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NASA NTRSDate not supplied

Methods for Developing Successful Systems Engineers

Systems Engineering (SE) is a complex and challenging field that incorporates the knowledge of systems engineering processes, the ability to synthesize a wide-range of engineering disciplines, and the ability to lead a team of people to successfully accomplish the goals of a project. It requires hard technical skills and soft-skill leadership savvy. As a result, three main development needs are identified: 1) Knowledge of SE processes, the benefits of these processes to a project and their tailored application 2) Knowledge of a wide-range of engineering disciplines, how they interrelate in a system, and the development of sound technical judgement 3) Team leadership to direct and motivate a team of subsystem and discipline experts This paper describes the establishment of a comprehensive training and development program for Systems Engineers at NASA Ames Research Center that addresses in part each of these three areas from the perspective of the implementing manager. A variety of methods have been utilized including the establishment of a SE Community of Practice, a unique and innovative web tool, on-line videos, classroom training in NASA’s 17 Common Technical Processes, guidance on the tailored application of these processes, monthly technical talks, mentoring in both technical judgment and team leadership, and NASA’s Leadership Development Programs. While much of professional SE development must come through project experience, the approaches listed above can accelerate development. The diversity of skills required of Systems Engineering demands a multi-faceted approach to successfully train and develop this critical skill.

development↗

NASA NTRSDate not supplied

Methods for Developing Successful Systems Engineers

Systems Engineering (SE) is a complex and challenging field that incorporates the knowledge of systems engineering processes, the ability to synthesize a wide-range of engineering disciplines, and the ability to lead a team of people to successfully accomplish the goals of a project. It requires hard technical skills and soft-skill leadership savvy. As a result, three main development needs are identified: 1. Knowledge of SE processes, the benefits of these processes to a project and their tailored application 2. Knowledge of a wide-range of engineering disciplines, how they interrelate in a system, and the development of sound technical judgement 3. Team leadership to direct and motivate a team of subsystem and discipline experts This paper describes the establishment of a comprehensive training and development program for Systems Engineers at NASA Ames Research Center that addresses in part each of these three areas from the perspective of the implementing manager. A variety of methods have been utilized including the establishment of a SE Community of Practice, a unique and innovative web tool, on-line videos, classroom training in NASA’s 17 Common Technical Processes, guidance on the tailored application of these processes, monthly technical talks, mentoring in both technical judgment and team leadership, and NASA’s Leadership Development Programs. While much of professional SE development must come through project experience, the approaches listed above can accelerate development. The diversity of skills required of Systems Engineering demands a multi-faceted approach to successfully train and develop this critical skill.

development↗

DOE OSTI2023

Plasma-Coupled Flow Reactor Studies of Low-Temperature Plasma Assisted Kinetics of Methanol Blended with CO2

Ignition technologies based on low-temperature plasmas (LTP) have the potential to operate next generation engines at elevated pressures and increased dilution limits promoting higher efficiencies. From a practical standpoint, research on LTP igniters has shown to enhance combustion and ignition, improve flame stability, and extend the dilution limits of combustion. All of the aforementioned gains are complemented with higher ignition efficiencies. However, the biggest challenge with incorporating this technology into engines is the knowledge gap of how exactly plasma chemistry effects can enhance the basic combustion phenomena. This coupled with the lack of validated kinetic mechanisms for plasma-combustion chemistry is the biggest obstruction to recognize efficient ignition, especially for application relevant fuels and biofuels. In order to comprehensively evaluate the effects of LTP on an oxygenated fuel specific system, this present study examines the kinetics of methanol plasma-assisted pyrolysis and oxidation using a custom-built plasma flow reactor (PFR). Experimental regimes are also further extended to understand the effects of adding CO2 to the mixture and its consequence on reaction kinetics. The PFR is installed with a dielectric-barrier discharge (DBD) configuration to induce LTP into the fuel mixture. Non-equilibrium plasmas are generated by high-voltage pulses (nearing 20 KV) administered by a plasma pulser at high-pulse repetition rates (up to 10 kHz). In order to better understand and isolate plasma chemistry and its effect on neutral chemistry, the experiments were carried out by heavily diluting reactive mixtures in nitrogen at near isothermal conditions. This suppresses the effect of exothermic reactions on chemistry allowing stable intermediates and products to be detected and quantified using ex-situ GC/MS diagnostic methods. Experiments were carried out at 0.5 atm pressure and over a wide range of temperatures from 523 K to 1203 K. Experimental results depicted the enhancement in intermediates production as well as overall lower temperatures required for complete fuel consumption in the plasma specific cases as opposed to their pure thermal counterpart. Formation of oxygenated and nitrile compounds specific to plasma assisted pyrolysis cases illustrated the efficacy of LTP to introduce new reaction pathways accelerating fuel decomposition. Increase in reactivity at lower temperatures is sought to be an effect induced by plasma chemistry postulating the acceleration in intermediates production. The onset of thermal ignition in plasma assisted oxidation is seen 200 K earlier than thermal oxidation highlighting efficient fuel conversion to final byproducts. Enhanced collisional processes afforded by LTP is seen to perturb reaction pathways between oxygenated fuel radicals and N-atoms to alter overall chemical reactivity. New insights into kinetics are gained from this study highlighting governing plasma assisted combustion (PAC) pathways for oxygenated fuel reaction chemistry. The results from this study can be used to develop future mechanisms specific to plasma chemistry which can bridge the mechanistic knowledge gap for LTP ignition so that future engines can adopt LTPs in their design for efficient combustion.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

