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Superconducting electron cyclotron resonance ion sources (ECRISs) using NbTi coils and optimized for 28 GHz resonant heating have been successfully operated for almost two decades. Moving to higher heating frequencies requires increased magnetic fields, but traditional racetrack-and-solenoid ECRIS structures are at their limit using NbTi. Rather than moving to a superconductor untested in this field, the Mixed Axial and Radial field System (MARS) being developed at Lawrence Berkeley National Laboratory employs a novel closed-loop-coil design that more efficiently utilizes conductor fields and will allow the use of NbTi in a next-generation, 45 GHz ECRIS. This article presents the design of the shell-based support structure central to the MARS-D magnet design, as well as structural analysis of its components and optimization of pre-load parameters that will guarantee its successful operation.

An electromagnetic proportional solenoid is used as a force control device to generate thrust force acting on a valve element in a hydraulic pressure control valve. However, a conventional proportional solenoid has the problem of hysteresis appearing in its current-thrust force characteristics, which is induced by friction and magnetic hysteresis. In order to reduce hysteresis, this paper proposes the three-phase ac solenoid that reproduces a pseudo-magnetic bearing. Its prototype reduces hysteresis and achieves the same performance as the conventional proportional solenoid. The magnetic pole shape and the current input condition considering the magnetic flux density saturation are presented based on electromagnetic field analysis., © 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

A superconducting self-shielding three-solenoid system with an adjustable shielding factor is developed, implemented, and characterized using a single antiproton in a Penning trap. With the tuned system, we suppress external magnetic field disturbances by up to a factor of 225 ± 15, allowing antiproton-to-proton charge-to-mass ratio comparisons with fourfold reduced frequency fluctuations and antiproton magnetic moment determinations with tenfold reduced uncertainty. © 2019 authors. Published by the American Physical Society.

type:Journal Article, A new electromagnetic rotary mechanism utilizing a friction drive is proposed. An electromagnetic vibration excited on a permanent magnet is converted to a rotary movement through a frictional force. A trial motor, composed of a magnet rotor with inclined legs and an excitation coil, was fabricated and successfully operated. A no-load revolution speed up to 400 rpm and a reversible rotation were achieved. (C) 1998 American Institute of Physics., source:http://www.aip.org, source:https://doi.org/10.1063/1.367832

The Fermilab Mu2e experiment has been developed to search for evidence of charged lepton flavor violation through the direct conversion of muons into electrons. The transport solenoid is an s-shaped magnet that guides the muons from the source to the stopping target. It consists of 52 superconducting coils arranged in 27 coil modules. A full-size prototype coil module, with all the features of a typical module of the full assembly, was successfully manufactured by a collaboration between INFN-Genoa and Fermilab. The prototype contains two coils that can be powered independently. To validate the design, the magnet went through an extensive test campaign. Warm tests included magnetic measurements with a vibrating stretched wire and electrical and dimensional checks. The cold performance was evaluated by a series of power tests and temperature dependence and minimum quench energy studies.

The control software of the CERN Compact Muon Solenoid experiment contains over 27 500 finite state machines. These state machines are organised hierarchically: commands are sent down the hierarchy and state changes are sent upwards. The sheer size of the system makes it virtually impossible to fully understand the details of its behaviour at the macro level. This is fuelled by unclarities that already exist at the micro level. We have solved the latter problem by formally describing the finite state machines in the mCRL2 process algebra. The translation has been implemented using the ASF+SDF meta-environment, and its correctness was assessed by means of simulations and visualisations of individual finite state machines and through formal verification of subsystems of the control software. Based on the formalised semantics of the finite state machines, we have developed dedicated tooling for checking properties that can be verified on finite state machines in isolation. © 2012 Elsevier B.V. All rights reserved.

Control systems can vary from small and simplex to large and complex, but in all cases the systems consist of a controller, at least one actuator (as simple as a solenoid) and enough sensors to determine the result of the actuation, or in other words, the state of the system. In many cases, the size of the system, meaning either the physical size of the components, or the distance separating the sensors from the controller, presents problems in wiring, noise immunity, and power distribution. By configuring the control system to use distributed smart nodes, these problems are mitigated to various degrees determined by the requirements of the system and the amount by which control can feasibly be distributed., Presented at the International Instrumentation Symposium and MFPT 2013 Joint Conference (59th) held in Cleveland, OH on 13-15 May 2013.

We address the issue of the fallacies associated with the gauge concept in electromagnetism. Brief, elementary arguments suffice to demonstrate the fallacies. The simplicity of the proofs indicates that the norms of the scientific method have been neglected on this topic.

