3,973 research outputs found

    Developing Methods of Obtaining Quality Failure Information from Complex Systems

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    The complexity in most engineering systems is constantly growing due to ever-increasing technological advancements. This result in a corresponding need for methods that adequately account for the reliability of such systems based on failure information from components that make up these systems. This dissertation presents an approach to validating qualitative function failure results from model abstraction details. The impact of the level of detail available to a system designer during conceptual stages of design is considered for failure space exploration in a complex system. Specifically, the study develops an efficient approach towards detailed function and behavior modeling required for complex system analyses. In addition, a comprehensive research and documentation of existing function failure analysis methodologies is also synthesized into identified structural groupings. Using simulations, known governing equations are evaluated for components and system models to study responses to faults by accounting for detailed failure scenarios, component behaviors, fault propagation paths, and overall system performance. The components were simulated at nominal states and varying degrees of fault representing actual modes of operation. Information on product design and provisions on expected working conditions of components were used in the simulations to address normally overlooked areas during installation. The results of system model simulations were investigated using clustering analysis to develop an efficient grouping method and measure of confidence for the obtained results. The intellectual merit of this work is the use of a simulation based approach in studying how generated failure scenarios reveal component fault interactions leading to a better understanding of fault propagation within design models. The information from using varying fidelity models for system analysis help in identifying models that are sufficient enough at the conceptual design stages to highlight potential faults. This will reduce resources such as cost, manpower and time spent during system design. A broader impact of the project is to help design engineers identifying critical components, quantifying risks associated with using particular components in their prototypes early in the design process and help improving fault tolerant system designs. This research looks to eventually establishing a baseline for validating and comparing theories of complex systems analysis

    A Total Systems analysis Method for the Conceptual design of Spacecraft: An application to Remote Sensing Imager Systems

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    Increased emphasis is being placed on improving the performance of space projects, within tighter budgets and shorter development times. This has led to a need for more efficient space system design methods. The research described here represents an effort to develop and evaluate such a method. Systems engineering and concurrent engineering together provide the theoretical foundation for the method. The method, derived from both this theoretical foundation and ideas from experts in the space industry, emphasizes a total systems analysis approach, taking into account given mission requirements, and the mathematical modeling of interactions between system variables and between subsystems. The emphasis makes it possible to apply the method for effectively sizing and configuring the full space project, its subsystems, and its variables. Size and configuration issues are especially important in the early conceptual design stages. The focus of this research and the developed method was, therefore, put on facilitating the design decisions taking place during those design stages. Mass, as a proxy for cost, was selected as the evaluation and optimization criterion. To make the method practical, LabVIEW was selected for developing the total systems analysis model. LabVIEW is a graphical programming language that is easy to learn, program, modify, and run; and, it has a good user interface. These characteristics make it well suited for rapid model development and for performing the large number of analysis runs required in the early conceptual design stages. The method was demonstrated for a V/IR (Visual/Infrared) space based Earth observation system. The mathematical model describing the interactions in this system was developed in close cooperation with subsystem specialists, primarily at NASA Langley Research Center, making it as realistic as possible. The model includes some 300 variables and 130 equations, and uses 1.7 MB of code. The demonstration, focusing on size and configuration issues, showed how the method and model could be used for better understanding of model dynamics, for evaluating alternative technologies, for detecting technology limits, for performing inter-subsystem analyses, and for suggesting new technology developments. It is hoped that this research will encourage engineers and project managers in the space sector to apply the developed design method to other types of space projects

    Collaborative Networks, Decision Systems, Web Applications and Services for Supporting Engineering and Production Management

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    This book focused on fundamental and applied research on collaborative and intelligent networks and decision systems and services for supporting engineering and production management, along with other kinds of problems and services. The development and application of innovative collaborative approaches and systems are of primer importance currently, in Industry 4.0. Special attention is given to flexible and cyber-physical systems, and advanced design, manufacturing and management, based on artificial intelligence approaches and practices, among others, including social systems and services

    An Assessment of Integrated Flywheel System Technology

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    The current state of the technology in flywheel storage systems and ancillary components, the technology in light of future requirements, and technology development needs to rectify these shortfalls were identified. Technology efforts conducted in Europe and in the United States were reviewed. Results of developments in composite material rotors, magnetic suspension systems, motor/generators and electronics, and system dynamics and control were presented. The technology issues for the various disciplines and technology enhancement scenarios are discussed. A summary of the workshop, and conclusions and recommendations are presented

    Space resources. Volume 2: Energy, power, and transport

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    This volume of the Space Resources report covers a number of technical and policy issues concerning the energy and power to carry out advanced space missions and the means of transportation to get to the sites of those missions. Discussed in the first half of this volume are the technologies which might be used to provide power and a variety of ways to convert power from one form to another, store it, move it wherever it is needed, and use it. In the second half of this volume, various kinds of transportation, including both interplanetary and surface systems, are discussed