NASA NTRS1992

Domain and Specification Models for Software Engineering

This paper discusses our approach to representing application domain knowledge for specific software engineering tasks. Application domain knowledge is embodied in a domain model. Domain models are used to assist in the creation of specification models. Although many different specification models can be created from any particular domain model, each specification model is consistent and correct with respect to the domain model. One aspect of the system-hierarchical organization is described in detail.

Iscoe, Neil↗

NASA NTRSDate not supplied

U.S. Spacesuit Knowledge Capture – Creation, Curation, and Dissemination

The U.S. spacesuit is a special system that has intrigued and fascinated the world since Neil Armstrong set foot on the Moon in 1969. With over 50 years since that momentous achievement, NASA is planning to land the first woman and next man on the Moon in the near future. This goal begets the need to build a new spacesuit, a spacesuit created from the legacy knowledge of the Extravehicular Mobility Unit (EMU), combined with knowledge gained from technology development over the decades. As NASA transitions to its new horizon, the U.S. Spacesuit Knowledge Capture (SKC) Program is poised to help. The SKC Program’s primary function has been to capture, curate, and disseminate spacesuit-related knowledge among scientists, engineers, and technicians. The SKC Program was created in 2007 to capture knowledge primarily from spacesuit subject-matter experts (SMEs) who were retiring from NASA. These SMEs had 30 to 50 years of spacesuit knowledge. Over the years, the SKC Program has evolved and expanded its scope with a current focus on complementing the buildup of the Exploration EMU (xEMU) at the Johnson Space Center. As part of this focus, the SKC Program recently teamed with the xEMU Community of Practice (CoP) for knowledge sharing. The xEMU CoP provides a forum where early career engineers, professionals new to human spaceflight, and the xEMU community can come together regularly to seek guidance, share knowledge, meet their peers, discover resources, and ask questions. The CoP created an environment where the knowledge can be easily and routinely captured and recorded. The recorded events are archived and curated in an SKC Program library and disseminated as appropriate. This paper details the roles that the SKC Program and CoP play in the xEMU buildup, along with the navigation of the creation, curation, and dissemination processes.

Cinda Chullen↗

NASA NTRS1994

Analytical procedures for estimating structural response to acoustic fields generated by advanced launch systems, phase 2

This report supplements a previous report of the same title submitted in June, 1992. It summarizes additional analytical techniques which have been developed for predicting the response of linear and nonlinear structures to noise excitations generated by large propulsion power plants. The report is divided into nine chapters. The first two deal with incomplete knowledge of boundary conditions of engineering structures. The incomplete knowledge is characterized by a convex set, and its diagnosis is formulated as a multi-hypothesis discrete decision-making algorithm with attendant criteria of adaptive termination.

