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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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Viewgraphs on Enabler 1 and 2 engine system design modeling and comparisons are presented. The objective of this research was to define a near-term solid-core nuclear thermal propulsion (NTP) engine system scaling database. A unified set of performance, weight, and size scaling data are identified and documented. Results should be useful to meet initial mission and concept design study requirements.
A system engineering and economic analysis was conducted to establish typical reference baselines for the photovoltaic, solar thermal, and nuclear satellite power systems. Tentative conclusions indicate that feasibility and economic viability are characteristic of the Satellite Power System. Anticipated technology related to manufacturing, construction, and maintenance operations is described. Fuel consumption, environmental effects, and orbital transfer are investigated. Space shuttles, local space transportation, and the heavy lift launch vehicle required are also discussed.
Developing and implementing a plan for a NASA space mission can be a complicated process. The needs, goals, and objectives of any proposed mission or technology must be assessed early in the Project Life Cycle. The key to successful development of a space mission or flight project is the inclusion of systems engineering in early project formulation, namely during Pre-phase A, Phase A, and Phase B of the NASA Project Life Cycle. When a space mission or new technology is in pre-development, or "pre-Formulation", feasibility must be determined based on cost, schedule, and risk. Inclusion of system engineering during project formulation is key because in addition to assessing feasibility, design concepts are developed and alternatives to design concepts are evaluated. Lack of systems engineering involvement early in the project formulation can result in increased risks later in the implementation and operations phases of the project. One proven method for effective systems engineering practice during the pre-Formulation Phase is the use of a mission conceptual design or technology development laboratory, such as the Mission Design Lab (MDL) at NASA's Goddard Space Flight Center (GSFC). This paper will review the engineering process practiced routinely in the MDL for successful mission or project development during the pre-Formulation Phase.
Automatic failure-cause diagnosis is a key element in autonomous operation of space power systems such as Space Station's. A rule-based diagnostic system has been developed for determining the cause of degraded performance. The knowledge required for such diagnosis is elicited from the system engineering process by using traditional failure analysis techniques. Symptoms, failures, causes, and detector information are represented with structured data; and diagnostic procedural knowledge is represented with rules. Detected symptoms instantiate failure modes and possible causes consistent with currently held beliefs about the likelihood of the cause. A diagnosis concludes with an explanation of the observed symptoms in terms of a chain of possible causes and subcauses.
Operations support as considered here is the infrastructure of people, procedures, facilities and systems that provide NASA with the capability to conduct space missions. This infrastructure involves most of the Centers but is concentrated principally at the Johnson Space Center, the Kennedy Space Center, the Goddard Space Flight Center, and the Jet Propulsion Laboratory. It includes mission training and planning, launch and recovery, mission control, tracking, communications, data retrieval and data processing.
When asked about his processes in designing a new airplane, Burt Rutan responded: ...there is always a performance requirement. So I start with the basic physics of an airplane that can get those requirements, and that pretty much sizes an airplane... Then I look at the functionality... And then I try a lot of different configurations to meet that, and then justify one at a time, throwing them out... Typically I'll have several different configurations... But I like to experiment, certainly. I like to see if there are other ways to provide the utility. This kind of thinking engineering as a total systems engineering approach is what is being instilled in all engineers at the NASA Dryden Flight Research Center.
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The X-57 Maxwell is an electric aircraft based on a 4-passenger, twin engine Tecnam P2006T General Aviation aircraft. The X-57 project originally envisioned a straightforward integration of commercial-off-the-shelf hardware components and software into a novel configuration to demonstrate the aerodynamic and performance benefits of Distributed Electric Propulsion (DEP). The project was initially started with a high-risk venture capitalist approach under NASA’s Convergent Aeronautics Solutions (CAS) project, which led to an initial philosophy of Project Management “light” (which was then interpreted as Systems Engineering (SE) “light”). As the project matured, it was forced to transition to one with increasing SE-rigor as the project scope changed, hardware and software deficiencies were found, and the team realized the magnitude of the technical and integration challenges. In hindsight, these technical challenges came in part from an overly optimistic technology readiness assessment (TRA) at the beginning of the project, which resulted in the project assuming that little to no subsystem development would be required. The project’s approach to systems engineering evolved throughout three separate informal phases of the project as it underwent two key transitions as a result of the team wrestling with the technical challenges and resultant changing project scope. This paper discusses the assumptions, approaches, and challenges encountered from a Systems Engineering standpoint in each of the three informal phases of the X-57 project. This paper also provides recommendations on how future projects can apply Systems Engineering best practices upfront along with a realistic TRA to aid projects that find themselves with similar challenges.