    Stealth Assessment

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    An approach to performance-based assessments that embeds assessments in digital games in order to measure how students are progressing toward targeted goals.To succeed in today's interconnected and complex world, workers need to be able to think systemically, creatively, and critically. Equipping K-16 students with these twenty-first-century competencies requires new thinking not only about what should be taught in school but also about how to develop valid assessments to measure and support these competencies. In Stealth Assessment, Valerie Shute and Matthew Ventura investigate an approach that embeds performance-based assessments in digital games. They argue that using well-designed games as vehicles to assess and support learning will help combat students' growing disengagement from school, provide dynamic and ongoing measures of learning processes and outcomes, and offer students opportunities to apply such complex competencies as creativity, problem solving, persistence, and collaboration. Embedding assessments within games provides a way to monitor players' progress toward targeted competencies and to use that information to support learning.Shute and Ventura discuss problems with such traditional assessment methods as multiple-choice questions, review evidence relating to digital games and learning, and illustrate the stealth-assessment approach with a set of assessments they are developing and embedding in the digital game Newton's Playground. These stealth assessments are intended to measure levels of creativity, persistence, and conceptual understanding of Newtonian physics during game play. Finally, they consider future research directions related to stealth assessment in education

    Automation and robotics human performance

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    The scope of this report is limited to the following: (1) assessing the feasibility of the assumptions for crew productivity during the intra-vehicular activities and extra-vehicular activities; (2) estimating the appropriate level of automation and robotics to accomplish balanced man-machine, cost-effective operations in space; (3) identifying areas where conceptually different approaches to the use of people and machines can leverage the benefits of the scenarios; and (4) recommending modifications to scenarios or developing new scenarios that will improve the expected benefits. The FY89 special assessments are grouped into the five categories shown in the report. The high level system analyses for Automation & Robotics (A&R) and Human Performance (HP) were performed under the Case Studies Technology Assessment category, whereas the detailed analyses for the critical systems and high leverage development areas were performed under the appropriate operations categories (In-Space Vehicle Operations or Planetary Surface Operations). The analysis activities planned for the Science Operations technology areas were deferred to FY90 studies. The remaining activities such as analytic tool development, graphics/video demonstrations and intelligent communicating systems software architecture were performed under the Simulation & Validations category

    Conference on Spacecraft Reconnaissance of Asteroid and Comet Interiors : January 8-10, 2015, Tempe, Arizona

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    The goal of AstroRecon is to identify and evaluate the best technologies for spacecraft robotic reconnaissance of comets, asteroids, and small moons--paving the way for advanced science missions, exploration, sample return, in situ resource utilization, hazard mitigation, and human visitation.Shell GameChanger, ASU NewSpace, The Johns Hopkins University Applied Physics Laboratoryinstitutional support Arizona State University, Lunar and Planetary Institute, National Aeronautics and Space Administration, Universities Space Research Association Arizona State University's Students for the Exploration and Development of Space ; sponsors Shell GameChanger, ASU NewSpace, The Johns Hopkins University Applied Physics Laboratory ; conveners Erik Asphaug Arizona State University, Tempe, Jekan Thangavelautham Arizona State University, Tempe ; program committee Erik Asphaug (Co-chair Science) Arizona State University, Tempe [and 6 others].PARTIAL CONTENTS: Human Exploration / P. A. Abell and A. S. Rivkin--Comet Radar Explorer / E. Asphaug--Development of Communication Technologies and Architectural Concepts for Interplanetary Small Satellite Communications / A. B. Babuscia and K. C. Cheung--Numerical Simulations of Spacecraft-Regolith Interactions on Asteroids / R.-L. Ballouz, D. C. Richardson, P. Michel, and S. R. Schwartz--Kuiper: A Discover, Class Observatory for Outer Solar System Giant Planets, Satellites, and Small Bodies / J. F. Bell, N. M. Schneider, M. E. Brown, J. T. Clarke, B. T. Greenhagen, R. M.C. Lopes, A. R. Hendrix, and M. H. Wong--Landing on Small Bodies: From the Rosetta Lander to MASCOT and Beyond / J. Biele, S. Ulamec, P.-W. Bousquet, P. Gaudon, K. Geurts, T.-M. Ho, C. Krause, R. Willnecker, and M. Deleuze--High-Resolution Bistatic Radar Imaging in Support of Asteroid and Comet Spacecraft Missions / M. W. Busch, L. A. M. Benner, M. A. Slade, L. Teitelbaum, M. Brozovic, M. C. Nolan, P. A. Taylor, F. Ghigo, and J. Ford--Asteroid Comet and Surface Gravimetric Surveying can Reveal Interior Structural Details / K. A. Carroll

    Advances in Spacecraft Systems and Orbit Determination

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    "Advances in Spacecraft Systems and Orbit Determinations", discusses the development of new technologies and the limitations of the present technology, used for interplanetary missions. Various experts have contributed to develop the bridge between present limitations and technology growth to overcome the limitations. Key features of this book inform us about the orbit determination techniques based on a smooth research based on astrophysics. The book also provides a detailed overview on Spacecraft Systems including reliability of low-cost AOCS, sliding mode controlling and a new view on attitude controller design based on sliding mode, with thrusters. It also provides a technological roadmap for HVAC optimization. The book also gives an excellent overview of resolving the difficulties for interplanetary missions with the comparison of present technologies and new advancements. Overall, this will be very much interesting book to explore the roadmap of technological growth in spacecraft systems
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