Elishakoff, Isaac↗

NASA NTRSDate not supplied

U.S. Spacesuit Knowledge Capture – Chronicling Spacesuit Design for the Future

With less than 4 years until the United States is scheduled to land the first woman and next man on the Moon, NASA is leveraging 60 years of experience to build a spacesuit to assist in the success of this and future human space exploration missions. This experience comes from the achievements of retired and employed spacesuit experts, innovations that were conceived from existing ideas and inventions, and a plethora of archived knowledge. The U.S. Spacesuit Knowledge Capture (SKC) Program’s primary function is to capture, archive, and share current and legacy spacesuit-related knowledge with scientists, engineers, and technicians. To capture valuable spacesuit-related knowledge, the program uses various methods that have included hosting and recording classroom and online courses, workshops, and vignettes, and preserving thousands of legacy spacesuit-related files. In 2019, the SKC Program added to its role when it began coordinating the electronic recording of the new spacesuits’ buildup. This new, next-generation spacesuit is named the Exploration Extravehicular Mobility Unit (xEMU) and is a compilation of many components. As each component is tested and assembled into the suit, the SKC Program is chronicling this buildup using high-speed video production and photography that includes time-lapsed images. To complement the recording of the components, the SKC Program plans to record and photograph the design verification testing. In 2020, the SKC Program was given the initiative to research and identify the custodianship of historical spacesuit equipment that resides within the Crew and Thermal Systems Division. These archives will be added to the SKC Program’s expansive archived collection of spacesuit-related knowledge that represents over 5 decades of spacesuit legacy from the Apollo era to the pursuit of Mars and beyond. This paper describes the electronic documentation of the xEMU’s buildup and identifies the SKC Program’s 2020 accomplishments.

Cinda Chullen↗

NASA NTRSDate not supplied

U.S. Spacesuit Knowledge Capture – Chronicling Spacesuit Design for the Future

Cinda Chullen↗

NASA NTRS1990

Developing a framework for qualitative engineering: Research in design and analysis of complex structural systems

The research is focused on automating the evaluation of complex structural systems, whether for the design of a new system or the analysis of an existing one, by developing new structural analysis techniques based on qualitative reasoning. The problem is to identify and better understand: (1) the requirements for the automation of design, and (2) the qualitative reasoning associated with the conceptual development of a complex system. The long-term objective is to develop an integrated design-risk assessment environment for the evaluation of complex structural systems. The scope of this short presentation is to describe the design and cognition components of the research. Design has received special attention in cognitive science because it is now identified as a problem solving activity that is different from other information processing tasks (1). Before an attempt can be made to automate design, a thorough understanding of the underlying design theory and methodology is needed, since the design process is, in many cases, multi-disciplinary, complex in size and motivation, and uses various reasoning processes involving different kinds of knowledge in ways which vary from one context to another. The objective is to unify all the various types of knowledge under one framework of cognition. This presentation focuses on the cognitive science framework that we are using to represent the knowledge aspects associated with the human mind's abstraction abilities and how we apply it to the engineering knowledge and engineering reasoning in design.

Franck, Bruno M.↗

NASA NTRS2010

From Paper to Production: An Update on NASA's Upper Stage Engine for Exploration

The NASA/industry team responsible for developing the J-2X Upper Stage Engine for the Constellation Program's Ares I and Ares V launch vehicles has made significant progress toward moving the design from paper to production during the past year. The J-2X exemplifies the Constellation goal of using proven technology and experience from more than 50 years of United States spaceflight experience and seeking where possible to employ common hardware in the Ares I crew launch vehicle and the Ares V cargo launch vehicle. The J-2X will power the Ares I upper stage to place the Orion crew vehicle in orbit. For the Ares V, the J-2X will place the Earth departure stage (EDS) and lunar lander in orbit and later re-start to send the Orion and lander to the Moon. Pratt & Whitney Rocketdyne (PWR) is under contract to develop and produce the engine, leveraging its flight-proven LH2/LOX, gas generator cycle J-2 and RS-68 engine capabilities, recent experience with the X-33 aerospike XRS-2200 engine, and development knowledge of the J-2S tap-off cycle engine. The J-2X employs a gas generator operating cycle designed to produce 294,000 pounds of thrust in primary operating mode for the Ares I and Ares V ascent phases. It also has a secondary mode, during which it operates at 80 percent thrust by altering its mixture ratio to perform the TLI burn for the Ares V lunar sortie and lunar cargo missions. The J-2X development philosophy is based on proven hardware, an aggressive development schedule, and early risk reduction. NASA Marshall Space Flight Center (MSFC) and PWR began development of the J-2X in June 2006. The government/industry team of more than 600 people within NASA and PWR successfully completed the Critical Design Review (CDR) in November 2008, following extensive risk mitigation testing. The team is working toward a first flight of the J-2X on the Orion 1 mission in 2014. This paper will discuss the J-2X development background and provide top-level information on design and testing to date. Details will be provided on overcoming challenges such as gas generator instability, turbine blade life, and nozzle extension selection and materials.