While the causes of failures in complex engineered systems are often clear in hindsight, it can be challenging to predict failures proactively during the design of novel engineered products or systems. Identifying patterns can be useful for capturing common characteristics that may lead to failure. In this paper, we present a methodology for identifying patterns of failure from NASA’s publicly available Lessons Learned Information System (LLIS). We apply an ontology development and clustering approach to identify representative patterns leading to failures in historical lessons learned. A joint inductive-deductive approach reveals the key themes in lessons that lead to failure, which are formalized and recorded as an ontology of complex systems failure causes. Documents from the LLIS are manually tagged with relevant characteristics from the ontology. From the tagged set, clustering is used to capture co-occurring sets of characteristics that lead to failure. The primary contribution of this work is a method for extracting a set of generic failure patterns in complex engineered systems and characteristics for these patterns that can be identified at design time, knowledge of which can be used to plan mitigation strategies.
Lightweight flight prototype mercury ion engine system development and testing
Human exploration missions to beyond low Earth orbit destinations such as Mars will require more autonomous capability compared to current low Earth orbit operations. For the medical system, lack of consumable resupply, evacuation opportunities, and real-time ground support are key drivers toward greater autonomy. Recognition of the limited mission and vehicle resources available to carry out exploration missions motivates the Exploration Medical Capability (ExMC) Element's approach to enabling the necessary autonomy. The Element's work must integrate with the overall exploration mission and vehicle design efforts to successfully provide exploration medical capabilities. ExMC is applying systems engineering principles and practices to accomplish its integrative goals. This talk will briefly introduce the discipline of systems engineering and key points in its application to exploration medical capability development. It will elucidate technical medical system needs to be met by the systems engineering work, and the structured and integrative science and engineering approach to satisfying those needs, including the development of shared mental and qualitative models within and external to the human health and performance community. These efforts are underway to ensure relevancy to exploration system maturation and to establish medical system development that is collaborative with vehicle and mission design and engineering efforts.
Lightweight flight prototype mercury ion engine system development and testing
One embodiment of the present invention is a unique gas turbine engine system. Another embodiment is a unique exhaust nozzle system for a gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engine systems and exhaust nozzle systems for gas turbine engines. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.
An overview of Mobile Satellite System (MSS) propagation measurements and modeling is given, including a summary of results. The simple models presented should be of some use to systems engineers. A complete summary of propagation experiments with literature references is included.
There are many tools that systems engineers use in today's space programs. In my time in the Commercial Crew Program I sought to improve one of the vital tools for the verification and validation team. This was my main project but only a small part of what I have done in the department. I have also had the chance to learn from the best and see actual hardware, this real world experience will help me be a better aerospace engineer when I enter the workforce. I look forward to seeing the Commercial Crew Program progress to launch.
This charter establishes the International Space Station Program (ISSP) Mobile Servicing System (MSS) Systems Engineering Working Group (SEWG). The MSS SEWG is established to provide a mechanism for Systems Engineering for the end-to-end MSS function. The MSS end-to-end function includes the Space Station Remote Manipulator System (SSRMS), the Mobile Remote Servicer (MRS) Base System (MBS), Robotic Work Station (RWS), Special Purpose Dexterous Manipulator (SPDM), Video Signal Converters (VSC), and Operations Control Software (OCS), the Mobile Transporter (MT), and by interfaces between and among these elements, and United States On-Orbit Segment (USOS) distributed systems, and other International Space Station Elements and Payloads, (including the Power Data Grapple Fixtures (PDGFs), MSS Capture Attach System (MCAS) and the Mobile Transporter Capture Latch (MTCL)). This end-to-end function will be supported by the ISS and MSS ground segment facilities. This charter defines the scope and limits of the program authority and document control that is delegated to the SEWG and it also identifies the panel core membership and specific operating policies.