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NASA NTRS2018

Vision 2040: A Roadmap for Integrated, Multiscale Modeling and Simulation of Materials and Systems

Over the last few decades, advances in high-performance computing, new materials characterization methods, and, more recently, an emphasis on integrated computational materials engineering (ICME) and additive manufacturing have been a catalyst for multiscale modeling and simulation-based design of materials and structures in the aerospace industry. While these advances have driven significant progress in the development of aerospace components and systems, that progress has been limited by persistent technology and infrastructure challenges that must be overcome to realize the full potential of integrated materials and systems design and simulation modeling throughout the supply chain. As a result, NASA's Transformational Tools and Technology (TTT) Project sponsored a study (performed by a diverse team led by Pratt & Whitney) to define the potential 25-year future state required for integrated multiscale modeling of materials and systems (e.g., load-bearing structures) to accelerate the pace and reduce the expense of innovation in future aerospace and aeronautical systems. This report describes the findings of this 2040 Vision study (e.g., the 2040 vision state; the required interdependent core technical work areas, Key Element (KE); identified gaps and actions to close those gaps; and major recommendations) which constitutes a community consensus document as it is a result of over 450 professionals input obtain via: 1) four society workshops (AIAA, NAFEMS, and two TMS), 2) community-wide survey, and 3) the establishment of 9 expert panels (one per KE) consisting on average of 10 non-team members from academia, government and industry to review, update content, and prioritize gaps and actions. The study envisions the development of a cyber-physical-social ecosystem comprised of experimentally verified and validated computational models, tools, and techniques, along with the associated digital tapestry, that impacts the entire supply chain to enable cost-effective, rapid, and revolutionary design of fit-for-purpose materials, components, and systems. Although the vision focused on aeronautics and space applications, it is believed that other engineering communities (e.g., automotive, biomedical, etc.) can benefit as well from the proposed framework with only minor modifications. Finally, it is TTT's hope and desire that this vision provides the strategic guidance to both public and private research and development decision makers to make the proposed 2040 vision state a reality and thereby provide a significant advancement in the United States global competitiveness.

multi-scale modeling↗
NASA NTRSDate not supplied

In Situ Resource Utilization (ISRU) Envisioned Future Priorities

The National Aeronautics and Space Administration (NASA) of the United States of America (US) has initiated the Artemis Moon to Mars program to send astronauts (the first woman and person of color) back to the lunar surface, create a sustainable human lunar exploration program, and lead the first human exploration mission to the Mars surface in the 2030’s. A major objective of this program is to characterize the resources that exist on the Moon and Mars, and learn how to utilize them for sustained and affordable exploration. Commonly known as In Situ Resource Utilization (ISRU), the search for, acquisition, and processing of resources in space has the potential to greatly reduce the dependency on transporting mission consumables and infrastructure from Earth, thereby reducing mission costs, risks, and dependency on Earth. Through the extraction and processing of resources into mission commodities such as rocket propellants, life support consumables, and fuel cell reactants, ISRU enhances and evolves the cis-lunar, lander, and surface transportation systems required for human exploration; expanding and ehancing HOW humans get to, explore, and return from the Moon. Through the extraction and processing of resources into metals, silicon, and other manufacturing and construction feedstock, ISRU enhances and allows for the expansion of critical infrastructure through in situ manufacturing and construction capabilities needed for WHAT humans do on the Moon and in cis-lunar space. Because of this, ISRU supports and enables commercial involvement beyond NASA and governmental agencies by both lowering the cost of sustained transportation to/from/on the Moon as well as supporting the market required for needing these transportation systems. To achieve this vision, NASA’s Space Technology Mission Directorate (STMD) ensures the coordinated development of ISRU and other critical space and surface infrastructure elements such as propulsion, power, manufacturing, construction, and robotics through the Strategic Technology Architecture Roundtable (STAR) process. Through STAR, an integrated framework and process has been created allowing for capabilities and technologies to be linked and assessed, gaps to be identified, specifications and metrics to be established, and provide a means to prioritize and implement technology development and missions. For lunar ISRU, three primary areas of development have been initiated, (1) understanding, mapping, extracting, and processing water and other volatiles found in polar permanently shadowed regions (PSRs), (2) methods, technologies to extract oxygen from regolith, and (3) methods, technologies, and use cases for metals, silicon, and other feedstock commodities extracted and produced from lunar resources. This presentation will briefly discuss the STAR process and elaborate on the current status and future plans for ISRU development, demonstration, and architecture implementation of NASA’s Envisioned Future Priorities plan for ISRU.