Kynard, Mike↗

NASA NTRS2011

From Paper to Production to Test: An Update on NASA's J-2X Engine for Exploration

The NASA/industry team responsible for developing the J-2X upper stage engine for the Space Launch System (SLS) Program has made significant progress toward moving beyond the design phase and into production, assembly, and test of development hardware. The J-2X engine exemplifies the SLS Program goal of using proven technology and experience from more than 50 years of United States spaceflight experience combined with modern manufacturing processes and approaches. It will power the second stage of the fully evolved SLS Program launch vehicle that will enable a return to human exploration of space beyond low earth orbit. Pratt & Whitney Rocketdyne (PWR) is under contract to develop and produce the engine, leveraging its flight-proven LH2/LOX, gas generator cycle J-2 and RS-68 engine capabilities, recent experience with the X-33 aerospike XRS-2200 engine, and development knowledge of the J-2S tap-off cycle engine. The J- 2X employs a gas generator operating cycle designed to produce 294,000 pounds of vacuum thrust in primary operating mode with its full nozzle extension. With a truncated nozzle extension suitable to support engine clustering on the stage, the nominal vacuum thrust level in primary mode is 285,000 pounds. It also has a secondary mode, during which it operates at 80 percent thrust by altering its mixture ratio. The J-2X development philosophy is based on proven hardware, an aggressive development schedule, and early risk reduction. NASA Marshall Space Flight Center (MSFC) and PWR began development of the J-2X in June 2006. The government/industry team of more than 600 people within NASA and PWR successfully completed the Critical Design Review (CDR) in November 2008, following extensive risk mitigation testing. Assembly of the first development engine was completed in May 2011 and the first engine test was conducted at the NASA Stennis Space Center (SSC), test stand A2, on 14 July 2011. Testing of the first development engine will continue through the autumn of 2011, be paused for test stand modifications to the passive diffuser, and then restart in the spring of 2012. This testing will be followed by specialized powerpack testing intended to examine the design and operating margins of the engine turbomachinery. The development plan beyond this point leads through more system-level, engine testing of several samples, analytical model validation activities, functional and performance verification, and then ultimate certification to support human spaceflight. This paper will discuss the J-2X development background, provide top-level information on design and development planning, and will explore some of the development challenges and mitigation activities pursued to date.

Kynard, Michael↗

DOE OSTI2025

System Engineers and Decisions: It?s All about Knowledge

In order to guarantee that a system meets adequate levels of reliability and availability, system performances are continuously monitored and analyzed thanks to the technological advancements driving the Industry 4.0 revolution. An Industry 4.0 approach is typically based on advanced statistical, big data mining, machine learning, and internet-of-things methods designed to detect anomalies in the behavior of system, detect the most likely failure modes, and provide indications to system engineers on when maintenance activities should be performed before system performance are deemed unacceptable (which can be generated by diagnostic and prognostic methods). However, these analyses, which are designed to automatize and increase the efficacy of the system maintenance program, require large amount of data which can come in various forms: numeric, textual, images, sounds etc. Such data constitutes the historic knowledge benchmark to track system performances and support system engineer decisions. Here we claim that data is not sufficient to support this kind of analyses when applied to systems characterized by complex architectures and behaviors. Robust system engineer decisions require the ability to understand the system operational context that lies behind the observed data elements. In this respect, system models are in fact necessary to “put data in context” and capture relationships between data elements. Industry 4.0 methods require in fact contextual knowledge as a basis upon which hypotheses can be generated and assumptions tested. In our view, for complex systems, model-based system engineering (MBSE) models can afford this contextual knowledge, as they are typically used to describe systems architecture and dynamic behaviors. System knowledge is here intended as the blending of collected data and system architecture which takes the form of a “knowledge graph”. A knowledge graph is a database which consists of a large set of nodes (in our case an entity can be either a data or an MBSE element) which are linked to each other. The types of nodes and links follow a pre-defined topology, sometimes also refers as an ontology, that is designed to fit the actual decisions that needs to be performed. We show here how a knowledge graph can be defined to support system engineer maintenance decisions and how the same graph can be built based on system MBSE models and pre-processed data from numeric (through anomaly detections and diagnostic methods) and textual elements (through technical language processing TLP).

97 - MATHEMATICS AND COMPUTING↗

NASA NTRS1989

Composite load spectra for select space propulsion structural components

The objective of the Composite Load Spectra (CLS) project is to build a knowledge based system to synthesize probabilistic loads for selected space propulsion engine components. The knowledge based system has a load expert system module and a load calculation module. The load expert system provides load information and the load calculation module generates the probabilistic load distributions. The engine loads are divided into 4 broad classes: the engine independent loads, the engine system dependent load, the component local independent loads and the component loads. These classes are defined and illustrated.

