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AIAA Guidance, Navigation, and control Conference 2015, MGNC 2015 - Held at the AIAA SciTech Forum 2015

作者： Trawny, Nikolas Huertas, Andres Luna, Michael E. Villalpando, Carlos Y. Martin, Keith E. Carson, John M. Johnson, Andrew E. Restrepo, Carolina Roback, Vincent E. GN&C Hardware and Testbed Development Group Jet Propulsion Laboratory California Institute of Technology PasadenaCA91109 United States Maritime & Aerial Perception Systems Group Jet Propulsion Laboratory California Institute of Technology PasadenaCA91109 United States Guidance & Control Operations Group Jet Propulsion Laboratory California Institute of Technology PasadenaCA91109 United States Advanced Computer Systems & Technologies Group Jet Propulsion Laboratory California Institute of Technology PasadenaCA91109 United States Simulation & Support Equipment Group Jet Propulsion Laboratory California Institute of Technology PasadenaCA91109 United States Jet Propulsion Laboratory California Institute of Technology PasadenaCA91109 United States Integrated GN&C Analysis Branch NASA Johnson Space Center HoustonTX77058 United States Remote Sensing Flight Systems Branch NASA Langley Research Center HamptonVA23681 United States

ISBN: (纸本)9781510801097

The Hazard Detection System (HDS) is a component of the ALHAT (Autonomous Landing and Hazard Avoidance technology) sensor suite, which together provide a lander Guidance, Navigation and control (GN&C) system with the relevant measurements necessary to enable safe precision landing under any lighting conditions. The HDS consists of a stand-alone compute element (CE), an Inertial Measurement Unit (IMU), and a gimbaled ash LIDAR sensor that are used, in real-time, to generate a Digital Elevation Map (DEM) of the landing terrain, detect candidate safe landing sites for the vehicle through Hazard Detection (HD), and generate hazard-relative navigation (HRN) measurements used for safe precision landing. Following an extensive ground and helicopter test campaign, ALHAT was integrated onto the Morpheus rocket-powered terrestrial test vehicle in March 2014. Morpheus and ALHAT then performed five successful free flights at the simulated lunar hazard field constructed at the Shuttle Landing Facility (SLF) at Kennedy Space center, for the first time testing the full system on a lunar-like approach geometry in a relevant dynamic environment. During these flights, the HDS successfully generated DEMs, correctly identified safe landing sites and provided HRN measurements to the vehicle, marking the first autonomous landing of a NASA rocket-powered vehicle in hazardous terrain. This paper provides a brief overview of the HDS architecture and describes its in-flight performance. © 2015, E-flow American Institute of Aeronautics and Astronautics (AIAA). All rights reserved.

关键词： Hazards

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Vision tracking system for narrow butt seams with CO2 gas shielded arc welding

Vision tracking system for narrow butt seams with CO2 gas sh...

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International Conference on Autonomous Robots and Agents, ICARA

作者： De Xu Zhiguo Yan Zaojun Fang Min Tan Institute of Automation Chinese Academy of Sciences Beijing China Intelligent Equipment and Control Technology Institute Dongfang Electric Corporation Research and Development Center Chengdu China

An image-based visual system is proposed for narrow butt welding seam tracking in container manufacturing. A smart camera is used as the sensor to measure the welding seam. The feature extraction algorithm is designed based on the smart camera, which is used to compute the error between the welding torch and the welding seam. The reference feature is determined with many frames of images based on their statistical property. The current estimated feature is checked based on the reference feature. The abnormal features caused by strong noises such as welding arc light, splashes and fog are rejected. The normal features are used for welding seam tracking. A compact vision system for tracking seams is presented, which employs a programmable controller to control a stepper motor to eliminate the error detected by the smart camera. Experiments are well conducted to verify the effectiveness of the proposed system and method.

