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International Conference on Solid State Sensors and Actuators (TRANSDUCERS)

作者： M. Mehregany S.M. Phillips E.T. Hsu J.H. Lang Electronics Design Center Department of Electrical Engineering & Applied Physics Case Western Reserve University Cleveland OH USA Laboratory for Electromagnetic & Electronic Systems Department of Electrical Engineering & Computer Science Massachusetts Institute of Technology Cambridge MA USA

The detailed operation of variable capacitance harmonic (or wobble) side-drive micromotors was studied through gear ratio measurements. The gear ratio of the wobble micromotor is affected by wear in the bearing and by rotor slip. Rotor slip is a function of motive torque magnitude, excitation angle, and friction torques. The gear ratio of a wobble micromotor can be expressed as a constant term plus a term that accounts for rotor slip. The constant term is the nominal gear ratio which is equal to the bearing radius divided by the bearing clearance. The rotor slip term is directly proportional to the bushing friction torque and inversely proportional to the square of the excitation voltage. Micromotor operation in air as opposed to nitrogen demonstrates a significantly larger bushing friction torque.< >

关键词： Micromotors Gears Friction Insulators Rotors Contacts Electromagnetic measurements Torque Nitrogen Electric variables measurement

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COMPUTER-AIDED MANUFACTURING OF ADVANCED MICROWAVE MODULES

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INTERNATIONAL JOURNAL OF MICROWAVE AND MILLIMETER-WAVE COMPUTER-AIDED engineering 1991年第1期1卷 90-111页

作者： PAVIO, AM PAVIO, JS CHAPMAN, JE BOGGAN, GH Texas Instruments Incorporated P.O. Box 655474 Dallas. Texas 75265 Jeanne Pavio is the Manager of the Microwave Advanced Packaging Group at Texas Instruments where she has been cmployed since 1980. She received the BA degree in 1971 and the MS in 1972 both from the University of Connecticut. Her experience base has included the fabrication and assembly of thick and thin film hybrids. At the Texas Instruments Hybrid Microelectronics Laboratory Jeanne implemented nitrogenfireable thick film for ceramic application in surface-mount technology and hybrids. For the last six years she has focused on the automated assembly and packaging of GaAs Monolithic Microwave Integrated Circuits and devices. This has encompassed development of fluxless furnace reflow and void-free vacuum reflow of GaAs components as well as development of automated wirebonding to GaAs Microwave Hybrids. She was instrumental in directly applying this technology to active phased array module production. Her efforts presently involve the implementation of high-volume techniques and automation for insertion of MMIC technology in a cost-effective highvolume environment. She has authored numerous papers involving hybrid fabrication and assembly technology and in particular involving automated assembly and packaging of GaAs MMIC devices. James E. Chapman Jr. was born in Dallas Texas in 1943. He received the BS and MS degrees in Electrical Engineering from Southern Methodist University (SMU) in 1966 and 1968 respectively. During this time he was associated with the Semiconductor Group of Texas Instruments Incorporated as an undergraduate engineering cooperative student working with various silicon products and processes. Mr. Chapman is currently a Senior Member of the Technical Staff assigned to the Microwave Technology and Products Division of the Defense Systems and Electronics Group. In this position he is currently technical director of the Technology Development for Solid-state Phased-Arrays (TDSSPA) Program. This program is a task-ordere

The application of computer-aided manufacturing (CAM) techniques to the assembly and test of a low-cost, high-volume X-band Radar T/R module will be investigated by highlighting the differences between low frequency and microwave CAM methods, focusing on the difficulties of automated testing, evaluation, and circuit tuning. The problems encountered when implementing high-precision automated assembly and test methods, which include wire-bonding, soldering, piece-part placement, thin wafer GaAs probing, and a novel implementation of a microwave circuit laser-tuning technique will also be discussed. These CAM techniques, combined with integrated MMIC technology, are then used to illustrate a manufacturing philosophy targeted toward high-volume microwave module production.