Agricultural vehicles use electronic control units (ECUs) as control system. HistoricallyECUs have only been equipped with a minimum of features. With therecent progress in electronics, which have made components faster, smaller andcheaper, the trend is now to integrate more advanced functionality into the ECUs. Agricultural vehicles are present all over the world and they have to operateunder a wide variety of conditions. This put high requirements on the system andit is critical that a modern ECU can detect and locate errors. For an ECU to beable to operate on a world-wide market it is required to be flexible, expandableand robust. In addition to these requirements it is also wanted that an ECU havea long lifespan and a low cost. In this thesis different problems that modern ECUs have to face are investigated.Suggestions of how to solve these problems are also presented. Thereare two focuses in the thesis, 1) how ECUs can acquire information from its inputs/outputs; and 2) the requirements of the ECU hardware. This thesis does not aim to deliver a fully specified system description butrather to provide an overview of how an ECU can be designed and which problemsthat it has to face. A selection of areas of ECU design which are investigated in this thesis are,1) typical inputs/outputs; 2) analog-to-digital converters and their application; 3)how multiplexers can be used; 4) requirements of general purpose inputs/outputs(GPIO); 5) monitoring of a controller area network (CAN); 6) power-supply requirementand monitoring; 7) monitoring of the vehicle’s battery; 8) memory; 9)requirement of the microcontroller (MCU);Agricultural vehicles use electronic control units (ECUs) as control system. HistoricallyECUs have only been equipped with a minimum of features. With therecent progress in electronics, which have made components faster, smaller andcheaper, the trend is now to integrate more advanced functionality into the ECUs.Agricultural vehicles are present all over the wo

We introduce a class of group endomorphisms - those of finite combinatorial rank - exhibiting slow orbit growth. An associated Dirichlet series is used to obtain an exact orbit counting formula, and in the connected case this series is shown to to be a rational function of exponential variables. Analytic properties of the Dirichlet series are related to orbit-growth asymptotics: depending on the location of the abscissa of convergence and the degree of the pole there, various orbit-growth asymptotics are found, all of which are polynomially bounded., QC 20110127

Agricultural vehicles use electronic control units (ECUs) as control system. HistoricallyECUs have only been equipped with a minimum of features. With therecent progress in electronics, which have made components faster, smaller andcheaper, the trend is now to integrate more advanced functionality into the ECUs. Agricultural vehicles are present all over the world and they have to operateunder a wide variety of conditions. This put high requirements on the system andit is critical that a modern ECU can detect and locate errors. For an ECU to beable to operate on a world-wide market it is required to be flexible, expandableand robust. In addition to these requirements it is also wanted that an ECU havea long lifespan and a low cost. In this thesis different problems that modern ECUs have to face are investigated.Suggestions of how to solve these problems are also presented. Thereare two focuses in the thesis, 1) how ECUs can acquire information from its inputs/outputs; and 2) the requirements of the ECU hardware. This thesis does not aim to deliver a fully specified system description butrather to provide an overview of how an ECU can be designed and which problemsthat it has to face. A selection of areas of ECU design which are investigated in this thesis are,1) typical inputs/outputs; 2) analog-to-digital converters and their application; 3)how multiplexers can be used; 4) requirements of general purpose inputs/outputs(GPIO); 5) monitoring of a controller area network (CAN); 6) power-supply requirementand monitoring; 7) monitoring of the vehicle’s battery; 8) memory; 9)requirement of the microcontroller (MCU);Agricultural vehicles use electronic control units (ECUs) as control system. HistoricallyECUs have only been equipped with a minimum of features. With therecent progress in electronics, which have made components faster, smaller andcheaper, the trend is now to integrate more advanced functionality into the ECUs.Agricultural vehicles are present all over the wo

Ion acceleration is achieved in a low-pressure solenoid-free plasma expanded by permanent magnet arrays. Although a permanent magnet normally forms cusp magnetic fields which prevents plasma diffusion and double layer formation, by employing double concentric arrays of permanent magnets, a constant field area, and a diverging magnetic field can be generated near the outlet of the plasma source. In the source, a rapid potential drop with 4 cm thickness from 50 V to 20 V is generated at the diverging field area for 0.35 mTorr and a supersonic ion beam accelerated through the potential drop is observed in the diffusion chamber. The beam energy can be increased up to over 40 eV with a decrease in gas pressure.

