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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 163 records · Page 9

Dynamic Charging Rendezvous and Motion Planning for a Multi-AGV Team Including a Mobile Charging Host

Teams of automated battery-powered electric vehicles have the potential to execute complex mission tasks in off-road environments for agriculture, military, and other applications. Limited onboard energy reserves hinder their adoption in large-scale resource-constrained environments, where recharging is a necessity. It may be infeasible to install a network of static charging stations in off-road environments. For this reason, dedicated mobile host vehicles with charging capabilities are proposed as a means to increase range and capabilities of the multivehicle team. Here, in this study, we consider an ad hoc planning framework, where results from a high-confidence trajectory planner are leveraged to plan charging rendezvous between a host and other worker vehicles in a receding horizon fashion to provide high confidence that energy reserves will not be prematurely exhausted. The core problem is posed so as to minimize the impact of recharging on the mission in terms of task delays, overall energy utilization, and costs of fast charging. Through extensive Monte Carlo simulations of an off-road mission, we show a decrease in task delays without substantial increases in energy needs by updating the charging rendezvous plan during the mission. However, if updates are made too often, model mismatch may cause unnecessary cycling and mission failure.

Energy constraints↗

Final Review of FY23 ASC ATDM L2 Milestone, MRT #8541, ATDM Multiphysics Scaling on EAS-3

As displayed in the FY23 ASC Implementation Plan (IP) and the Milestone Reporting Tool (MRT), the milestone description and completion criteria state: Demonstrate the capability to execute mission-relevant calculations with a multiphysics code from the Ristra project at scale on the pre-El Capitan Early Access System 3 (EAS-3). These calculations must use the GPU hardware available on EAS-3, the AMD MI-250s, to achieve any reasonable performance.

97 MATHEMATICS AND COMPUTING↗

Small arms suppression project (LLNL final report)

US Special Operations Command (USSOCOM) was seeking a technological leap in small firearms weapon suppressor technology, because anticipated enemy capabilities are requiring the operators to have smaller detection cross sections to ensure the safe execution of missions. Suppressors have been developed almost exclusively through trial-and-error methods since the time of the original design by Hiram Maxim over one hundred years ago. Consequently USSOCOM deemed it prudent to perform a physicsbased study of weapon suppression to understand performance limits and possibly identify breakthrough technologies. Lawrence Livermore National Laboratory’s (LLNL’s) high performance production level computational tool called ALE3D (Arbitrary Lagrangian-Eulerian 3D and 2D) has unique physics models and numerical algorithms for modeling suppressor dynamics. The flexible and extendable code framework supports fully integrated hydrodynamics, heat transfer, solid and fluid dynamics, and chemistry that can be applied to simulating propellant-driven motion of a bullet down a gun barrel, the transfer of heat from the burning propellant to the barrel and suppressor, the chemistry of muzzle flash, and the shock/acoustic/optical signatures in the near-field. LLNL’s originally anticipated role was to augment ALE3D for this task, by developing the software and analysis methodologies specific to the simulation of blast and muzzle flash phenomena. It was believed that insights provided by our ALE3D simulations in tandem with a coordinated experimental component by our other team members from Oak Ridge National Laboratory (ORNL) and the U. S. Army Armament, Research, Development and Engineering Center (ARDEC), would have excellent prospects of yielding useful suppressor design improvements that could be transitioned to industry and utilized by US Special Operations Command. The three year effort has come to fruition with the development of revolutionary suppressor designs that far outperform any previous or current design by anyone outside this multi-lab team.

42 ENGINEERING↗

Shuttle derived launch vehicle wind tunnel tests

Studies are being conducted regarding new launch vehicle configurations which may effectively and economically share the delivery of payloads to orbit with the present Space Transportation System (STS). The role envisaged for these launch vehicles is related to the execution of missions whose requirements exceed the STS Shuttle capabilities, taking into account the delivery of much heavier or larger payloads. One class of advanced launch vehicles is configured to take advantage of the existing Shuttle hardware and facilities. Such vehicles are referred to as Shuttle Derived Vehicles (SDV). One version of an SDV consists of two STS elements, including the external tank (ET) and solid rocket boosters, and a cargo carrier. Attention is given to wind tunnel tests, which are being conducted with SDV sidemount configurations incorporating various size payload modules.

