration for the re-entry vehicle. Furthermore, consistent overburns or underburns were considered to produce three sets of initial conditions for the analysis consisting of nominal, steep, and shallow entry flight path angles. The results were compared to the breakup analysis performed for a similar vehicle, the Stardust spacecraft, which returned samples from the comet Wild 2 in 2006. This paper describes the OSIRIS-REx spacecraft and presents the results of the re-entry breakup analysis.

reentry breakup analysis↗
DOE OSTI2020

Impact of climate change on adaptive management decisions in the face of water scarcity

Reoccurring drought through the early 2000s has caused a serious water scarcity issue in the Colorado River Basin. Previous modeling studies have focused on the impact of climate change without considering the adaptive behaviors of farmers and under-utilized Indian water rights. Here, we use a coupled agent-based water resource model (ABM) to investigate how the adaptive decisions of farmers can affect water resource management under both climate change impacts and fully utilized Indian water right conditions. We used five General Circulation Model projections with RCP8.5 scenarios for the study. The results of farm-level decision-making showed different responses in irrigated areas that were changing due to climate change impact. While winter precipitation changes might partially explain the behavior changes, no specific pattern could be concluded based on their location. Also, farmers’ responses about annual water diversion showed more significant inter-year variation compared to irrigated areas. Basin-level metrics showed that climate change impacts will generally worsen water scarcity issues as measured in Navajo Reservoir storage, flow to Lake Powell, and instream flow requirement. But these basin-level water scarcity metrics cannot reflect individual farm-level impacts under climate change, which is why modeling the bottom-up management actions is necessary. When the under-utilized Indian water rights are fully used, it is more likely to trigger the shortage sharing agreement due to the higher tribal water depletion. Evaluation of model uncertainty and a more realistic setup for adaptive actions under drought contingency plans are suggested for future research.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2005

The Earth Science Afternoon Constellation Contingency Procedures

The Earth Science Afternoon Constellation comprises NASA missions Aqua, Aura, CloudSat and the Orbiting Carbon Observatory (OCO), the joint NASA/CNES mission CALIPSO and the CNES mission PARASOL. Both NASA and CNES offices are responsible for ensuring that contingency plans or other arrangements exist to cope with contingencies within their respective jurisdictions until the conclusion of all Afternoon Constellation operations. The Mission Operations Working Group, comprised of members from each of the missions, has developed the high-level procedures for maintaining the safety of this constellation. Each contingency situation requires detailed analyses before any decisions are made. This paper describes these procedures, and includes defining what constitutes a contingency situation, the pertinent parameters involved in the contingency analysis and guidelines for the actions required, based on the results of the contingency analyses.

Case, Warren F.↗
DOE OSTI2024

Best practices: Organizational execution

This article, the fourth and final installment in the DOE–IDEA series, focuses on organizational execution and how strong management practices, teamwork, and preparedness contribute to successful district energy systems. It highlights case studies from Ashley Energy and Cornell University to illustrate effective operational strategies. Ashley Energy demonstrates the importance of emergency preparedness and rapid response. After a major flood disrupted its plant, the organization restored service in under 72 hours by relying on pre-established plans, vendor relationships, and trained staff. The case emphasizes proactive contingency planning, understanding insurance processes, and empowering skilled personnel to improvise during crises. Cornell University’s example highlights the role of collaboration and transparency in long-term success. Its district energy system benefits from strong data sharing, real-time energy monitoring, and active involvement of faculty and students in system planning and innovation. This culture of teamwork and data-driven decision-making supports sustainability goals and continuous system improvement. Overall, the article shows that effective organizational execution—through preparedness, collaboration, and data transparency—is essential for maintaining reliable, efficient, and sustainable district energy systems.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
NASA NTRS2007

Haughton-Mars Project/NASA 2006 Lunar Medical Contingency Simulation: Equipment and Methods for Medical Evacuation of an Injured Crewmember