Due to their unique chemical structures and versatile functionalities associated with their structural characteristics many research groups are studying the materials science aspects of natural and synthetic DNA. In particular, interest in nanoscience and nanotechnology is accelerating the exploration of DNA for various properties such as electrical conductivity electron or hole transport and optical properties. In contrast, study on the magnetic properties of DNA is still in the infant stage. Recently, we reported for the first time that natural dsDNA in dry state (A-DNA) showed an extremely broad electron magnetic resonance (EMR) signal as well as an S-shaped magnetization-magnetic field (M-H) curve in SQUID measurements. The broad EMR signal was interpreted as a cyclotron resonance (CR), which is possible only when the double helical structure of each dsDNA coherently couples throughout the elementary fibrils resulting in the formation of lateral loop currents responsible for the S-shaped M-H curves in SQUID measurements. Both the EMR signals and the S-shaped magnetizations are found to be strongly correlated to each other. Assuming that the fibrillar dsDNA are in a morphologically heterogeneous structure, formation of such loop currents by the external field must be much more favored in ordered regions than in amorphous ones. In other word, the dsDNA can not only be a molecular solenoid in the single molecular level, but also can be a ferromagnetic in the well ordered regions due to coherently coupled bundles of DNA molecular solenoids. Therefore, if one introduces a magnetic dipole into the DNA molecular solenoid, a strong enhancement of DNA susceptibility is expected to occur as in an electrical solenoid with a magnetic bar. In this respect, we tried to insert various stable radicals into the dsDNA and succeeded in observing strong enhancements in their magnetic susceptibilities., Produced in collaboration with the Department of Polymer Science & Engineering, Chosun University, Gwangju, Korea and the Materials and Manufacturing Directorate, US Air Force Research Laboratory, Wright-Patterson Air Force Base, OH. To be included in the monograph 'Biotronics,' edited by Dr. James Grote, for publication by SPIE Press in 2009. The original document contains color images. All DTIC reproductions will be in black and white.

The high-frequency impedance of a planar solenoid with a thin magnetic core is theoretically investigated using the magnetostatic Green’s function formalism. It is shown that the electrical behavior of the solenoid depends on how the magnetic field induced by the current-carrying coil is coupled to the different magnetostatic modes of the core. The magnetic response of the core in each mode is determined by an effective susceptibility matrix which depends on exact, but mode-dependent demagnetization factors. Those factors determine the frequency of the magnetostatic excitations of the core, manifested as resonances in the impedance of the solenoid. Using the formalism developed, the effect of the core width and magnetic loss on the impedance of the device is studied., Electrical Engineering, Mathematics and Computer Science

The high-frequency impedance of a planar solenoid with a thin magnetic core is theoretically investigated using the magnetostatic Green’s function formalism. It is shown that the electrical behavior of the solenoid depends on how the magnetic field induced by the current-carrying coil is coupled to the different magnetostatic modes of the core. The magnetic response of the core in each mode is determined by an effective susceptibility matrix which depends on exact, but mode-dependent demagnetization factors. Those factors determine the frequency of the magnetostatic excitations of the core, manifested as resonances in the impedance of the solenoid. Using the formalism developed, the effect of the core width and magnetic loss on the impedance of the device is studied., Electrical Engineering, Mathematics and Computer Science

An ongoing Army requirement is for actuators for guided munitions. This report describes an electromechanical actuator concept using a tubular solenoid. Preliminary test results reveal the capabilities and limitations of the actuator concept., The original document contains color images.

A granular NiFe thin film with large in-plane magnetic anisotropy and high ferromagnetic-resonance frequency developed for radio-frequency integrated circuit (IC) applications is presented. During the deposition, three-dimensional (3D) growth occurs, yielding NiFe grains (? ? 1.0??m). Nanonuclei (? ? 30–50?nm) are observed in single NiFe grains by atomic-force microscopy (AFM). The in-plane magnetic anisotropy is estimated to be ? 50?mT. The frequency-dependent complex permeability is extracted. By taking the NiFe film as a magnetic core, solenoid-type inductors are fabricated and demonstrated and show a high operating frequency ( ? 5.5?GHz) with a maximum quality factor ( ? 3)., Electrical Engineering, Mathematics and Computer Science

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Physics, 1979., MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE., Includes bibliographical references., by Edward Ames Hildum., B.S.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Physics, 1979., MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE., Includes bibliographical references., by Edward Ames Hildum., B.S.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Physics, 1979., MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE., Includes bibliographical references., by Edward Ames Hildum., B.S.

A granular NiFe thin film with large in-plane magnetic anisotropy and high ferromagnetic-resonance frequency developed for radio-frequency integrated circuit (IC) applications is presented. During the deposition, three-dimensional (3D) growth occurs, yielding NiFe grains (? ? 1.0??m). Nanonuclei (? ? 30–50?nm) are observed in single NiFe grains by atomic-force microscopy (AFM). The in-plane magnetic anisotropy is estimated to be ? 50?mT. The frequency-dependent complex permeability is extracted. By taking the NiFe film as a magnetic core, solenoid-type inductors are fabricated and demonstrated and show a high operating frequency ( ? 5.5?GHz) with a maximum quality factor ( ? 3)., Electrical Engineering, Mathematics and Computer Science