Tewell, J. R.↗

An efficient representation of spatial information for expert reasoning in robotic vehicles

The previous generation of robotic vehicles and drones was designed for a specific task, with limited flexibility in executing their mission. This limited flexibility arises because the robotic vehicles do not possess the intelligence and knowledge upon which to make significant tactical decisions. Current development of robotic vehicles is toward increased intelligence and capabilities, adapting to a changing environment and altering mission objectives. The latest techniques in artificial intelligence (AI) are being employed to increase the robotic vehicle's intelligent decision-making capabilities. This document describes the design of the SARA spatial database tool, which is composed of request parser, reasoning, computations, and database modules that collectively manage and derive information useful for robotic vehicles.

Scott, Steven↗

Research and technology

As the NASA center responsible for assembly, checkout, servicing, launch, recovery, and operational support of Space Transportation System elements and payloads, Kennedy Space Center (KSC) is placing increasing emphasis on KSC's research and technology program. In addition to strengthening those areas of engineering and operations technology that contribute to safer, more efficient, and more economical execution of the current mission, the technological tools needed to execute KSC's mission relative to future programs are being developed. The Engineering Development Directorate encompasses most of the laboratories and other KSC resources that are key elements of research and technology program implementation and is responsible for implementation of the majority of the projects in this KSC 1990 annual report. Projects under the following topics are covered: (1) materials science; (2) hazardous emissions and contamination monitoring; (3) biosciences; (4) autonomous systems; (5) communications and control; (6) meteorology; (7) technology utilization; and (8) mechanics, structures, and cryogenics.

Source record↗

Statistical modeling of software reliability

This working paper discusses the statistical simulation part of a controlled software development experiment being conducted under the direction of the System Validation Methods Branch, Information Systems Division, NASA Langley Research Center. The experiment uses guidance and control software (GCS) aboard a fictitious planetary landing spacecraft: real-time control software operating on a transient mission. Software execution is simulated to study the statistical aspects of reliability and other failure characteristics of the software during development, testing, and random usage. Quantification of software reliability is a major goal. Various reliability concepts are discussed. Experiments are described for performing simulations and collecting appropriate simulated software performance and failure data. This data is then used to make statistical inferences about the quality of the software development and verification processes as well as inferences about the reliability of software versions and reliability growth under random testing and debugging.

Miller, Douglas R.↗

SeaWiFS technical report series. Volume 17: Ocean color in the 21st century. A strategy for a 20-year time series

Beginning with the upcoming launch of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), there should be almost continuous measurements of ocean color for nearly 20 years if all of the presently planned national and international missions are implemented. This data set will present a unique opportunity to understand the coupling of physical and biological processes in the world ocean. The presence of multiple ocean color sensors will allow the eventual development of an ocean color observing system that is both cost effective and scientifically based. This report discusses the issues involved and makes recommendations intended to ensure the maximum scientific return from this unique set of planned ocean color missions. An executive summary is included with this document which briefly discusses the primary issues and suggested actions to be considered.

Abbott, Mark R.↗

Automated Testing Experience of the Linear Aerospike SR-71 Experiment (LASRE) Controller

System controllers must be fail-safe, low cost, flexible to software changes, able to output health and status words, and permit rapid retest qualification. The system controller designed and tested for the aerospike engine program was an attempt to meet these requirements. This paper describes (1) the aerospike controller design, (2) the automated simulation testing techniques, and (3) the real time monitoring data visualization structure. Controller cost was minimized by design of a single-string system that used an off-the-shelf 486 central processing unit (CPU). A linked-list architecture, with states (nodes) defined in a user-friendly state table, accomplished software changes to the controller. Proven to be fail-safe, this system reported the abort cause and automatically reverted to a safe condition for any first failure. A real time simulation and test system automated the software checkout and retest requirements. A program requirement to decode all abort causes in real time during all ground and flight tests assured the safety of flight decisions and the proper execution of mission rules. The design also included health and status words, and provided a real time analysis interpretation for all health and status data.