In Situ Resource Utilization↗
NASA NTRSDate not supplied

COSPAR Workshop Series on Refining Planetary Protection Requirements for Human Missions to Mars

COSPAR and its space agency partners are supporting a multi-year stepwise process devel-oping needed approaches to address planetary protection requirements for human missions beyond Earth orbit. The objective is to support incremental development from the current qualitative COSPAR planetary protection “Principles and Guidelines for Human Missions to Mars” to quantitative implementable planetary protection requirements for such future mis-sions. The workshops and meetings in this series have involved participants from NASA, ESA, JAXA and other national space agencies, as well as the scientific/technical community, and commercial/private enterprise stakeholders, based around three main topic areas: Microbial and Human Health Monitoring; Spacecraft Technology and Operations, and; Natural Trans-port of Contamination at Mars. This presentation provides a status update on the findings of the COSPAR Meetings on this topic to date. First, the identification and prioritization of knowledge gaps will be summarized. Next, where a knowledge gap is to be addressed by new measurements, example descriptions of measurements needed to close the knowledge gaps (and instruments necessary to make those measurements) will be discussed. Where the knowledge gaps closure is based on Agency policy decisions, the scope of the decision-making parameters and process will be described. Lastly, the presentation will consider how the findings of the study series can be integrated into current and future space agency and COSPAR activities.

J. Andy Spry↗
NASA NTRS2018

2040 Vision: A Roadmap for Integrated, Multiscale Materials and System Modeling and Simulation

Over the last few decades, advances in high-performance computing, new materials characterization methods, and, more recently, an emphasis on integrated computational materials engineering (ICME) and additive manufacturing have been a catalyst for multiscale modeling and simulation-based design of materials and structures in the aerospace industry. While these advances have driven significant progress in the development of aerospace components and systems, that progress has been limited by persistent technology and infrastructure challenges that must be overcome to realize the full potential of integrated materials and systems design and simulation modeling throughout the supply chain. As a result, NASA's Transformational Tools and Technology (TTT) Project sponsored a study (performed by a team led by Pratt & Whitney) to define the potential 25-year future state required for integrated multiscale modeling of materials and systems (e.g., load-bearing structures) to accelerate the pace and reduce the expense of innovation in future aerospace and aeronautical systems. This talk will describe the findings of this 2040 Vision study (e.g., the 2040 vision state; the required interdependent core technical work areas, Key Element (KE); associated critical gaps and actions to close those gaps; and major recommendations). This roadmap is a community consensus document and is a result of over 450 professionals input obtain via: i) four society workshops (AIAA, NAFEMS, and two TMS), ii) community-wide survey, and iii) the establishment of 9 expert panels (one per key element) consisting on average 10 non-team members from academia, government and industry to review, update content, and prioritize gaps and actions. It is NASA's hope and desire that this roadmap provides the strategic guidance to both public and private research and development decision makers to make the proposed 2040 vision state a reality and thereby provide a significant advancement in the United States global competitiveness.

