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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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Lunar module reaction control system engine exhaust plume evaluation tests in space environment simulation laboratories
This paper describes a system engineering approach to examining the potential for combining elements of a deep-space RF and optical communications payload, for the purpose of reducing the size, weight and power burden on the spacecraft and the mission. Figures of merit and analytical methodologies are discussed to conduct trade studies, and several potential technology integration strategies are presented. Finally, the NASA Integrated Radio and Optical Communications (iROC) project is described, which directly addresses the combined RF and optical approach.
The potential of Model Model Systems Engineering (MBSE) using the Architecture Analysis and Design Language (AADL) applied to space systems will be described. AADL modeling is applicable to real-time embedded systems- the types of systems NASA builds. A case study with the Juno mission to Jupiter showcases how this work would enable future missions to benefit from using these models throughout their life cycle from design to flight operations.
This paper describes a Modular Artificial Intelligence Inference Engine System (MAIS) support tool that would provide health and status monitoring, cognitive replanning, analysis and support of on-orbit Space Station, Spacelab experiments and systems.
A viewgraph presentation on the cost/risk analysis capability of systems engineering is shown.
The interdependence of technology development, conceptual design, and system analysis is examined in the context of an overall systems engineering set of processes. In particular, the role of technology portfolio management - from initial investment decision-making all the way through technology maturation and transfer to industry - is emphasized. Additionally, the role of state of the art assessments is considered in terms of planning and tracking progress towards the development of enhanced predictive capabilities.
The National Aeronautics and Space Administration is currently developing the Space Launch System to provide the United States with a capability to launch large Payloads into Low Earth orbit and deep space. One of the development tenets of the SLS Program is affordability. One initiative to enhance affordability is the SLS approach to requirements definition, verification and system certification. The key aspects of this initiative include: 1) Minimizing the number of requirements, 2) Elimination of explicit verification requirements, 3) Use of certified models of subsystem capability in lieu of requirements when appropriate and 4) Certification of capability beyond minimum required capability. Implementation of each aspect is described and compared to a "typical" systems engineering implementation, including a discussion of relative risk. Examples of each implementation within the SLS Program are provided.
This paper discusses the challenges and considerations in systems engineering the first planned autonomous high-level activity planner on Mars.
Volume 2, Part 1, of a seven volume report is presented. Part 1 encompasses Satellite Power Systems (SPS) systems engineering aspects and is divided into three sections. The first section presents descriptions of the various candidate concepts considered and conclusions and recommendations for a preferred concept. The second section presents a summary of results of the various trade studies and analysis conducted during the course of the study. The third section describes the Photovoltaic Satellite Based Satellite Power System (SPS) Point Design as it was defined through studies performed during the period January 1977 through March 1979.
The document summarizes the results of a faculty program in engineering systems design whose primary aim was to provide a framework for communication and collaboration between academic personnel, research engineers, and scientists in government agencies and private industry. Other objectives were to provide a useful study of a broadly based societal problem, requiring the coordinated efforts of a multidisciplinary team, and to generate experience in the development of systems design and multidisciplinary activities. The success of the program is evidenced by the resulting study of general aviation and community development, characterized by thorough scrutiny of ideas, philosophies, and academic perspectives.
We present an overview of the Systems Engineering and Assurance Modeling (SEAM) platform, a web-browser-based tool which is designed to help engineers evaluate the radiation vulnerabilities and develop an assurance approach for electronic parts in space systems. The SEAM framework consists of three interconnected modeling tools, a SysML compatible system description tool, a Goal Structuring Notation (GSN) visual argument tool, and Bayesian Net and Fault Tree extraction and export tools. The SysML and GSN sections also have a coverage check application that ensures that every radiation fault identified on the SysML side is also addressed in the assurance case in GSN. The SEAM platform works on space systems of any degree of radiation hardness but is especially helpful for assessing radiation performance in systems with commercial-off-the-shelf (COTS) electronic components.
This paper explores the separate skills and capabilities practiced until now, and the powerful coupling to be achieved, practically and effectively, in implementing a space mission, from inception (pre-phase A) to the end of Operations (phase E). The use of risk assessment techniques in balancing cost risk against performance risk, and the application of the systems engineering team in these trades, is the key to achieving this new implementation paradigm.
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A mean line pump flow modeling method has been developed to provide a fast capability for modeling turbopumps of rocket engines. Based on this method, a mean line pump flow code PUMPA has been written that can predict the performance of pumps at off-design operating conditions, given the loss of the diffusion system at the design point. The pump code can model axial flow inducers, mixed-flow and centrifugal pumps. The code can model multistage pumps in series. The code features rapid input setup and computer run time, and is an effective analysis and conceptual design tool. The map generation capability of the code provides the map information needed for interfacing with a rocket engine system modeling code. The off-design and multistage modeling capabilities of the code permit parametric design space exploration of candidate pump configurations and provide pump performance data for engine system evaluation. The PUMPA code has been integrated with the Numerical Propulsion System Simulation (NPSS) code and an expander rocket engine system has been simulated. The mean line pump flow code runs as an integral part of the NPSS rocket engine system simulation and provides key pump performance information directly to the system model at all operating conditions.
An account is given of the development status and achievements to date of the U.S. Army Propulsion Directorate's Small Turbine Engine Research (STER) programs, which are experimental investigations of the physics of entire engine systems from the viewpoints of component interactions and/or system dynamics. STER efforts are oriented toward the evaluation of complete turboshaft engine advanced concepts and are conducted at the ECRL-2 indoor, sea-level engine test facility. Attention is given to the results obtained by STER experiments concerned with IR-suppressing engine exhausts, a ceramic turbine-blade shroud, an active shaft-vibration control system, and a ceramic-matrix combustor liner.
An overview of the CASE/A-ECLSS series modeling package is presented. CASE/A is an analytical tool that has supplied engineering productivity accomplishments during ECLSS design activities. A components verification program was performed to assure component modeling validity based on test data from the Phase II comparative test program completed at the Marshall Space Flight Center. An integrated plotting feature has been added to the program which allows the operator to analyze on-screen data trends or get hard copy plots from within the CASE/A operating environment. New command features in the areas of schematic, output, and model management, and component data editing have been incorporated to enhance the engineer's productivity during a modeling program.
Space emergency reentry vehicle - NASA Faculty Systems Engineering Institute Conference, University of Houston, June-August 1967
NASA is working toward the first launch of the Space Launch System, a new, unmatched capability for deep space exploration with launch readiness planned for 2019. Since program start in 2011, SLS has passed several major formal design milestones, and every major element of the vehicle has produced test and flight hardware. The SLS approach to systems engineering has been key to the program's success. Key aspects of the SLS SE&I approach include: 1) minimizing the number of requirements, 2) elimination of explicit verification requirements, 3) use of certified models of subsystem capability in lieu of requirements when appropriate and 4) certification of capability beyond minimum required capability.