Ho, H.↗

NASA NTRSDate not supplied

Statistical Engineering

This webinar provides an overview of the International Statistical Engineering Association (ISEA), and it illustrates the practice of statistical engineering at NASA. ISEA was formed to promote the study of how successful data-based problem-solving methods are leveraged to realize innovative opportunities and solve problems sustainably. ISEA is comprised of statisticians, engineers, scientists, and other professionals that exchange ideas and experiences in the development and application of statistical engineering theories. ISEA is building the body of knowledge of the statistical engineering discipline with a particular focus on improving academic preparation for tackling complex problems. Over the past 15 years, the practice of statistical engineering has gained recognition within NASA by spurring innovation and efficiency, and it has demonstrated significant impact. Aerospace research and development benefits from an application-focused statistical engineering perspective to accelerate learning, maximize knowledge, ensure strategic resource investment, and inform data-driven decisions. The second portion of this presentation provides an overview of infusing statistical engineering at NASA through pioneering case studies in aeronautics, space exploration, and atmospheric science.

Peter A Parker↗

NASA NTRS1986

Hampton University/American Society for Engineering Education/NASA Summer Faculty Fellowship Program 1986

Since 1964, the National Aeronautics and Space Administration (NASA) has supported a program of summer faculty fellowships for engineering and science educators. In a series of collaborations between NASA research and development centers and nearby universities, engineering faculty members spend 10 or 11 weeks working with professional peers on research. The Summer Faculty Program Committee of the American Society of Engineering Education supervises the programs. Objectives: (1) To further the professional knowledge of qualified engineering and science faculty members; (2) to stimulate and exchange ideas between participants and NASA; (3) To enrich and refresh the research and teaching activities of participants' institutions; (4) to contribute to the research objectives of the NASA center. Program Description: College or university will be faculty members appointed as Research Fellows to spend 10 weeks in cooperative research and study at the NASA-Langley Research Center. The Fellow will devote approximately 90 percent of the time to a research problem and the remaining time to a study program. The study program will consist of lectures and seminars on topics of general interest or that are directly relevant to the Fellows' research project. The lecturers and seminar leaders will be distinguished scientists and engineers from NASA, education or industry.

Spencer, J. H.↗

NASA NTRS1987

NASA/American Society for Engineering Education (ASEE) Summer Faculty Fellowship Program 1987

Since 1964, NASA has supported a program of summer faculty fellowships for engineering and science educators. In a series of collaborations between NASA research and development centers and nearby universities, engineering faculty members spend 10 or 11 weeks working with professional peers on research. The Summer Faculty Program Committee of the American Society for Engineering Education supervises the programs. Objectives: (1) to further the professional knowledge of qualified engineering and science faculty members; (2) to stimulate and exchange ideas between participants and NASA; (3) to enrich and refresh the research and teaching activities of participants' institutions; (4) to contribute to the research objectives of the NASA center. Program Description: College or university faculty members were appointed as Research Fellows to spend 10 weeks in cooperative research and study at the NASA Langley Research Center. The Fellow devoted approximately 90 percent of the time to a research problem and the remaining time to a study program. The study program consisted of lectures and seminars on topics of interest or that are directly relevant to the Fellows' research topic.

Tiwari, Surendra N.↗

NASA NTRS1989

NASA/American Society for Engineering Education (ASEE) Summer Faculty Fellowship Program 1989

Since 1964, NASA has supported a program of summer faculty fellowships for engineering and science educators. The objectives are: to further the professional knowledge of qualified engineering and science faculty; to stimulate and exchange ideas between participants and NASA; to enrich and refresh the research and teachning activities of participants' institutions; and to contribute to the research objectives of the NASA center. College or university faculty members will be appointed as Research Fellows to spend 10 weeks in cooperative research and study at the NASA Langley Research Center. The Fellow will devote approximately 90 percent of the time to a research problem and the remaining time to a study program. The study program will consist of lecture and seminars on topics of interest or that are directly relevant to the Fellows' research topic.

Tiwari, Surendra N.↗

NASA NTRS1990

NASA/American Society for Engineering Education (ASEE) Summer Faculty Fellowship Program, 1990

Since 1964, NASA has supported a program of summer faculty fellowships for engineering and science educators. The objectives are to further the professional knowledge of qualified engineering and science members; to stimulate and exchange ideas between participants and NASA; to enrich and refresh the research and teaching activities of participants' institutions; and to contribute to the research objectives of the NASA center. The study program consists of lectures and seminars on topics of interest or that are directly relevant to the research topics.

Spencer, John H.↗