关键词： Welding Feature extraction Smart cameras Visualization Containers Cameras

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Abstracts from the 6th International Conference on the Engineering of Sport, 10-14 July 2006, Olympic Hall, Munich, Germany Abstracts

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SPORTS ENGINEERING 2006年第2期9卷 107-127页

作者： [Anonymous] University of Massachusetts Lowell USA Science & Mathematics Department Kettering University Flint USA University of Illinois USA Western Michigan University USA Washington State University USA Casecade Engine USA Kanazawa University Japan Sumitomo Light Metal Japan Massachusetts Institute of Technology USA Nanyang Technological University Bioengineering Singapore University of Vienna Anthropology Austria Department of Mechanical Engineering University of Bath UK INSA Lyon France PETZL France Sports Materials Research Group University of Birmingham UK Laboratoire de Modélisation des Activités Sportives Bourget du Lac France Technical University Kaiserslautern Germany Department of Engineering Mechanics United States Air Force Academy Colorado Springs USA SRAM Corporation Colorado Springs USA Sports Engineering Research Group University of Sheffield UK Sports Engineering CSES Sheffield Hallam University USA Sports Engineering CSES Sheffield Hallam University UK Technische Universität München Germany Rush University Medical Center Chicago USA Faculty of Sports Science Department of Sport Equipment & Materials TU München Germany RMIT University Australia Institute of Health and Sports Sciences University of Tsukuba Ibaraki Japan Machine and Control Department Polytechnic University Kanagawa Japan SRI Sports Ltd. Hyogo Japan SRI Research and Development Ltd. Hyogo Japan Mizuno Corporation Osaka Japan Fukuoka Institute of Technology Fukuoka Japan University of Limerick Éire Graduate School of Engineering Hokkaido University Japan Faculty of Engineering Kitami Institute of Technology Japan University of Calgary Canada TaylorMade-adidas Golf Company USA Davis Mechanical Engineering University of California USA Davis Mechanical & Aeronautical Engineering University of California USA University of Wales Institute Cardiff Cardiff School of Sport UWIC Cardiff Cardiff School of Sport UWIC Wales Loughborough University UK Cranfield University UK Cr

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Sulfidation-resistant nickel-base superalloy for FCC gas expander turbine

Sulfidation-resistant nickel-base superalloy for FCC gas exp...

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Corrosion 2000

作者： Yakuwa, Hiroshi Miyasaka, Matsuho Go, Tetsu Nakahama, Shuhei Kawasaki, Masamichi Fang, Cheng Narita, Toshio Technology Development Center Ebara Research Company 2-1 Honfujisawa-4 Fujisawa251-8502 Japan Materials and Joining Engineering Office Machinery and Equipment Group Ebara Corporation 20-1 Nakasode Sodegaura299-0296 Japan Project Coordination Office Machinery and Equipment Group Ebara Corporation Nissay Aroma Square 5-37-1 Kamata Ohta-ku144-8721 Japan Research Group Interface Control Engineering Graduate School of Engineering Hokkaido University Kita-13 Nishi-8 Kita-ku Sapporo060-8628 Japan

A nickel-base superalloy that has excellent sulfidation resistance, high-temperature tensile properties and hot workability was developed as a material for the rotors of FCC gas expander turbines. The effect of Mo, Ti and/or Al additions on the sulfidation behavior of a Ni-20Cr-13.5Co alloy was investigated in H2-H2S mixtures at 873 K (600 C/1112 F). It was found that increasing the Al content in the alloy could improve the sulfidation resistance of AISI 685 (UNS N07001). Six kinds of forged alloy, in which the Al content was increased while Ti content was decreased, were manufactured. Sulfidation tests and high-temperature tensile tests of those alloys indicated that the 1.5Ti-3.0Al alloy has about twice the sulfidation resistance and almost equivalent tensile properties to those of AISI 685. Therefore, the 1.5Ti-3.0Al alloy was selected as the most suitable alloy for FCC gas expander rotors. A 1400 mm diameter-expander rotor disk of this developed alloy was manufactured. Test specimens cut out of the disk rim showed that the disk had equivalent tensile properties both at room and elevated temperatures, and the same creep rupture strength as that of AISI 685. © 2000 by NACE International.