Larson, Richard R.↗

Venus and Beyond Using the Ariane ASAP Launch Capability

The cost of executing planetary missions in the next ten years is expected to decrease significantly. The principle reason is that new technology is reducing spacecraft mass while increasing capability. Another reason is that launch costs are expected to decrease. A move in this direction is to permit important planetary missions to fly as secondary payloads, and this opportunity is now provided by the French on the Ariane 5 using the Ariane Structure for Auxiliary Payloads (ASAP). The ASAP will fly on GEO missions, and can boost up to eight 100 kg (or 200 kg, if paired) payloads into the elliptical geosynchronous transfer orbit (GTO), which delivers large communication satellites to GEO. An efficient multi-burn method has been developed by this author to deliver these small spacecraft from GTO to Mars and other destinations. This method, referred to here as Moon-Earth Gravity Assist (MEGA), requires 3 or more major maneuvers together with close flybys of the earth and moon. An example for a Mars 2003 mission (not to scale) is shown in Figure 1, where, once in GTO, the first burn sends the spacecraft beyond the Moon to a distance of 1.2 million kilometers. At apogee, the second burn targets to an encounter with the Moon such that a swingby returns the spacecraft to the Earth with a 300 km perigee, and with an inclination such that a perigee burn will send the spacecraft off to Mars with the required escape velocity vector. Details of this method, specifically for Mars missions, can be found in Reference 3. A similar strategy works for Venus, with some caveats. This method is required to work for any Ariane 5 launch date over a three month period, to ensure a high probability of getting off the ground. The launch period is provided by fixing the Earth escape date (3rd burn), but allowing the high ellipse (beyond the Moon) period to vary by one or two months, and also allowing a one to two month wait time in GTO (or other orbit) before the first burn is performed. Figure 2 shows the trajectory profiles for the early and late GTO launch dates for a Mars 2003 mission. Venus. which is an inner planet, poses special problems for the MEGA process. The escape direction is reverse that of Earth's motion, and the GTO apogee arrival

Penzo, Paul A.↗

International Space Station ECLSS Operations Status - Increment OA

This paper describes Environmental Control and Life Support Systems (ECLSS) operations to date for preflight planning, international partner coordination and mission plan execution of the International Space Station (ISS). The focus is on the activities involved with the STS-88(2A) Space Shuttle Endeavor flight, the first delivery of the US segment of the ISS, which consists of the Pressurized Mating Adapter (PMA)/and Node 1 elements, and the delivery of the first Russian segment of the ISS, the FGB, a US-financed and Russian- built module.

Lamczyk, Philip C.↗

Gravity effects on cellulose assembly

The effect of microgravity on cellulose synthesis using the model system of Acetobacter xylinum was the subject of recent investigations using The National Aeronautics and Space Administration's Reduced Gravity Laboratory, a modified KC-135 aircraft designed to produce 20 sec of microgravity during the top of a parabolic dive. Approximately 40 parabolas were executed per mission, and a period of 2 x g was integral to the pullout phase of each parabola. Cellulose biosynthesis was initiated on agar surfaces, liquid growth medium, and buffered glucose during parabolic flight and terminated with 2.0% sodium azide or 50.0% ethanol. While careful ground and in-flight controls indicated normal, compact ribbons of microbial cellulose, data from five different flights consistently showed that during progression into the parabola regime, the cellulose ribbons became splayed. This observation suggests that some element of the parabola (the 20 sec microgravity phase, the 20 sec 2 x g phase, or a combination of both) was responsible for this effect. Presumably the cellulose I alpha crystalline polymorph normally is produced under strain, and the microgravity/hypergravity combination may relieve this stress to produce splayed ribbons. An in-flight video microscopy analysis of bacterial motions during a parabolic series demonstrated that the bacteria continue to synthesize cellulose during all phases of the parabolic series. Thus, the splaying may be a reflection of a more subtle alteration such as reduction of intermicrofibrillar hydrogen bonding. Long-term microgravity exposures during spaceflight will be necessary to fully understand the cellulose alterations from the short-term microgravity experiments.

manned↗

A Hardware-in-the-Loop Simulator for Software Development for a Mars Airplane

Draper Laboratory recently developed a Hardware-In-The-Loop Simulator (HILSIM) to provide a simulation of the Aerial Regional-scale Environmental Survey (ARES) airplane executing a mission in the Martian environment. The HILSIM was used to support risk mitigation activities under the Planetary Airplane Risk Reduction (PARR) program. PARR supported NASA Langley Research Center's (LaRC) ARES proposal efforts for the Mars Scout 2011 opportunity. The HILSIM software was a successful integration of two simulation frameworks, Draper's CSIM and NASA LaRC's Langley Standard Real-Time Simulation in C++ (LaSRS++).