NPSAT1 is a gravity gradient friendly, prolate body designed to fly at 600 40 km inclined to 34.5 degrees. The satellite uses a magnetic 3-axis active attitude control system (ACS) using magnetic torque rods that interact with the Earth's magnetic field. This thesis accomplishes three goals. The first objective was to verify and to validate the magnetic attitude control system program and model developed by Leonard. The verification and validation process was completed in two steps. The first step accomplished an independent modeling of the Earth's magnetic field using MATLAB. The second step completed a verification via inspection of Leonard's ACS SIMULINK model. The verification confirmed that Leonard's modular sub components of the disturbance torques, the quaternion vectors, the Euler angles, the spacecraft kinematics and dynamics, and the ACS control laws conformed to current ACS empirical theory. The second goal was to establish a laboratory used to demonstrate the ACS robustness and ability to perform as designed. The laboratory was created to house an air-bearing platform that simulates NPSAT1 characteristics. The third goal was to perform hardware-in-the-loop experiments with the NPSAT1 ACS software and model. Hardware-in-the-loop tests were performed to the magnetic torque rods, torque rod driver circuit board, micro-controller computer, and control interfaces. Specifically, solenoid current tests, magnetic field determination tests, and digital-to-analog conversion tests were completed., The original document contains color images.

A new electric current sensor based on fiber Bragg grating tuned by giant magnetostrictive material rod is demonstrated in this paper. A fiber Bragg grating is firmly clung on a giant magnetostrictive rod that is put into the central pant of a solenoid, The Bragg wavelength of the fiber grating will shift when the uniform magnetic field in the solenoid changes. The rod will have elastic lengthening along the direction of the magnetic field. The grating resonant wavelength of fiber grating will shift as consequence of the rod lengthening. The relationship between the electric current and the wavelength shift is basically linear. The wavelength range of linear tuning is about O.9nm. The tuning sensitivity is about O.OOlnm/mA., Proceedings of SPIE, v4082, 26-27 Jul 2000,p275-277. This article is from ADA398019 Optical Sensing, Imaging and Manipulation for Biological and Biomedical Applications Held in Taipei, Taiwan on 26-27 July 2000. Proceedings

3-D qualitative tracking sonar - Five 40 kHz Murata transducers are configured as a center transmitter flanked by a pair of receivers lying along the horizontal axis and a pair of receivers lying along the vertical axis. Interrogation pulses are transmitted every 10 milliseconds. Simple logic determines which receiver in each pair detects an echo first. For example, if the top receiver detects an echo before the bottom receiver, the object must lie above the sensor horizon. A solenoid then activates a downward-directed air jet to move the sensor upward. A similar operation occurs for the left/right determination. A moving object traveling less than pi/2 radians/second relative to the sensor is tracked by the sonar. This sensor is nonlinear in sensing and control, resulting in a limit cycle about the bearing and elevation of the object. Damping fins make the mechanical system response behave as a first-order system and simplify the control of the sensor. The determination of object location is made qualitatively, by identifying first arrival echoes. Hence, no triangulation computations are performed. Advantages of this approach include: 1. The sonar works over the union of the transmitter/receiver echo detection regions, which is larger than the intersection required for triangulation. Triangulation methods require that two transducers detect echoes and, hence, operate only over the intersection of the transmitter/receiver regions. 2. The sonar reacts with the arrival of the first echo, the arrival of the echo to the other receiver in the pair being irrelevant. Since the sensor does not need to wait for the other echo, correction occurs as fast as possible., Presented at the Defense Advanced Research Projects Agency (DARPA) Air-Coupled Acoustic Microsensors Workshop held in Crystal City, Virginia on 24-25 August 1999.

Using a two-point closure theory, the Eddy Damped Quasi Normal Markovian (EDQNM) approximation, we have investigated the energy transfer process and triadic interactions of compressible turbulence. In order to analyze the compressible mode directly, the Helmholtz decomposition is used. The following issues were addressed: (1) What is the mechanism of energy exchange between the solenoidal and compressible modes, and (2) Is there an energy cascade in the compressible energy transfer process? It is concluded that the compressible energy is transferred locally from the solenoidal part to the compressible part. It is also found that there is an energy cascade of the compressible mode for high turbulent Mach number (Mt greater than or equal 0.5). Since we assume that the compressibility is weak, the magnitude of the compressible (radiative or cascade) transfer is much smaller than that of solenoidal cascade. These results are further confirmed by studying the triadic energy transfer function, the most fundamental building block of the energy transfer., Prepared in collaboration with INSA, Centre for Thermique de Lyon, France and Laboratoire de Mecanique des Fluides et d'Acoustique, France

The compressible nature of the source terms in Lighthill's acoustic analogy can be closed. For weakly compressible flows in the absence of thermoacoustic effects, the compressibility of the source field is known in terms of solenoidal modes of the vortical flow field. In such flows, the square of the fluctuating Mach number is small and this fact, coupled with the singular nature of the acoustic problem, and the fact that the phase speed of the acoustic sources is the advective speed, is used to formally close the compressible portion of the fluctuating Reynolds stresses. The closure resolves, as expressed in Crow's 1970 paper, the inconsistent incompressible approximation to Lighthill's source term. It is shown that the incompressible approximation to Lighthill's source term, accurate to order of the square of the Mach number, predicts an acoustic field accurate to order Mach number.