关键词： Superalloys

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A UHF-ECR plasma etcher for insulation films

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Hitachi Review 2000年第4期49卷 211-215页

作者： Kawahara, Hironobu Tokunaga, Takafumi Kojima, Masayuki Yokogawa, Ken'etsu Hitachi Ltd. Semiconduct. Mfg. Equipment Group Semiconduct. Equip. Product Division Process Development Department Device Development Center Hitachi Ltd. Production Control Department Semiconductor Group Hitachi Ltd. Hitachi Ltd. Adv. Technology Research Department Central Research Laboratory

In the rapid evolution of VLSI technology toward smaller geometries and increased levels of chip integration, minimum features of 0.18 μm are already being mass produced, and feature sizes of 0.13 μm are being developed. At the same time, 300-mm fab lines are being built, and this is driving a demand for new etching technologies that support smaller tolerances and larger wafer sizes. Insulation layer etching demands good selectivity between mask and substrate and high-aspect vertical processing to deal with increasing aspect ratios and thinner mask thicknesses that go along with shrinking geometries and increasing integration levels. Meanwhile, damascene processes (electroplating for chip interconnects) using a combination of low-κ (low dielectric constant) insulation materials and Cu interconnects are being investigated, and etchers capable of processing these structures will be in great demand. To address these issues, we have developed an insulation layer etcher that uses UHF-ECR (ultra high frequency electron cyclotron resonance) plasma. The unique advantages of this approach are that it enables good control over CF 2/F radicals, an important etchant for selectivity and high-aspect openings, and good control over the ratio of ions to CF2, which is important in achieving vertical profiles. This etcher is capable of (1) producing stable and uniform medium-to-high density plasmas over a large area at low-to-medium pressures using UHF wave (450 MHz) ECR, and (2) increasing the doubled-near-surface effect* and good radical ratio control through control over the UHF wave flat antenna and antenna bias. Taken together, these capabilities amount to a powerful plasma process tool able to process fine features below 0.13 μm.

关键词： Dielectric films

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Probabilistic risk analysis of diesel power generators onboard ships

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NAVAL ENGINEERS JOURNAL 1999年第3期111卷 35-58页

作者： Ayyub, BM Karaszewski, ZJ Wade, M Bilal M. Ayyub.:is a Professor of Civil Enginnering and the Director of the Center for Technology and Systems Management at the University of Maryland (College Park). He is also a researcher and consultant in the areas of structural engineering inspection methods and practices reliability and risk analysis. He completed his B.S. degree in civil engineering in 1980 and completed both the M.S. (1981) and Ph.D. (1983) in civil engineering at the Georgia Institute of Technology. Dr. Ayyub has an extensive background in uncertainty modeling and marine structural reliability marine structures uncertainty modeling and anaylsis and mathematical medeling using the theories of probability statistics and fuzzy sets. He has completed several research projects that were funded by the NSF USCG USN the USACE ASME and several engineering companies. Dr. Ayyub served the engineering community in various capacities through societies that include ASNE ASCE ASME SNAME IEEECS and NAFIPS. He is the authour and co-author of about 250 publications in journals and conference proceedings and reports. His publications include edited books textbooks and book chapters. Dr. Ayyub is the only double recipient of the ASNE “Jimmie” Hamilton Award for the best papers in the Naval Engineers Journal in 1985 and 1992. Also he received the ASCE “Outstanding Research Oriented Paper” in the Journal of Walter L. Huber Research Prize in 1997 and the K.S. Fu Award of NAFIPS in 1995. He is a registered Professional Engineer (PE) with the State of Maryland. Zbigniew J. Karaszewski:is the Associate Director of the University of Maryland's Center for Technology and Systems Management and technical director of the Center for Maritime Leadership. He is a Systems Engineering and Management Consultant specializing in life cycle system support business systems auditing and risk management and loss prevention. Mr. Karasezewski has 30 years of experience in the field of systems performance analysis and management as a practitioner and teacher

In this paper, a methodology and guidelines for applying risk methods in design and operation of maritime systems were developed and demonstrated using a case study of marine diesel generators. The methodology consists of several modules that include system definition based on functional and performance requirements, definition of dependencies among subsystems, data collection and reduction, reliability and risk analyses, and results reduction for use in decision analysis. The methodology was used to assess and analyze typical service diesel generators found onboard ships. The analysis included the generation of cut sets for the overall reliability of the system. The most likely failure scenarios were determined by demonstration as the failure of fuel supply components. The results are consistent with previous findings of the U.S. Coast Guard.