关键词： Microwave devices

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MAGNETOHYDRODYNAMIC SUBMARINE PROPULSION systems

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NAVAL ENGINEERS JOURNAL 1991年第3期103卷 141-157页

作者： SWALLOM, DW SADOVNIK, I GIBBS, JS GUROL, H NGUYEN, LV VANDENBERGH, HH Daniel W. Swallomis the director of military power systems at Avco Research Laboratory Inc. a subsidiary of Textron Inc. in Everett Mass. Dr. Swallom received his B.S. M.S. and Ph.D. degrees in mechanical engineering from the University of Iowa Iowa City Iowa in 1969 1970 and 1972 respectively. He has authored numerous papers in the areas of power propulsion and plasma physics and currently is a member of the Aerospace Power Systems Technical Committee of the AIAA. Dr. Swallom has directed various programs for the development of advanced power generation systems lightweight power conditioning systems and advanced propulsion systems for marine applications. His previous experience includes work with Odin International Corporation Maxwell Laboratories Inc. Argonne National Laboratory and the Air Force Aero Propulsion Laboratory. Currently Dr. Swallom is directing the technical efforts to apply magnetohydrodynamic principles to a variety of propulsion and power applications for various marine vehicles and power system requirements respectively. Isaac Sadovnikis a principal research engineer in the Energy Technology Office at Avco Research Laboratory Inc. a subsidiary of Textron Inc. He received his B.S. in engineering (1974) B.S. in physics (1975) M.S. in aeronautics and astronautics (1976) and Ph.D. in physics of fluids (1981) at the Massachusetts Institute of Technology. Dr. Sadovnik has been involved in research work funded by DARPA concerning the use of magnetohydrodynamics for underwater propulsion. He has built theoretical models that predict the hydrodynamic behavior of seawater flow through magnetohydrodynamic ducts and their interaction with the rest of the vehicle (thrust and drag produced). In addition Dr. Sadovnik has been involved in research investigations geared toward the NASP program concerning the use of magnetohydrodynamic combustion-driven accelerator channels. Prior to joining Avco Dr. Sadovnik was a research assistant at MIT where he conducted experimental and

Magnetohydrodynamic propulsion systems for submarines offer several significant advantages over conventional propeller propulsion systems. These advantages include the potential for greater stealth characteristics, increased maneuverability, enhanced survivability, elimination of cavitation limits, greater payload capability, and the addition of a significant emergency propulsion system. These advantages can be obtained with a magnetohydrodynamic propulsion system that is neutrally bouyant and can operate with the existing submarine propulsion system power plant. A thorough investigation of magnetohydrodynamic propulsion systems for submarine applications has been completed. During the investigation, a number of geometric configurations were examined. Each of these configurations and mounting concepts was optimized for maximum performance for a generic attack class submarine. The optimization considered each thruster individually by determining the optimum operating characteristics for each one and accepting only those thrusters that result in a neutrally buoyant propulsion system. The results of this detailed optimization study show that the segmented, annular thruster is the concept with the highest performance levels and greatest efficiency and offers the greatest potential for a practical magnetohydrodynamic propulsion system for attack class submarines. The optimization study results were used to develop a specific point design for a segmented, annular magnetohydrodynamic thruster for an attack class submarine. The design point case has shown that this thruster may be able to provide the necessary thrust to propel an attack class submarine at the required velocity with the potential for a substantial acoustic signature reduction within the constraints of the existing submarine power plant and the maintenance of neutral buoyancy. This innovative magnetohydrodynamic propulsion system offers an approach for submarine propulsion that can be an important contributio

关键词： Ship Propulsion

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Control logic and latching to the Faraday Cup experiment on the wind laboratory

Control logic and latching to the Faraday Cup experiment on ...