Winter extratropical cyclogenesis over the northern Gulf of Mexico is examined by assigning a synoptic classification to each winter cyclone which developed during the 41-season period 1950-51 to 1990-91. The classifications of 'frontal' and 'nonfrontal' cyclogenesis are used to differentiate between those cyclones which were analyzed to have formed along pre-existing, airmass-type frontal boundaries, and those which developed in the absence of such boundaries. Spatial distributions of cyclogenesis events indicate that the open water of the northwest Gulf tends to be a preferred region for cyclone initiation, for both the frontal and the nonfrontal cases. This is particularly evident during the coldest months, when sea surface temperatures exhibit a strong gradient along the continental shelf break. Case studies reveal that after a cold air outbreak, air which resides for an extended period of time over the continental shelf of the northwest Gulf becomes differentially modified by spatially varying fluxes of heat and moisture from the sea surface, resulting in the formation of an atmospheric baroclinic zone which lies well to the north of the polar front. A solenoidal circulation develops within the boundary layer, increasing convergence and cyclonic vorticity, and inducing a horizontal discontinuity in atmospheric stability. Thus, this region is a favored location for further cyclonic intensification, provided that the upper-level paftem is also favorable. Although a lack of surface data makes the processes which induce cyclogenesis in this region difficult to resolve, visible satellite imagery is suggested to be beneficial.

The feasibility of designing a permanent magnetic field system for the Phillips Laboratory Relativistic Klystron Oscillator (RKO) was investigated. It was determined that it is nearly possible to obtain the desired 0.5 T magnetic field within the size and geometry configuration constraints. However, whereas the current RKO design requires a uniform field for a 60 cm length, the permanent magnet design will provide a uniform field for 52 cm. The existing RKO magnet system has a weight of about 600 kg for the magnet, plus an additional 1500 kg for the laboratory power supply currently in use. The design weight for the permanent magnet presented here is about 800 kg total. A simpler, straight solenoid system was only briefly considered. Modest magnet improvements of a few percent may be expected in the next few years but large scale improvements are not expected.

Permanent magnet solenoids that employ radially oriented cladding to confine flux have found several applications of late. As the design of these solenoids becomes routine, it is inevitable that one must be able to quickly assess the feasibility of using the same in more complex gadgetry. Accordingly, this report compiles a catalog of permanent magnet solenoids and presents the required field in terms of aspect ratio, bulk and weight. An introduction to sculpting the field profile, if the design so demands, is also presented.

The advent of rare-earth permanent magnets (REPM) has brought the realization of novel magnetic structures that are not practicable otherwise. So different are these remarkable materials from the earlier magnets that conventional design wisdom is inadequate to fully exploit their unique characteristics. Indeed, the conventional wisdom can lead to error or to the employment of cumbersome procedures that are quite unnecessary for REPM's. The salutary characteristics stem from two basic attributes of rare earth materials: (1) large intrinsic moments per unit volume, and (2) extraordinarily high resistance to demagnetization by external or internal demagnetization fields. The approaches to magnetic design fall into four broad main types: (1) analogy of magnetic configurations to electrical circuits, (2) analytical solutions through Maxwell's equations, (3) reduction of permanent magnet arrays to distributions of pole densities or current sheets and inserting these distributions into Coulomb's law or the Biot-Savart law, and (4) brute-force computer solution of a tentative configuration (via two- or three-dimensional finite element analysis). We discuss all these approaches and employ them to solve illustrative examples.

This thesis describes the development of custom-built tactile feedback hardware and its integration with an available force-reflecting haptic interface. Design requirements were motivated strongly by the characteristics of the human tactile sense as well as the biomechanical characteristics of the human finger. The work explores the feasibility of various actuators, and selects a small solenoid actuator for application in a closed-loop force control tactile feedback system. An adaptive PI algorithm using continuously variable gain scheduling helps to compensate for nonlinearities in the solenoid actuator. The system demonstrates adequate closed-loop control, but the mass added to the force-reflecting haptic interface proves less than optimal. Design suggestions for future prototypes may reduce the mass added by the tactile feedback hardware by over 30%. The work concludes with recommendations for psychophysical research that will increase understanding of human performance in tasks using haptic feedback devices.