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ASYNCHRONOUS TRANSFER MODE (ATM) OPERATION VIA SATELLITE - ISSUES, CHALLENGES AND RESOLUTIONS

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第3期12卷 211-222页

作者： CHITRE, DM GOKHALE, DS HENDERSON, T LUNSFORD, JL MATHEWS, N COMSAT Laboratories 22300 Comsat Drive Clarksburg MD 20871 USA. Received his B.Sc. from the University of Bombay India an M.A. in mathematics from the University of Cambridge U.K. and a Ph.D. in physics from the University of Maryland. He is currently an Associate Executive Director of the Network Technology Division at COMSAT Laboratories. He has been involved in research and development activities in ISDN VSAT networks data communications and network systems and architectures. Prior to his current positions Dr. Chitre was a Principal Scientist in the Network Technology Division at COMSAT Laboratories. Dr. Chitre joined COMSAT Laboratories in 1980. He has made major contributions to the analysis and architecture of data communication ISDN and BISDN via satellite. Dr. Chitre directs and participates in the international and national standards activities in ISDN BISDN and data communication as they apply to satellite communication. He was Chairman of the Working Group on Protocols and Network Timing Function of the CCIR/CCITT Joint Ad Hoc Group on ISDN-Satellite Matters during 1990–1992. Currently he is the Chairman of the Working Group on New Technologies in the ITU Intersector Coordinating Group (ICG) on Satellite Matters. Dr. Chitre was a programme manager during 1990 and 1991 on a contract from INTELSAT on systems studies on satellite communications systems architectures for ISDN and broadband ISDN systems. Currently he is the technical manager of the DoD Contract on ATM via satellite demonstration and the programme manager for the INTELSAT contract on analysis and top-level specification of INTELSAT ISDN subnetworks and SDH compatible transport network. Department manager for ISDN/Data Communications in the Network Technology Division of COMSAT Laboratories. His responsibilities include managing the implementation of next generation telecommunication systems for fixed and mobile satellite systems. Current projects include the development of a high data rate gateway switch that provides for the

Key issues regarding the operation of the broadband integrated services digital network (BISDN) via satellite are presented herein. The specific issues, challenges, and their resolutions are detailed. In particular, the impact of error characteristics and propagation delay on the operation of BISDN via satellite is discussed. Solutions are presented for removing adverse effects and providing high-quality service to users of BISDN via satellite.

关键词： ATM BISDN

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ACQUISITION REFORM AND BEST PRODUCT PROCUREMENT - AN ENGINEERING VIEW

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NAVAL ENGINEERS JOURNAL 1994年第6期106卷 41-57页

作者： FISHER, DA SKOLNICK, A He has been involved with several weapon system developments. Among these were the Trident II fire control and navigation systems the BSY-I Anti-Submarine Warfare System and the Navy standard computers (UYK44 and EMSP). He served as manager of the Digital Circuits Engineering Branch and was then appointed as manager of the Automatic Test Equipment (ATE) Technology Division. As manager of the ATE Technology Division he was responsible for the SP-23 Fire Control System Support Project the SP-24 Navigation Project and the Fleet Progressive Maintenance Program (2M/ATE). This Division was responsible for selection and application of electronic product technology and for developing fleet test and repair techniques. He holds a B.S. in Electrical Engineering from the University of Evansville and is currently pursuing a Masters of Public Administration at Indiana University-Purdue University Indianapolis. Dr. Alfred Skolnick:retired from the Navy in 1983 with the rank of captain. He is president of System Science Consultants (SSC) specializing in strategic planning technical program definition technology assessment and engineering analyses on selected matters of national interest. Dr. Skolnick taught mathematics and management sciences at University of Virginia and Marymount University. He is adjunct faculty at Northern Virginia Community College. From 1985 to 1989 he was president of the American Society of Naval Engineers. In the Navy he served at Applied Physics Laboratory/The Johns Hopkins University then aboard USSBoston(CAG-1) and played leading roles in several weapon system developments inertial navigation (Polaris) deep submergence (DSRV) and advanced ship designs (SES). He later was director Combat System Integration Naval Sea Systems Command and head Combat Projects Naval Ship Engineering Center. In 1975 he became a major project manager and led the Navy's High Energy Lasers Program in 1981 he was assigned all Navy Directed Energy Weapons development efforts. He was vice president advanced tech