Multiscale Modeling↗
NASA NTRSDate not supplied

Sustaining Thermal Protection Systems Needed for Uranus Probes

Summary: Achieving Uranus in-situ science objectives through deploying probes in the atmosphere requires thermal protection systems capable of withstanding extreme entry environments. NASA’s 3-D Woven based thermal protection systems (TPS), developed specifically to meet this challenge, are mature, efficient, and capable of withstanding such entry. These science-enabling capabilities need to be sustained, otherwise mission implementation risk may increase to the point that the mission is untenable. The heatshield technology has been developed in concert with industry, and manufacturing processes have been technology transferred. Current technology readiness does not guarantee future availability. Sustainment requires maintaining expertise within NASA as well as ensuring that proven industrial expertise and capabilities will be readily available in the future. A constant awareness and risk assessment followed by risk mitigation are required. The scientific community needs to be aware of these challenges. It needs to engage NASA to ensure these capabilities will be available when needed. As was the case with the atrophy of heritage carbon phenolic that led to developing the 3-D Woven capabilities, our vigilance is again needed to sustain these enabling TPS capabilities for Uranus and for other missions. Background: NASA invested in and developed Heatshield for Extreme Entry Environment Technology (HEEET) TPS that was matured to TRL 6 in 2019 as a tiled system with seams and gap-fillers. Manufacturing readiness included development of specialized looms, molding, and infusion processes using commercial partners. In support of the Mars Sample Return mission, a single-layer, seamless, single-piece variant referred to as 3MDCP (3-D woven Mid-Density Carbon-Phenolic) was developed and is limited to a 1.3m maximum diameter scale due to weaving width limitations of 80”. Molding techniques developed to transform a flat, 2”-thick 3-D woven preform into a sphere-cone shape prior to phenolic resin infusion has been demonstrated. A team at NASA Ames is currently working with industry to demonstrate infusion at full-scale. By 2026, 3MDCP will be at a high level of maturity in technical, manufacturing, and integration readiness as well as material characterization. HEEET and 3MDCP for Uranus Entry: Several system studies have evaluated and baselined 3-D Woven TPS for Uranus entry, both HEEET as well as 3MDCP. If the aeroshell carrying the descent probe is 1.3m or less, then 3MDCP is a very capable and the most mass-efficient choice. If the aeroshell is bigger than 1.3m diameter, then HEEET can meet the mission need as it allows for an aeroshell of any diameter. HEEET and 3MDCP are capable of Saturn in-situ science missions prioritized in the New Frontiers-5 draft Announcement of Opportunity (AO) and if Saturn is the mission of choice, there is a pathway for sustaining the capability. Capability Sustainment: Given NASA’s current budgetary constraints, the postponement of the next New Frontiers AO to no earlier than 2026 and the unknown delay in starting the UOP flagship effort point to potential gap years for the HEEET and 3MDCP capabilities. The first step in capability sustainment is to understand the risks as they emerge, assess those risks, and develop plans to mitigate them. Keeping the science community, who are interested in UOP as well as the larger Giant Planet missions, informed of the emerging challenges requires continuous risk assessment/mitigation. Without these steps, atrophy is more likely within the industrial partners with which NASA has partnered. This presentation will provide more details as well as steps NASA can take to minimize the impact to the UOP mission.

Ethiraj Venkatapathy↗
NASA NTRS1991

Orbit transfer rocket engine technology program: Automated preflight methods concept definition

The possibility of automating preflight engine checkouts on orbit transfer engines is discussed. The minimum requirements in terms of information and processing necessary to assess the engine'e integrity and readiness to perform its mission were first defined. A variety of ways for remotely obtaining that information were generated. The sophistication of these approaches varied from a simple preliminary power up, where the engine is fired up for the first time, to the most advanced approach where the sensor and operational history data system alone indicates engine integrity. The critical issues and benefits of these methods were identified, outlined, and prioritized. The technology readiness of each of these automated preflight methods were then rated on a NASA Office of Exploration scale used for comparing technology options for future mission choices. Finally, estimates were made of the remaining cost to advance the technology for each method to a level where the system validation models have been demonstrated in a simulated environment.