Slagowski, Stefan E.↗

The Road to Launch and Operations of the Spitzer Space Telescope

Spitzer Space Telescope, the fourth and final of NASA's Great Observatories, and the cornerstone to NASA's Origins Program, launched on 25 August 2003 into an Earth-trailing solar orbit to acquire infrared observations from space. Spitzer has an 85cm diameter beryllium telescope, which operates near absolute zero utilizing a liquid helium cryostat for cooling the telescope. The helium cryostat, though designed for a 2.5 year lifetime, through creative planning now has an expected lifetime of 5.5 years. Spitzer has completed its in-orbit checkout/science verification phases and the first two years of nominal operations, becoming the first mission to execute astronomical observations from a solar orbit. Spitzer was designed to probe and explore the universe in the infrared utilizing three state of the art detector arrays providing imaging, photometry, and spectroscopy over the 3-160 micron wavelength range...

infrared↗

Monitoring System for Storm Readiness and Recovery of Test Facilities: Integrated System Health Management (ISHM) Approach

Severe weather events are likely occurrences on the Mississippi Gulf Coast. It is important to rapidly diagnose and mitigate the effects of storms on Stennis Space Center's rocket engine test complex to avoid delays to critical test article programs, reduce costs, and maintain safety. An Integrated Systems Health Management (ISHM) approach and technologies are employed to integrate environmental (weather) monitoring, structural modeling, and the suite of available facility instrumentation to provide information for readiness before storms, rapid initial damage assessment to guide mitigation planning, and then support on-going assurance as repairs are effected and finally support recertification. The system is denominated Katrina Storm Monitoring System (KStorMS). Integrated Systems Health Management (ISHM) describes a comprehensive set of capabilities that provide insight into the behavior the health of a system. Knowing the status of a system allows decision makers to effectively plan and execute their mission. For example, early insight into component degradation and impending failures provides more time to develop work around strategies and more effectively plan for maintenance. Failures of system elements generally occur over time. Information extracted from sensor data, combined with system-wide knowledge bases and methods for information extraction and fusion, inference, and decision making, can be used to detect incipient failures. If failures do occur, it is critical to detect and isolate them, and suggest an appropriate course of action. ISHM enables determining the condition (health) of every element in a complex system-of-systems or SoS (detect anomalies, diagnose causes, predict future anomalies), and provide data, information, and knowledge (DIaK) to control systems for safe and effective operation. ISHM capability is achieved by using a wide range of technologies that enable anomaly detection, diagnostics, prognostics, and advise for control: (1) anomaly detection algorithms and strategies, (2) fusion of DIaK for anomaly detection (model-based, numerical, statistical, empirical, expert-based, qualitative, etc.), (3) diagnostics/prognostics strategies and methods, (4) user interface, (5) advanced control strategies, (6) integration architectures/frameworks, (7) embedding of intelligence. Many of these technologies are mature, and they are being used in the KStorMS. The paper will describe the design, implementation, and operation of the KStorMS; and discuss further evolution to support other needs such as condition-based maintenance (CBM).

Figueroa, Fernando↗

NASA Sounding Rocket Program Educational Outreach

Educational and public outreach is a major focus area for the National Aeronautics and Space Administration (NASA). The NASA Sounding Rocket Program (NSRP) shares in the belief that NASA plays a unique and vital role in inspiring future generations to pursue careers in science, mathematics, and technology. To fulfill this vision, the NSRP engages in a variety of educator training workshops and student flight projects that provide unique and exciting hands-on rocketry and space flight experiences. Specifically, the Wallops Rocket Academy for Teachers and Students (WRATS) is a one-week tutorial laboratory experience for high school teachers to learn the basics of rocketry, as well as build an instrumented model rocket for launch and data processing. The teachers are thus armed with the knowledge and experience to subsequently inspire the students at their home institution. Additionally, the NSRP has partnered with the Colorado Space Grant Consortium (COSGC) to provide a "pipeline" of space flight opportunities to university students and professors. Participants begin by enrolling in the RockOn! Workshop, which guides fledgling rocketeers through the construction and functional testing of an instrumentation kit. This is then integrated into a sealed canister and flown on a sounding rocket payload, which is recovered for the students to retrieve and process their data post flight. The next step in the "pipeline" involves unique, user-defined RockSat-C experiments in a sealed canister that allow participants more independence in developing, constructing, and testing spaceflight hardware. These experiments are flown and recovered on the same payload as the RockOn! Workshop kits. Ultimately, the "pipeline" culminates in the development of an advanced, user-defined RockSat-X experiment that is flown on a payload which provides full exposure to the space environment (not in a sealed canister), and includes telemetry and attitude control capability. The RockOn! and RockSat-C elements of the "pipeline" have been successfully demonstrated by five annual flights thus far from Wallops Flight Facility. RockSat-X has successfully flown twice, also from Wallops. The NSRP utilizes launch vehicles comprised of military surplus rocket motors (Terrier-Improved Orion and Terrier-Improved Malemute) to execute these missions. The NASA Sounding Rocket Program is proud of its role in inspiring the "next generation of explorers" and is working to expand its reach to all regions of the United States and the international community as well.

Rosanova, G.↗