The military services are being moved in the direction of performance-based specifications and standards. They are being steered against dictating ''how to'' produce an item since such action forecloses on the ability to gain access to components or technology that may have a commercial equivalent. Why should the engineering community embrace the new approach? Aside from the obvious weight of it being approved policy, therefore currently mandated, it warrants examination because it is the correct approach at this time when applied to appropriate products. Military specifications and standards are to be displaced then, by acceptable alternative contractor design solutions. Industry bidders will be allowed to propose the particular design details, permitting procurement flexibility by contractually citing only system level or interface requirements, both physical and functional. Hopefully, this can broaden the industrial base and increase competition with reduced costs to follow. Conceptually, the approach appears both performance-sensible and cost-attractive (there are, of course, consequent risks) but how does implementation proceed? Is it possible to pursue the goals envisioned along paths that are not in themselves experimental? Can the American postulate, minimal loss of life and limb to U.S. military people, continue to be honored? Experience and track record elsewhere imply encouraging possibilities in select situations-useful prospects are identified and discussed in practical terms.

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THE CALLING(SM) NETWORK - A GLOBAL WIRELESS COMMUNICATION-SYSTEM

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第1期12卷 45-61页

作者： TUCK, EF PATTERSON, DP STUART, JR LAWRENCE, MH Calling Communications Corporation. 1900 West Garvey Ave South. Suite 200 West Covina CA 91790 USA. Chairman of Calling Communications Corporation. He is also the Managing Director of Kinship Venture Management Inc. the general partner of Kinship Partners 11 and a General Partner of Boundary the general partner of The Boundary Fund. As a venture capitalist he has founded or participated in founding several telecommunications companies including Calling Communications Corporation Magellan Systems Corporation manufactures of Global Positioning System receivers Applied Digital Access manufacturer of DS-3 test access and network performance monitoring equipment Endgate Technology Corporation specialists in satellite phased array antennas and Poynting Systems Corporation. now a division of Reliance Corporation manufacturers of fibre optic transport equipment. He was a founder of Kebby Microwave Corporation where he invented the first solid-state. frequency-modulated commercial microwave link system. The company was acquired by ITT Corporation where he rose to the position of V.P. and Technical Director of ITT North America Telecommunications Inc. Subsequently he was V.P. of Marketing and Engineering at American Telecommunications Inc. (ATC). He was founding Director of American Telecom Inc. a joint venture between ATC and Fujitsu and has served on more than 20 boards of directors including those of three public companies. He has authored articles on microwave engineering and telephone signalling and was a contributor to Reference Data For Radio Engineers. He is a graduate of the University of Missouri at Rolla where he was later awarded an honorary Professional degree and serves on its Academy of Electrical Engineering. Mr Tuck is a Senior Member of the IEEE a Fellow of the Institution of Engineers (Australia) a Professional Member of the AIAA and a registered professional engineer in three states. More than 25 years of experience in the telecommunications industry where he has been responsibl

There is a very large demand for basic telephone service in developing nations, and remote parts of industrialized nations, which cannot be met by conventional wireline and cellular systems. This is the world's largest unserved market. We describe a system which uses recent advances in active phased arrays, fast-packet switching technology, adaptive routeing, and light spacecraft technology, in part based on the work of the Jet Propulsion Laboratory and on recently-declassified work done on the Strategic Defense Initiative, to make it possible to address this market with a global telephone network based on a large low-Earth-orbit constellation of identical satellites. A telephone utility can use such a network to provide the same modern basic and enhanced telephone services offered by telephone utilities in the urban centres of fully-industrialized nations. Economies of scale permit capital and operating costs per subscriber low enough to provide a service to all subscribers, regardless of location, at prices comparable to the same services in urban areas of industrialized nations, while generating operating profits great enough to attract the capital needed for its construction. The bandwidth needed to support the capacity needed to gain these economies of scale requires that the system use K(alpha)-band frequencies. This choice of frequencies places unusual constraints on the network design, and in particular forces the use of a large number of satellites. Global demand for basic and enhanced telephone service is great enough to support at least three networks of the size described herein. The volume of advanced components, and services such as launch services, required to construct and replace these networks is sufficient to propel certain industries to market leadership positions in the early 21st Century.