A multi-piston pump is provided which uses microprocessor controlled check ball valves to control flow rate of a fluid at the pump's outlet port. The pump includes nine cylindrical shaped chambers and associated reciprocating pistons which are driven by a cam attached to a shaft. The pump's shaft is coupled to the shaft of a motor which, in turn, drives the pump's shaft and cam resulting in a fluid, such as seawater, filling each of the nine chambers and then having the fluid forced from the chamber by the movement of its associated piston from bottom dead center to top dead center. A pressure transducer which monitors the pressure at the pump's outlet port and a shaft encoder which monitors the angular position of the pump's shaft respectively provide analog signals indicative of the pump's outlet port's pressure and the shaft's angular position. A microprocessor receives these analog signals in a digital form, processes the signals and provides digital pulse signals to either extend or retract the rod of nine solenoids depending upon the pressure at the pump's outlet port. Each of the nine solenoid rods when extended engage a check ball valve within one of the pumps nine inlet passageways allowing the passageway to remain open when the associated reciprocating piston is in a pumping stroke. This allows seawater to be discharged through the inlet passageway maintaining fluid flow at the outlet port at a pressure level which is commensurate with the intended use of the pump., Supersedes PAT-APPL-290 669-94.

A folded waveguide gyrotron-traveling- wave-amplifier comprises: an electron gun for transmitting an axis-encircling beam of electrons with large transverse energy along a first path having an axis; an RF source for producing and applying in a second path an RF input millimeter wave signal having a bandwidth in a preselected frequency domain and having a transverse electric field; a source for generating a solenoid magnetic field parallel to the axis along the first path; a beam collector; and an interaction circuit such as an H plane bend serpentine waveguide positioned within the solenoid magnetic field and having a narrow wall containing a beam tunnel hole for passing the axis encircling beam of electrons therethrough to the beam collector, an output end, and an input end for receiving and passing the RF input millimeter wave signal through the H plane bend serpentine waveguide to the output end to modulate the axis encircling electron beam. the modulated axis encircling electron beam amplifying the RF input signal and also broadening the instantaneous bandwidth of the amplified RF input signal through the negative mass instability in the fundamental forward space harmonic of both fast and slow wave regions in the preselected frequency domain. In a second embodiment, a double ridged TE folded waveguide is used in place of the H plane bend serpentine waveguide. In a third embodiment, there is no RF input signal and the interaction circuit generates an RF signal which is outputted from one of the input and output ends., Supersedes PAT-APPL-269 278-94, AD-A288 847.

The use of anthropomorphic teleoperated mechanisms has gained considerable attention as a means of performing tasks that require human-like control, but due to the nature of the environment, would be optimally accomplished without direct human contact in the particular workspace. These tasks include mine clearance, space operations, hazardous waste cleanup, and even surgery. In order to continue research into this method of remote, manual supervisory control, an anthropomorphic robot was monitored and tested with the results formulated into an operating manual intended to standardize system control. Further experimentation was conducted to examine various methods of implementing bilateral force feedback on the robot using a durable and cost effective system.

An optic fiber payout test system and apparatus is disclosed which is adapted for simulating the payout of fiber at high speeds. This optic fiber payout test apparatus is comprised of a projectile, a source of fiber attached to the projectile, and a pneumatic propulsion system to propel the projectile and initiate the payout of the fiber. The fiber payout test apparatus further comprises a projectile track system as well as a braking system which allows the projectile to be used safely within a laboratory environment. The optic fiber payout test apparatus also provides a means for testing the payout of fiber optic cable in a manner that simulates the high rate of speed and high accelerations encountered during free flight. This capability is important for the development of launched fiber optic guided weapons systems and in particular, air launched optic guided weapons systems., Supersedes PAT-APPL-85 895-93.

An improved, multi-store dispenser is described which uses a solenoid and spring combination to eject individual stores after an electrical pulse is sent from the transporting aircraft. As each store is loaded into the dispenser, the loading action forces a spring into a compressed mode and a latch is closed to prevent expulsion. An electric pulse trips a solenoid, which in turn causes the latch to release, thereby allowing the store to be ejected., Supersedes PAT-APPL-102 023-93, AD-D016 047.