Erickson, C. M.↗
NASA NTRS2021

Scheduling and Operations of the ECOSTRESS Mission

This paper describes the development and use of an automated scheduling system for the National Aeronautics and Space Administration’s (NASA) ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) mission. Key to the success of the ECOSTRESS mission has been the use of automated scheduling in mission analysis pre-launch, and in successful operations where automated scheduling was deployed to address several operational challenges. ECOSTRESS uses an adaptation of the Compressed Large-scale Activity Scheduling and Planning (CLASP) system to automatically select science observations respecting area and point target priorities as well as visibility, illumination, onboard storage, and radiation constraints to satisfy high-level prioritized science campaigns. The ECOSTRESS scheduler was used pre-launch to predict the effectiveness of alternative formulations of science campaign definitions accounting for the impact of data volume, keepout, and orbit/illumination/visibility constraints to derive the initial operational science campaign definitions and priorities. The scheduler was then used after instrument checkout for operations. ECOSTRESS has faced multiple operational challenges relating to instrument firmware and hardware, and the scheduler has been updated several times to address these challenges. The instrument Mass Storage Units (MSUs) had operational issues, requiring the scheduler to plan for and schedule commands to handle intricacies of data management. After many months of operations, both MSUs on the instrument became non-functioning and the firmware of the instrument was updated to bypass the MSUs. A further update to the ECOSTRESS scheduler enabled the scheduler to operate in this new operations mode. The ECOSTRESS scheduler has also been updated to improve handling of along-track uncertainty inherent in International Space Station operations. The flexibility and ease of updating of the automated scheduler has been a significant contributor to successful operations of the ECOSTRESS mission.

Padams, Jordan↗
NASA NTRS1997

T/BEST: Technology Benefit Estimator for Composites and Applications to Engine Structures

Progress in the field of aerospace propulsion has heightened the need to combine advanced technologies. These benefits will provide guidelines for identifying and prioritizing high-payoff research areas, will help manage research with limited resources, and will show the link between advanced and basic concepts. An effort was undertaken at the NASA Lewis Research Center to develop a formal computational method, T/BEST (Technology Benefit Estimator), to assess advanced aerospace technologies, such as fibrous composites, and credibly communicate the benefits of research. Fibrous composites are ideal for structural applications such as high-performance aircraft engine blades where high strength-to-weight and stiffness-to-weight ratios are required. These factors - along with the flexibility to select the composite system and layup, and to favorably orient fiber directions - reduce the displacements and stresses caused by large rotational speeds in aircraft engines.

Chamis, Christos↗
NASA NTRSDate not supplied

Motor Configuration Selection for A New Technical Challenge to Develop A 5 MW Cryogenic Motor and Drive

Due to aviation’s appreciable and growing share of humanity’s impact on our environment and estimates that CO2emissions only account for 34% of aviation’s total effective radiative forcing [1], there is a need to reach beyond climate goals that focus only on CO2emissions, such as the US Aviation Climate Action Plan’s [3] goal to reach net-zero carbon emissions by 2050.There is motivation to develop technology that pushes toward future large transport aircraft with net zero climate impact that are highly electrified (i.e., have higher power electrical propulsion system components). This paper describes a new, 6-year technical challenge to address this need by developing a 5 MW superconducting motor and cryogenic drive. Section 1 will detail the motivation for this work. Section 2 will describe the technical challenge and the selected specifications for the motor. Section 3 will present the results of a motor configuration trade study and the down selection of one configuration to develop a detailed design for. The technical challenge focuses on the design of a5 MW superconducting motor and cryogenic drive and demonstration of it at a 2+ MW scale to achieve TRL 3. Both fully superconducting (superconducting stator and rotor) and fully cryogenic (superconducting rotor and cryogenic stator) machine configurations will be explored. An emphasis will be placed on addressing the key tall poles for high power superconducting machines. Further details will be included in the full paper. The requirements and goals of the motor will be detailed. The rated speed (2,000 to 3,000 rpm) is defined to be appropriate for directly driving multi-MW fans or propellers. A range of rated speed is permitted because the motor is not designed for a specific aircraft and to provide design flexibility if AC losses in the stator winding are found to be a significant constraint (i.e., a lower speed can be selected to reduce electrical frequency). Relatively conservative requirements for efficiency (99%) and specific power (20 kW/kg) are defined, because TRL advancement and pushing toward flight readiness is emphasized over performance optimization. However, more aggressive efficiency and specific power goals are specified (99.9% and 40 kW/kg). The 3rd section will present the results of a motor configuration trade study. The study started with a qualitative assessment of sixteen motor configurations based on geometric, mechanical, thermal, and electromagnetic criteria. This assessment has been completed with three evaluators scoring all nine criteria. A configuration down select was made by prioritizing the sixteen configurations into four tiers based on each configuration’s total score and consideration of manufacturability, complexity, and support hardware (e.g., rotary vacuum seals, bearings). Configurations in priority A and B will be further evaluated through quantitative assessments, whereas those in priority C will only be further evaluated if time permits and priority D will not be further evaluated. Eight of the sixteen configurations were down selected for quantitative assessment, which will include analytical calculations and low-to moderate-fidelity finite element analysis to produce a preliminary Pareto front of efficiency versus specific power for each configuration. This assessment emphasizes the calculation of AC losses in the stator winding and an exploration of thermal management approaches to remove that heat and maintain cryogenic temperature. The final paper will include a description of each motor configuration that was considered. The quantitative assessments are underway, and an assessment of one configuration is complete for multiple stator conductor options. The remaining assessments are scheduled to be completed by late March so that the final down select to one configuration can be included in this paper.