关键词： LOW EARTH ORBIT SATELLITE COMMUNICATIONS FAST PACKET SWITCHING EARTH FIXED CELLS ADAPTIVE ROUTEING LIGHT SPACECRAFT K(A) BAND PHASED-ARRAY ANTENNAS

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APPLICATION OF TITANIUM IN SHIPBOARD SEAWATER COOLING SYSTEMS

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NAVAL ENGINEERS JOURNAL 1987年第3期99卷 124-134页

作者： ADAMSON, WL SCHUTZ, RW Wayne L. Adamson:is currently head of the Fluid Systems and Machinery Analysis Branch of the David Taylor Naval Ship Research and Development Center Annapolis Maryland. Mr. Adamson has conducted and directed research and development of heat exchangers condensers desalination equipment pumps and piping systems. He has been employed at DTNSRDC since 1957. During the past 10 years he has been actively involved in the development of titanium for shipboard machinery particularly for application in heat exchangers and steam condensers and in the evaluation of fouling and fouling control methods for piping and heat exchanger systems. Mr. Adamson is a member of ASME and ASNE having previously served as secretary for the Flagship Section and as a member of the ASNE Day Papers Committee. He has had several technical papers published in the Naval Engineers Journal as well as in other technical journals and books. He holds a bachelor of mechanical engineering degree (1962) and a master of science in mechanical engineering degree (1966) from Georgia Institute of Technology and a master of science in governmental administration from George Washington University (1969). He is a registered professional engineer in the State of Maryland. Ronald W. Schutz:received his B. S. (Cum Laude) and M. S. degrees in inorganic electrochemistry from Rensselaer Polytechnic Institute in Troy New York. He is a recipient of the 1981 A. B. Campbell Award for young authors from the National Association of Corrosion Engineers. He has eleven years experience with corrosion research product development and industrial application of titanium alloys. He has presented and published more than twenty technical papers including reference handbook articles on the subject of titanium corrosion behavior and related application guidelines. He currently holds position of supervisor industrial product development and corrosion research at TIMET Corp. Division of TMCA Henderson Nevada. Mr. Schutz is a member of ASTM and NACE.

Titanium alloys are evaluated as an alternative to the current copper-nickel components now employee in U.S. Navy surface ship seawater cooling systems. Titanium offers a solution to the accelerated seawater corrosion and erosion related attack being experienced in seawater systems aboard CG-47 class cruisers as well as other ship classes and can provide a means for extending service life and substantially improving reliability. Both the positive and potentially negative aspects of utilizing titanium in piping and heat exchangers are reviewed. Titanium's excellent resistance to corrosion and erosion attack, good yield strength and relatively low density permit use of thinner-walled, reduced diameter piping and heat exchanger tubing (relative to copper-nickel) and thus offer reduced system weight and volume. System design strategies are discussed for eliminating or greatly mitigating the adverse effects of galvanic corrosion and marine biofouling, the two major concerns when applying titanium in seawater piping and heat exchanger systems. An overall assessment of titanium versus copper-nickel alloys is provided with regard to piping and heat exchanger fabrication, cost, performance, design criteria, piping component (valves, pumps, etc.) selection criteria, and operational limitations. Specific topics addressed as part of that assessment include: (1) shipyard fabricability of titanium piping systems and onboard repair; (2) biofouling experience and biofouling control techniques with titanium in seawater; (3) galvanic corrosion effects when titanium is coupled to active (less noble) metals and the strategies for eliminating the risk of galvanic attack. The viability of titanium for surface ship seawater systems is summarized, and areas of future work are discussed with the intent of providing guidance for successful application of titanium in shipboard seawater systems.

关键词： TITANIUM AND ALLOYS

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