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This paper is related to the current research project “AC Meter Duty Meter” run by The University of Newcastle and ACARP1. The main objective of the project is to develop an innovative condition monitoring tool for large industrial induction motors, which offers a superior fault prediction capability. The approach taken in the project has two distinctive features: it is based on measurement of main air gap flux and it relates motor condition to its duty. This paper will present an overview of the existing methods used in condition monitoring, especially those based on flux measurement. It will then explain about the advantages of the proposed main air gap measurement approach. Preliminary analysis of experimental data collected so far will be included to support the discussion. Finally, the findings of the paper will be summarised in conclusions. [ABSTRACT FROM PUBLISHER]

Induction heating is a process where a varying magnetic field is used to heat a conductor or workpiece. When a piece of metal or conductor is placed near a magnetic field created by energising a coil of wire, the magnetic field transfers energy into the conductor, thus heating it up. This paper presents three methods for modelling induction heaters at mains frequency. These models are known as the series equivalent circuit (SEC) model, the transformer equivalent circuit (TEC) model and finite element analysis (FEA). The performances of these models are compared with experimental results for a demonstration induction heater. The FEA gives the best fit to the measured values and the TEC model gives better results than the SEC model. [ABSTRACT FROM PUBLISHER]

This paper describes a multi-point Bidirectional Contactless Charging System (BCCS) in a charging station suitable for electric vehicle and plug-in-hybrid vehicle applications. Battery modules of different ratings, together with their charging interface is connected to their respective charging points through high frequency coreless coils are described. Such type of multilevel configuration is easy to modularize and extend and allows different kinds of batteries to work together. Modeling, design and control aspects of multi-point BCCS system are addressed in detail. A multi-point BCCS system is designed and simulated for a maximum power handling capacity of 200kW and analyzed for vehicle-to-grid and grid-to-vehicle operations. [ABSTRACT FROM PUBLISHER]

In the next generation near-field optical data storage systems, higher data transfer rate and higher data density require the optical pickup head to maintain a constant sub-micrometer flying height above the rotating disk surface without any collisions. However, suspension vibration and force disturbance, as well as disk vibration make it difficult to maintain the desired flying height during disk operation in the near-field optical disk drives (ODD). It is proposed in this paper to design a hybrid actuator system which combines both advantages of the flying slider used in hard disk drives and the voice coil actuator used in optical disk drives. Then based on the developed model of the hybrid actuator, an adaptive regulation approach is proposed to regulate the flying height at its desired value, despite the unknown vibrations and the unknown force disturbance. Simulation results are presented to illustrate the capability of the proposed adaptive regulation approach to achieve and maintain the desired flying height. [ABSTRACT FROM PUBLISHER]

The improved magnetic induction tomography (MIT) coil system which consists of the two-arm Archimedean spiral coil (TAASC) as excitation coil and the solenoid as receiver coil has much better performance in coil system sensitivity than the conventional MIT coil system which uses the solenoids as excitation coil and receiver coil. In this paper the theoretical sensitivity property for improved MIT coil system are studied fully. The magnetic fields produced by TAASC and solenoid are derived approximately based on the Biot-Savart law. The relations between the coil system sensitivity and the parameters (amplitude of excitation current, maximum outer radius and number of turns of TAASC, and number of turns and length of solenoid) of coil system are calculated. The results show that the sensitivity for improved MIT coil system is proportional to the number of turns of solenoid and electric current of TAASC, and can be improved with the increase of maximum outer radius of TAASC and radius of solenoid. The sensitivity is decreased as the length of solenoid increasing, and not significantly associated with the number of turns of TAASC. [ABSTRACT FROM PUBLISHER]

A square-slots loaded (SSL) radio frequency (RF) resonator using microstrip transmission line (MTL) is designed for a human body 3T MRI. The SSL RF resonator shows greater penetrated RF magnetic fields near the center of the phantom than traditional RF resonators using MTL. A multichannel coil using SSL RF resonators was also simulated and provides good parallel excitation performance. In addition, RF shimming for homogenization can be effectively controlled by adjusting the inputs of eight resonators. Numerical results were obtained using a spherical phantom and a realistic human body model at 3T to calculate B1+ fields. [ABSTRACT FROM PUBLISHER]