Net Zero↗
NASA NTRS1990

A function-based approach to cockpit procedure aids

The objective of this research is to develop and test a cockpit procedural aid that can compose and present procedures that are appropriate for the given flight situation. The procedure would indicate the status of the aircraft engineering systems, and the environmental conditions. Prescribed procedures already exist for normal as well as for a number of non-normal and emergency situations, and can be presented to the crew using an interactive cockpit display. However, no procedures are prescribed or recommended for a host of plausible flight situations involving multiple malfunctions compounded by adverse environmental conditions. Under these circumstances, the cockpit procedural aid must review the prescribed procedures for the individual malfunction (when available), evaluate the alternatives or options, and present one or more composite procedures (prioritized or unprioritized) in response to the given situation. A top-down function-based conceptual approach towards composing and presenting cockpit procedures is being investigated. This approach is based upon the thought process that an operating crew must go through while attempting to meet the flight objectives given the current flight situation. In order to accomplish the flight objectives, certain critical functions must be maintained during each phase of the flight, using the appropriate procedures or success paths. The viability of these procedures depends upon the availability of required resources. If resources available are not sufficient to meet the requirements, alternative procedures (success paths) using the available resources must be constructed to maintain the critical functions and the corresponding objectives. If no success path exists that can satisfy the critical functions/objectives, then the next level of critical functions/objectives must be selected and the process repeated. Information is given in viewgraph form.

Phatak, Anil V.↗
NASA NTRS2016

UAS Integration in the NAS Project: DAA-TCAS Interoperability "mini" HITL Primary Results

At the May 2015 SC-228 meeting, requirements for TCAS II interoperability became elevated in priority. A TCAS interoperability workgroup was formed to identify and address key issues/questions. The TCAS workgroup came up with an initial list of questions and a plan to address those questions. As part of that plan, NASA proposed to run a mini HITL to address display, alerting and guidance issues. A TCAS Interoperability Workshop was held to determine potential display/alerting/guidance issues that could be explored in future NASA mini HITLS. Consensus on main functionality of DAA guidance when TCAS II RA occurs. Prioritized list of independent variables for experimental design. Set of use cases to stress TCAS Interoperability.

human systems integration↗
NASA NTRS1994

Solar System Exploration Technology Requirements and Planning Process

The NASA Office of Space Science, in alliance with the Office of Advanced Concepts and Technology, has developed an Integrated Technology Strategy to guide its investment in technology for space science missions. This strategy establishes goals and strategic objectives that ensure that NASA and the nation derive the greatest possible scientific and economic benefits from investments in space science missions and technologies. Within the Office of Space Science, the Solar System Exploration Division in collaboration with the Office of Space Access and Technology, is developing a Technology Plan to implement these goals and to identify specific goals and to identify specific technology needs for solar system missions. This paper describes the philosophy, processes, and preliminary results of the systematic process being established for the identification and prioritization of solar system exploration technology needs.