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Midwest Symposium on Circuits and systems (MWSCAS)

作者： A. Mavretic A. Konstantinidis E. Gergin R. Zhou Microelectronics Research Laboratory Department of Electrical Computer and Systems Engineering Boston University Boston MA USA

A satellite-mounted instrument has been developed to measure the energy spectrum of the solar proton flux in the solar wind. The instrument consists of a sensor (Faraday Cup), an analog signal processing chain, a high-voltage modulator, and a digital section, which is described. The functions of the digital section are (a) to interface with the main processor, (b) to provide the logic signals to the analog circuitry, (c) to deliver the necessary bit pattern to the high-voltage modulator, (d) to provide the calibration mode signals when necessary, and (e) to synchronize the sequence of events at the beginning of every spacecraft rotation. As with all space projects, primary concerns beyond the logical functionality consisted of circuit power consumption, instrumental mass, radiation tolerance levels, stability with respect to temperature, and relative ease of component procurement. The NASA WIND spacecraft will carry the experiment and launch in December of 1992.< >

关键词： Logic Instruments Digital modulation Signal processing Circuits Space vehicles Energy measurement Protons Sensor phenomena and characterization Digital signal processing

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Identification of faulty processing elements by space-time compression of test responses

Identification of faulty processing elements by space-time c...

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IEEE International Test Conference

作者： M.G. Karpovsky L.B. Levitin F.S. Vainstein Research Laboratory of Design and Testing of Computer Hardware Department of Electrical Computer and Systems Engineering Boston University Boston MA USA

A novel approach to the identification of a faulty processing element, based on an analysis of the compressed response of the system, is proposed. The test response is compressed first in space and then in time, and a faulty processing element is identified by a hard-decision decoding of the corresponding space-time signature. The overhead analysis and the solution for the hardware minimization problem are presented for several important classes of systems. The proposed method results in considerable hardware savings.< >

关键词： Fault diagnosis System testing Hardware design engineering Decoding Laboratories systems engineering and theory Educational institutions Vectors System buses

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Navigation system with map-matching method

Navigation system with map-matching method

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International Congress and Exposition

作者： Tanaka, Jiro Hirano, Kazuo Nobuta, Hiroaki Itoh, Toshiyoki Tsunoda, Sellchi Vehicular Systems and Electronics Department Vehicular Technology Laboratory Sumitomo Electric Ind. Japan Electronics Department Automotive Electrical and Electronics Division Sumitomo Electric Ind. Japan Electronics Research Laboratory Central Engineering Laboratories Nissan Motor Co. Ltd. Japan Electronics Design Department Nissan Motor Co. Ltd. Japan

This paper describes a navigation System for private automobiles. This system shows the accurate position of the vehicle on a CRT map display and also displays useful Information such as the locations of hotels, golf clubs, etc. A sophisticated map matching method is employed to find the vehicle's position. In this method, a set of correlation coefficients between the locus and the mapped roads is used to determine the vehicle's location statistically. A unique automatic calibration function is also added to the magnetic field sensor to compensate for malfunctioning and detection errors caused by distortion due to the earth's magnetism and to magnetization of the vehicle at points of high field density such as railroad crossings. In this system, we can see the current position of the vehicle indicated by a pointer on the smooth scrolling map display. This digital map has scales of 1/25,000, 1/100,000 and 1/400,000 and covers all of Japan with two available display modes: "north up" and "heading up". This system also shows the direction and distance to whatever destination the user has chosen. This navigation system has been installed in Nissan's 1989 Cedric/Gloria and Cima models. Copyright © 1990 Society of Automotive Engineers, Inc.

关键词： Navigation systems

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A high speed pipelined CMOS accumulator for implementing numerically controlled oscillators

A high speed pipelined CMOS accumulator for implementing num...