A folded waveguide gyrotron-traveling-wave-amplifier comprises: an electron gun for transmitting an axis-encircling beam of electrons with large transverse energy along a first path having an axis; an RF source for producing and applying in a second path an RF input millimeter wave signal having a bandwidth in a preselected frequency domain and having a transverse electric field; a source for generating a solenoid magnetic field parallel to the axis along the first path; a beam collector; and an interaction circuit such as an H-plane bend serpentine waveguide positioned within the solenoid magnetic field and having a narrow wall containing a beam tunnel hole for passing the axis-encircling beam of electrons there through to the beam collector, an output end, and an input end for receiving and passing the RF input millimeter wave signal through the H-plane bend serpentine waveguide to the output end to modulate the axis-encircling electron beam, the modulated axis-encircling electron beam amplifying the RF input signal and also broadening the instantaneous bandwidth of the amplified RF input signal through the negative mass instability in the fundamental forward space harmonic of both fast and slow wave regions in the preselected frequency domain. In a second embodiment, a double-ridged TE folded waveguide is used in place of the H-plane bend serpentine waveguide. In a third embodiment, there is no RF input signal and the interaction circuit generates an RF signal which is out-putted from one of the input and output ends.

The performance of several small, seawater magnetohydrodynamic (MHD) thrusters was studied in a closed loop environment. Three different thrusters were designed, constructed, and evaluated. For the first time, videographic and photographic recordings of flow through an MHD thrusters were obtained. The MHD induced flowrate, thrust, and mechanical efficiency was measured/calculated for each thruster at different combinations of electric current and magnetic field strength. Direct determination of thrust, and subsequently of efficiency were not possible. Therefore, the hydraulic resistance of each different thruster was correlated with flowrate. This information was used in conjunction with the measured MHD induced flowrate to calculate the thrust and efficiency of each thruster. Experimental results were repeatable. A theoretical model was developed to predict the performance of each thruster. The results of this model are presented for one thruster at several magnetic field strengths at various electric currents. These predictions corresponded well with the measured/ calculated values of MHD induced flowrate and mechanical efficiency. Finally, several MHD thrusters with radically different configurations are proposed.

This is a continuation proposal on Microwave Emission from Relativistic electron Beams. Below we summarize the various research activities. All of the experimental studies described below will be performed using our Physics International 615MR Pulserad Accelerator with a maximum voltage of 500 kV and peak currents of 4 kA and the 1.5MV, 30kA Pulserad 110A. The electron beam is presently generated by a thermionically emitting, electrostatically focused, Pierce-type electron gun (250 kV, 250 A) removed from a SLAC klystron. An assembly of six focusing coils is designed so that their magnetic field lines lie along the zero-magnetic field electron trajectories. This field configuration gives the least scalloping of the electron beam (low transverse temperature) and allows the magnetic field amplitude to be varied over a wide range without greatly affecting the electron beam temperature. Only the inner portion of the beam is used; an aperture limits the beam radius to r sub b = 0. 254 cm. Consequently, the net current available for the different experiments is in the range of 1-8 A. In addition to the above gun, we have recently procured from SLAC a brand-new, state of the art, electron gun that can operate at 450 kV and a peak current of approximately 500 A. The advantage of this system over the previous one is our ability to operate at higher voltages and thus study the various coherent radiation mechanisms at considerably shorter wavelengths.

A safe and arm device has a cylindrical body from which a plurality of explosive leads diverge from a rotor movable through an arming angle to electrically and mechanically arm a plurality of detonators and has a rotary solenoid with a shaft oscillating a predetermined number of times when the device is to assume and armed condition. The device has an axle extending alongside the shaft, and a setback weight is mounted oil and helically coupled to the axle to motivate the axle through an angle actuating the rotor through the arming angle. The shaft bears an arcuate pawl having recesses, and the axle bears an arcuate cam having recesses juxtapositioned to the paw. Latch balls are mounted in the body between the paw and cam for movement partially into and from the recesses.

A generalization of the Kapchinskij-Vladimirskij (K-V) equilibrium for an electron beam in a solenoid is derived by keeping higher order terms in an expansion of a Vlasov equilibrium. The radial profile of the charge density increases with r, whereas the radial profile of the K-V is flat. Space charge depression effects, the shear in longitudinal momentum and the self-induced longitudinal diamagnetic field are included. Numerical simulations of the beam transport in the Spiral Line Induction Accelerator (SLIA) illustrate the results. Relativistic charged particle beams, Vlasov equilibrium, Solenoidal transport.

Under a preliminary testing task assignment of the Advanced Development of X-Ray Computed Tomography Application program, computed tomography (CT) has been studied for its potential as a tool to assist in failure analysis investigations. CT provides three-dimensional spatial distribution of material that can be used to assess internal configurations and material conditions nondestructively. This capability has been used in failure analysis studies to determine the position of internal components and their operation. CT is particularly advantageous on complex systems, composite failure studies, and testing under operational or environmental conditions. CT plays an important role in reducing the time and effort of a failure analysis investigation. Aircraft manufacturing or logistical facilities perform failure analysis operations routinely and could be expected to reduce schedules, reduce costs and/or improve evaluation on about 10 to 30 percent of the problems they investigate by using CT... Computed Tomography(CT), Failure analysis, Electromechanical System, Materials, Cost/benefit, Electronic, Honeycomb, Solenoid, Hydraulic, Nondestructive Evaluation(NDE).