space↗
NASA NTRS2014

Project Assessment Framework through Design (PAFTD) - A Project Assessment Framework in Support of Strategic Decision Making

Research and development organizations that push the innovation edge of technology frequently encounter challenges when attempting to identify an investment strategy and to accurately forecast the cost and schedule performance of selected projects. Fast moving and complex environments require managers to quickly analyze and diagnose the value of returns on investment versus allocated resources. Our Project Assessment Framework through Design (PAFTD) tool facilitates decision making for NASA senior leadership to enable more strategic and consistent technology development investment analysis, beginning at implementation and continuing through the project life cycle. The framework takes an integrated approach by leveraging design principles of useability, feasibility, and viability and aligns them with methods employed by NASA's Independent Program Assessment Office for project performance assessment. The need exists to periodically revisit the justification and prioritization of technology development investments as changes occur over project life cycles. The framework informs management rapidly and comprehensively about diagnosed internal and external root causes of project performance.

Depenbrock, Brett T.↗
NASA NTRS2016

UAS Integration into the NAS: Detect and Avoid Display Evaluations in Support of SC-228 MOPS Development

At the May 2015 SC-228 meeting, requirements for TCAS II interoperability became elevated in priority. A TCAS interoperability work group was formed to identify and address key issuesquestions. The TCAS work group came up with an initial list of questions and a plan to address those questions. As part of that plan, NASA proposed to run a mini HITL to address display, alerting and guidance issues. A TCAS Interoperability Workshop was held to determine potential displayalertingguidance issues that could be explored in future NASA mini HITLS. Consensus on main functionality of DAA guidance when TCAS II RA occurs. Prioritized list of independent variables for experimental design. Set of use cases to stress TCAS Interoperability.

detect and avoid↗
NASA NTRS2016

Nasa Space Flight Instruments: Cost Time Trends

Are NASA’s space flight instruments becoming cheaper or more expensive as time marches forward? After analyzing the costs of hundreds of instruments launched over the last 30 years, the short answer to this question is no… and yes. This paper gives a visual analysis of the cost time trends for various NASA space flight instrument types, such as optical, particles detectors, fields detectors and microwave instruments. In addition to the statistical approaches utilized, such as significance tests, cluster analysis and principle components analysis (PCA), we will also discuss the intangibles which are likely at play, including technological progress, NASA policy and the luck of the draw associated with mission manifests. This analysis was performed as the main driver for the NASA Instrument Cost Model (NICM) recent cost estimating model redesign. Started in 2004, the first version of NICM was based off of instruments launched from 1985-2005, or 20 years’ worth of data. As NICM hit its 10-year anniversary, we wanted to know: should NICM continue to only use the most recent 20 years’ worth of data (1995-2015)? Are instruments becoming cheaper or more expensive as time marches forward? There is evidence in favor of a drop in the median dollar-per-kg value across some instrument types, but little in others. Whereas further research is needed to substantiate, Particles and Optical-Planetary instrument types show moderate to strong evidence of a downward trend in dollar-per-kg. Further research is required to study the nature of this trend (shift, taper, cyclic, etc.). Little evidence for a similar downward trend was detected for Fields or Microwave instruments, or Optical instruments on Earth Orbiting spacecraft. We presented evidence in favor of a drop in the median dollar-per-kg value for Particles and Optical-Planetary instrument types. While similar evidence was weak at best for Fields and Microwave instruments. We can speculate as to the causes for this effect, but we are also equipped to begin to rule out, or at least prioritize, some of the suspected drivers. We observed, for Particles and Optical-Planetary instruments, that perhaps a launch manifest effect was playing part of the role in the observed decrease in dollar-per-kg over the years, noting that the more flagship class missions, which have more money to spend on their instruments, were seen in the earlier years in our data, versus the later years which were dominated by less expensive class missions. However, if this were a dominating driver, would we not have seen the downward trend in the Fields and Microwave instruments as well, which were drawn from that same launch manifest? The fact that we did not observe this helps us rule out the launch manifest effect, and other drivers, such as advances in technology, that seem to be more likely suspects. In that case, however, why would technology advances be helping the Particles and Optical-Planetary instruments only? Why would it not be impacting Optical-Earth Orbiting instruments? Further suspects were looked at as well and ruled out, such as the “Faster, Better, Cheaper”era of NASA development which did not seem to actually impact trends by instrument type on a dollar-perkg scale. VI. Future Work A. Time Series Detailed Statistical Assessment The analysis discussed above sets the foundation for a more rigorous time series analysis of the data. Time series analysis will further explore evidence to-date of time trends for the instrument types which showed the strongest indicators for a decrease in dollar-per-kg: Optical (Planetary) and Particles instruments. More than providing evidence and top-level significance tests, time series analysis would help elucidate what kind of trend that exists in the data, their significance and allow statistically based forecasting (see Figure 10)