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IEEE International Symposium on Circuits and systems (ISCAS)

作者： J. Yuan C. Svensson F. Lu H. Samueli LSI Design Center IFM Linköping University Linkoping Sweden Electrical Engineering Department Integrated Circuits and Systems Laboratory Los Angeles CA USA

A high-speed pipelined CMOS accumulator which is designed for implementing a rate-multiplier-type oscillator is introduced. In such an oscillator the carry overflow of an accumulator is simply utilized as the output. The approximation to the rate frequencies, the circuit realization, and the ways to update frequencies are discussed. SPICE simulations show that the utilizable clock rates are over 400 MHz for a 2- mu m p-well chip and over 650 MHz for a 1.6- mu m n-well chip.< >

关键词： Oscillators Frequency Clocks CMOS process Jitter SPICE Circuit simulation Communication system control Large scale integration CMOS logic circuits

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Near-Time-Optimal Control of a Robot Manipulator using new Approximation Techniques

Near-Time-Optimal Control of a Robot Manipulator using new A...

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American Control Conference (ACC)

作者： Greg Heinzinger Paul Jacobs John Canny Brad Paden Department of Electrical Engineering and Computer Science and The Electronics Research Laboratory University of California Berkeley CA USA Laboratoire d'Automatique et d'Analyse des Systems Toulouse France Department of Computer Science University of California Berkeley USA Department of Mechanical Engineering and Center for Robotic Systems in Microelectronics University of California Santa Barbara CA USA

We present a new approach for determining a time-optimal trajectory for a robot manipulator with actuator torque bounds. We find an approximation to a globally optimal trajectory which passes between two configurations will avoiding obstacles. Our algorithm accomplishes this by by dynamically generating and searching a finite graph. Our algorithm is guaranted to produce a trajectory that performs within a user-specified factor of a time-optimal safe trajectory.

关键词： Robot control Manipulators Computer science Torque control Jacobian matrices Actuators Algorithm design and analysis Approximation algorithms Gravity Tellurium

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Time-optimal trajectories for a robot manipulator: a provably good approximation algorithm

Time-optimal trajectories for a robot manipulator: a provabl...

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IEEE International Conference on Robotics and Automation (ICRA)

作者： G. Heinzinger P. Jacobs J. Canny B. Paden Department of Electrical Engineering and Computer Sciences and the Electronics Research Laboratory University of California Berkeley Berkeley CA USA Laboratoire d'Automatique et d'Analyse des Systemes Toulouse France Department of Computer Science University of California Berkeley CA USA Department of Mechanical Engineering and Center for Robotic Systems in Microelectronics University of California슠Santa Barbara Santa Barbara CA USA

An algorithm is presented for generating near-time-optimal trajectories for an open-kinematic-chain manipulator moving in a cluttered workspace. This is the first algorithm to guarantee bounds on the closeness of an approximation to a time-optimal trajectory. The running time and space required are polynomial in the desired accuracy of the approximation. The user may also specify tolerances by which the trajectories must clear obstacles in the workspace to allow modeling of control errors.< >

关键词： Robots Manipulators Approximation algorithms Optimized production technology Safety

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AN ANALYTICAL TWO-DIMENSIONAL PERTURBATION METHOD TO MODEL SUB-MICRON GAAS-MESFET

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IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES 1989年第9期37卷 1484-1487页

作者： DONKOR, E JAIN, FC Microelectronics Research Laboratory Electrical and Systems Engineering Department University of Connecticut CT USA

A two-dimensional analytical model has been developed for finding the potential distribution in submicron GaAs MESFETs. The potential distribution is obtained by solving Poisson's equation with nonrectangular boundary conditions using a perturbation method. The expression for the potential is used to derive the current-voltage relation for GaAs MESFETs having channel lengths ranging from 0.2 to 0.9 mu m. The model is applicable in the linear, saturation, and subthreshold regimes of the current-voltage characteristics. Numerically simulated results are compared with experimental data and are found to be in good agreement.< >

关键词： Perturbation methods Gallium arsenide MESFETs Analytical models Poisson equations Boundary conditions Electric variables Laplace equations Microwave oscillators design methodology

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