Introduction: Achieving NASA's Space Exploration Vision scientific objectives will require human access into cratered and uneven terrain for the purpose of sample acquisition to assess geological, and perhaps even biological features and experiments. Operational risk management is critical to safely conduct the anticipated tasks. This strategy, along with associated contingency plans, will be a driver of EVA system requirements. Therefore, a medical contingency EVA scenario was performed with the Haughton-Mars Project/NASA to develop belay and medical evacuation techniques for exploration and rescue respectively. Methods: A rescue system to allow two rescuer astronauts to evacuate one in incapacitated astronaut was evaluated. The systems main components were a hard-bottomed rescue litter, hand-operated winch, rope, ground picket anchors, and a rover-winch attachment adapter. Evaluation was performed on 15-25deg slopes of dirt with embedded rock. The winch was anchored either by adapter to the rover or by pickets hammered into the ground. The litter was pulled over the surface by rope attached to the winch. Results: The rescue system was utilized effectively to extract the injured astronaut up a slope and to a waiting rover for transport to a simulated habitat for advanced medical care, although several challenges to implementation were identified and overcome. Rotational stabilization of the winch was found to be important to get maximize mechanical advantage from the extraction system. Discussion: Further research and testing needs to be performed to be able to fully consider synergies with the other Exploration surface systems, in conducting contingency operations. Structural attachment points on the surface EVA suits may be critical to assist in incapacitated evacuation. Such attach points could be helpful in microgravity incapacitated crewmember transport as well. Wheeled utility carts or wheels that may be attachable to a litter may also aid in extraction and transport. Utilizing parts of the rover (e.g. seats) to deploy as a litter may be considered. Testing in simulated 1/6-g to determine feasibility of winch operation and anchor establishment will further reduce implementation uncertainties.

Chappell, S. P.↗
NASA NTRS2019

Autonomous Operating System (AOS)

The Autonomy Operating System (AOS) is a software system that enables core capabilities for the autonomous operations for an unmanned aircraft. It is based on the NASA cFS system and provides a higher-level layer of infrastructure and applications for the execution of flight plans, natural-language communication with Air Traffic Control, Diagnostics, Prognostics, and contingency planning.

Lowry, Michael R.↗
NASA NTRS2017

Initial Jupiter Orbit Insertion and Period Reduction Maneuver Plans for Juno

This paper describes the initial plans for the New Frontiers Juno mission at Jupiter. It includes the considerable contingency planning for mission recovery if the Jupiter Orbit Insertion (JOI) burn to place Juno into a large capture orbit were interrupted or terminated on a burn timer setting, and the options for the mission if the Period Reduction Maneuver (PRM) burn to achieve the final orbit period were terminated early. The analyses were based on the assumption that 14-day orbits were the desired operational orbit period.

Bordi, John J.↗
NASA NTRS1997

Maneuver design for Galileo Jupiter approach and orbital operations

Following the successful release of the Galileo probe, the navigation efforts were focused on the implementation of the critical Io approach and the Jupiter orbit insertion strategy. The actual in-flight events on the approach phase affected the strategy. The most significant event was the onboard tape recorder anomaly, and it is shown that this anomaly affected the plans and assumptions of the navigation strategy for the approach and orbit insertion. The analysis, constraints, contingency planning and design evolution of trajectory correction maneuvers which enabled the continuation of the mission, are reported on. The Jupiter approach and initial orbit navigation strategy is presented in order to verify the viability of the strategy under nominal circumstances, and future mission operations plans are described.

Wilson, Michael G.↗
NASA NTRS2007

An Evidence-based Approach to Developing a Management Strategy for Medical Contingencies on the Lunar Surface: The NASA/Haughton-Mars Project (HMP) 2006 Lunar Medical Contingency Simulation at Devon Island

The lunar architecture for future sortie and outpost missions will require humans to serve on the lunar surface considerably longer than the Apollo moon missions. Although the Apollo crewmembers sustained few injuries during their brief lunar surface activity, injuries did occur and are a concern for the longer lunar stays. Interestingly, lunar medical contingency plans were not developed during Apollo. In order to develop an evidence-base for handling a medical contingency on the lunar surface, a simulation using the moon-Mars analog environment at Devon Island, Nunavut, high Canadian Arctic was conducted. Objectives of this study included developing an effective management strategy for dealing with an incapacitated crewmember on the lunar surface, establishing audio/visual and biomedical data connectivity to multiple centers, testing rescue/extraction hardware and procedures, and evaluating in suit increased oxygen consumption. Methods: A review of the Apollo lunar surface activities and personal communications with Apollo lunar crewmembers provided the knowledge base of plausible scenarios that could potentially injure an astronaut during a lunar extravehicular activity (EVA). Objectives were established to demonstrate stabilization and transfer of an injured crewmember and communication with ground controllers at multiple mission control centers. Results: The project objectives were successfully achieved during the simulation. Among these objectives were extraction from a sloped terrain by a two-member crew in a 1 g analog environment, establishing real-time communication to multiple centers, providing biomedical data to flight controllers and crewmembers, and establishing a medical diagnosis and treatment plan from a remote site. Discussion: The simulation provided evidence for the types of equipment and methods for performing extraction of an injured crewmember from a sloped terrain. Additionally, the necessary communications infrastructure to connect multiple centers worldwide was established from a remote site. The surface crewmembers were confronted with a number of unexpected scenarios including environmental, communications, EVA suit, and navigation challenges during the course of the simulation which provided insight into the challenges of carrying out a medical contingency in an austere environment. The knowledge gained from completing the objectives will be incorporated into the exploration medical requirements involving an incapacitated astronaut on the lunar surface.