Mrozinksi, Joseph↗
NASA NTRS2008

Adaptive QoS in 802.11e Wireless Networks for Lunar Communications

This slide presentation reviews the issues around Adaptive Quality of Service (QoS) in wireless networks for lunar communications, and how a dynamic 802.11e standard meets the requirements for all aspects of communications for lunar surface missions. This paper focuses on the use of Enhanced Distributed Channel Access (EDCA). It includes a description of an adaptive QoS Algorithm, a review of the set up of the simulation of the 802.11e standard, and the results of the simulation are included.

quality of service,↗
NASA NTRS2019

Restore-L Intern Final Report

Every year, approximately 20 satellites are retired because their propellants are exhausted. Primarily limited by fuel, the satellites are usually fully functioning otherwise. The lifetimes of satellites can be extended with the capability of refueling. Not only would refueling extend satellite lifetime, it would also provide future satellites flexibility to prioritize other elements of their missions. Restore-L is a Goddard Space Flight Center Satellite Servicing Projects Division mission with the primary objectives of developing tools, technologies, and techniques to extend the lifetime of satellites - even if they were not designed to be serviced in or- bit. Equipped with five key servicing technology elements, the Restore-L Servicing Vehicle will demonstrate industry-changing satellite servicing technologies. The primary goal of the Restore-L mission is to rendezvous with, grasp, refuel, and relocate a government-owned satellite to extend its lifetime. The Propellant Transfer Subsystem (PTS) is required to deliver measured amounts of fuel to the client satellite in a safe manner.

Negi, Abhay↗
NASA NTRS2023

UAM Instrument Flight Procedure Design and Evaluation in the Joby Flight Simulator

NASA’s Advanced Air Mobility (AAM) National Campaign (NC) partnered with Joby Aviation to test and evaluate different developmental candidate Urban Air Mobility (UAM) Instrument Flight Procedure (IFP) designs including new departure, enroute, approach and missed approach architectures using Joby’s high-fidelity engineering aircraft simulator. In conjunction with the simulator testing, this effort also evaluated related aspects such as charting, coding, and adherence to flight planning criteria. The test objectives were to assess the safety, efficiency, passenger comfort and noise of the different variations of the developmental IFPs. Safety-related measures include clearance from terrain and vertical obstructions, procedure flyability, and flight path conformance. Efficiency-related measures included time required, airspace volume required, and battery energy required. Passenger comfort and ride quality measures include roll/pitch angles, roll/pitch attitude change rates, and airspeeds prior to aggressive maneuvers, subjective pilot/passenger responses and acceleration forces. The noise impacts of the different IFPs will be interpolated/extrapolated using data from the simulator fed into a separate Joby acoustic software-based tool. Overall, several tradeoffs were identified and characterized between the different variations of the developmental IFP profiles. No single version of the developmental IFP structure scored highest across all measures listed above; rather, different IFP variations proved optimal for different measures, confirming that the best IFP depends on which specific measures are prioritized for a given aircraft, location and operation.

National Campaign↗