Certain gyro-type electron beam devices require two tandem coaxial chambers with different uniform axial magnetic fields in their interiors. Therefore, there is a step in the field profile in the vicinity of the junction of the two chambers, which are sometimes of different diameter as well. Ah electric solenoid is usually employed to furnish such a field but the sources are bulky, cumbersome, and consumptive of energy, and provide only rough approximations to the ideal field profile. This report describes a permanent magnet field source that was designed to provide a constant axial field of 2 kOe in the larger of the two chambers and 0.5 kOe in the smaller. The basic field is provided by two tandem permanent magnet solenoids. The rather broad transition between the field values in the two chambers is considerably narrowed (approximately 50 percent) by the placement of a radially magnetized ring internal to the junction of the two solenoids. The field profile can be made to conform to that specified to within a few percent by addition of two axially magnetized rings.

A reliability prediction is performed in the early stages of a development program to support the design process. Performing a reliability prediction provides for visibility of reliability requirements in the early development phase and an awareness of potential degradation of the equipment during its life cycle. As a result of performing a reliability prediction, equipment designs can be improved, costly over-designs prevented and development testing time optimized. Performance of a reliability prediction for electronic equipment is well supported by standardized documentation in the form of military standards, specifications and handbooks. Such documents as MIL-STD-756 and MIL-HDBK-217 have been developed for predicting the reliability of electronic equipment. Development of these documents was made possible because the standardization and mass production of electronic parts has permitted the creation of valid failure rate data banks for high population electronic devices. Such extensive sources of quality and reliability information can be used directly to predict operational reliability while the electronic design is still on the drawing board.

A tunneling tip piezo is incorporated into various devices for measuring the effect of changes in environmental conditions (i.e., temperature, pressure, magnetic and electrical fields, etc) upon a material by sensing minute changes in the dimensions of the surface. The devices may be used to detect changes in environmental conditions or to determine physical properties of a material. (Author), Supersedes PAT-APPL-484 950-90, AD-D014 580.

An apparatus for protecting the image recording media in a tracking camera from destructive illumination. The apparatus includes a shutter assembly mounted between the lens and the camera and a sensor assembly mounted in juxtaposition with the camera so that a sensor at one end of the tube in the sensor assembly detects destructive illumination before it impinges on the lens. The sensor causes a signal to be passed through circuitry connecting to the shutter assembly, activating a rotary solenoid which moves a blade to an interrupting position between the lens and the camera until no further destructive illumination impinges on the sensor. The shutter blade return to a non-interrupting position when the sensor no longer receives destructive illumination., Supersedes PAT-APPL-664 897-91.

Consideration of the electromagnetic momentum density D x B associated with a parallel plate capacitor in the presence of a magnetic field parallel to the plates shows that the momentum is a property of the electromagnetic field in a dielectric (closely related to the polarization of the dielectric) rather than a matter of storing mechanical momentum in the dielectric. This has implications regarding transport of momentum by electromagnetic waves. The physical cause of group velocity in normally dispersive, non-dissipative media is the immobilization of part of the wave energy, the energy transport being due to just part of the energy density propagating at the phase velocity. Something equivalent occurs in the case of momentum flow, and the existence of non-propagating momentum is another characteristic of group velocity. In idealized dielectrics, all of the electromagnetic momentum associated with a wave field flows at the phase velocity; the non-propagating momentum involves an impulse in the direction of propagation delivered to the dielectric upon the establishment of the wave field, and an impulse in the opposite direction delivered to the dielectric upon its decay. Although this appears to describe storage of momentum in the dielectric, the second momentum transfer occurs whether or not the momentum delivered to the dielectric upon establishment of the wave field is retained by the dielectric for the duration of the wave field.

A uniform magnetic field is required to calibrate magnetic induction sensor coils. Two types of coil designs are considered; a single finite length solenoid and a coaxially split coil pair (Helmholtz coil). The design must be able to reliably predict the magnitude of the calibration field and its homogeneity, both radially and axially, to within certain tolerances. The experimental results of a design based on the split coil pair are given. Furthermore, it is suggested that the quasi-uniform field in the mid-plane of a split coil pair can be usefully extended by narrowing the gap of the conventional Helmholtz coil pair spacing. In such cases, the flux in a circular region in the mid-plane can approach the value that would exist for a perfectly uniform field because of the partial cancellation between fields greater than and less than the central field. The deviation of the central field from that of an infinitely long solenoid is also discussed. (Author), Errata sheet inserted.