Scheuring, R. A.↗
NASA NTRS2007

Duration Limits for Orbital Flight: Current Considerations for the International Space Station

According to ISS documentation, long-duration missions are defined as missions exceeding 30 days. The ISS medical organization has set a 180-day limit for ISS missions from a medical perspective, with a possibility of planning missions of up to 220days with additional consideration. The ISS medical community does not currently consider changes to the existing duration constraints for ISS mission planning. However, longer stays on orbit may be highly desirable or even necessary in certain foreseeable operational circumstances. To develop a methodology for contingency planning, the ISS medical community, led by NASA, has identified medically relevant risks associated with extended stays of crewmembers aboard the ISS.

Smith, Gwen↗
NASA NTRS1971

The cryogenics analysis program for Apollo mission planning and analysis

The cryogenics analysis program was developed as a simplified tool for use in premission planning operations for the Apollo command service module. Through a dynamic development effort, the program has been extended to include real time and postflight analysis capabilities with nominal and contingency planning features. The technical aspects of the program and a comparison of ground test and mission data with data generated by using the cryogenics analysis program are presented. The results of the program capability to predict flight requirements also are presented. Comparisons of data from the program with data from flight results, from a tank qualifications program, and from various system anomalies that have been encountered are discussed. Future plans and additional considerations for the program also are included. Among these plans are a three tank management scheme for hydrogen, venting profile generation for Skylab, and a capability for handling two gas atmospheres. The plan for two gas atmospheres will involve the addition of the capability to handle nitrogen as well as oxygen and hydrogen.

Scott, W.↗
NASA NTRS1989

A Mars/phobos Transportation System

A transportation system will be necessary to support construction and operation of bases on Phobos and Mars beginning in the year 2020 or later. An approach to defining a network of vehicles and the types of vehicles which may be used in the system are presented. The network will provide a convenient, integrated means for transporting robotically constructed bases to Phobos and Mars. All the technology needed for the current plan is expected to be available for use at the projected date of cargo departure from the Earth system. The modular design of the transportation system provides easily implemented contingency plans, so that difficulties with any one vehicle will have a minimal effect on the progress of the total mission. The transportation network proposed consists of orbital vehicles and atmospheric entry vehicles. Initially, only orbital vehicles will participate in the robotic construction phase of the Phobos base. The Interplanetary Transfer Vehicle (ITV) will carry the base and construction equipment to Phobos where the Orbital Maneuvering Vehicles (OMV's) will participate in the initial construction of the base. When the Mars base is ready to be sent, one or more ITV's will be used to transport the atmospheric entry vehicles from Earth. These atmospheric vehicles are the One Way Landers (OWL's) and the Ascent/Descent Vehicles (ADV's). They will be used to carry the base components and/or construction equipment. The OMV's and the Orbital Transfer Vehicles (OTV's) will assist in carrying the atmospheric entry vehicles to low Martian orbit where the OWL's or ADV's will descent to the planet surface. The ADV's were proposed to accommodate expansion of the system. Additionally, a smaller version of the ADV class is capable of transporting personnel between Mars and Phobos.

Source record↗
NASA NTRS2004

Trajectory design for the Genesis backup orbit and proposed extended mission

In September 2004, the Genesis spacecraft will return to Earth with its collection of solar wind samples. If for some reason there are any difficulties with returning the samples to Earth during the nominal entry sequence, a contingency plan is in place for a second chance at a successful recovery. This paper will detail the processes used to generate possible backup trajectories, and provide a comparison of the contingency options examined through the course of the study.

Chung, Min-Kun J.↗