Printed coils design and optimization are crucial and important for wireless power transmission (WPT). Currently the methods to design printed coils are left with a number of choices that each has advantages and disadvantages in different situations. In this paper, both electromagnetic theory analysis and equivalent circuit modeling have been used together in theoretical analysis, design and optimization of the printed coils system. With these design procedure, we can obtain the optimal parameters like coupling coefficient K, the self and mutual Inductance and others in printed coils through electromagnetic theory analysis. And the received power and power transmission efficiency of printed coils system can be achieved by the formula derivation and Matlab simulation more precisely than any previous method for the printed coils system in magnetically resonant coupling WPT system consisting of coils and reactive elements. [ABSTRACT FROM PUBLISHER]

Seeker is an important unit of the most tactical missiles, which detects and tracks the target, and provides missile the target's position. The accuracy of the missile is highly relative to its seeker. A large number of seekers use a free gyroscope to keep the LOS (Line Of Sight) vector direct at the target. Under the torque given by the precession coil, the gyroscope will precess or turn to a certain aspect, which keeps the LOS vector direct at the moving target. In this study, we analysis the gyroscope's movement under the magnetic field created by running an electrical current through the precession coil. On this basis, we put forward a new method to increase the gyroscope's precession speed by 27% by change the waveform of the precession current. With the higher precession speed, the seeker will be able to track faster moving target. [ABSTRACT FROM PUBLISHER]

Shrapnel injury is a major cause of death in victims of bomb blast, land mines and gun fire. In this paper, a Giant Magneto Resistance (GMR) sensor based online surgical tool that helps to remove metal shrapnel from victim's body is presented. This tool is intended to guide the surgeon to the exact location of the shrapnel during surgery. Presently doctors rely on imaging systems to locate them before surgery. Effectiveness of surgery solely depends on the doctors' skill to trace them, as these images do not provide real-time information of the location of the shrapnel during surgery. Therefore, in some cases, the shrapnel, in spite of being visible in the images, may become untraceable during surgery. So in such cases, a sensing tool that can guide the doctor to the location of the shrapnel will be very effective. An inductive proximity sensor can serve this purpose, but its output can be affected by its lead inductance or other parasitic circuit parameters. Therefore in order to overcome such effects, a GMR based sensing tool is proposed here. The details and experimental results obtained from this tool are presented in this paper. The tool can detect both ferromagnetic and paramagnetic metal targets. [ABSTRACT FROM PUBLISHER]

The equivalent circuit for the relation between the impedance of the coil wound around the magnetic yoke and the permeability of the material was analyzed for a quantitative estimation of an initial permeability of materials from the impedance measurement of the magnetic yoke. The optimum design of the magnetic yoke for an impedance measurement is also considered. In addition, a potential of NDE for the hardness of deformed low carbon steel using the impedance measurement was confirmed experimentally. [ABSTRACT FROM PUBLISHER]

This paper presents the design of liquid detection sensor with low-frequency electromagnetic field. The purpose of this sensor is to detect a change in the conductivity or permittivity of the liquid. If the evaluation frequency is less than 100 kHz, skin effects would be negligible. This paper proposes sensor that consists of two cylindrical sensors, a solenoid coil and a cylindrical capacitor. For an ideal shape condition, estimation methods for inductance and capacitance have been already proposed. However, the practical issues need to be clarified. It starts with fabrication of several coils and capacitors, to confirm the validity of the estimation methods. From experimental results, it was found that, the estimation error and existence of the parasitic element could not be neglected. This paper also presents a liquid detection demonstration with fabricated sensors based on differences in conductivity and permittivity. [ABSTRACT FROM PUBLISHER]

We investigated the noise from amorphous wire magneto-impedance elements in a CMOS pulse sensor circuit and clarified the average current bias effect for low-noise magneto-impedance sensor operation. In order to raise the signal-to-noise ratio (SNR), a single-core head and multicore head were compared. We showed that the noise floor of the four-core head magneto-impedance sensor is lower than 1 pT/Hz1/2 for the frequency range of 20 to 500 Hz. This result will be useful for designing a high SNR magneto-impedance sensor based on amorphous wire in combination with a CMOS pulse circuit. [ABSTRACT FROM PUBLISHER]

Defect detection in metallic plates represents an important issue in metal industry, because its potential use in quality control process. Eddy current testing is one of the most extensively used nondestructive techniques for inspecting electrically conductive materials. The purpose of this paper is to present an eddy current testing system for surface defect detection in conducting materials using a giant magnetoresistive (GMR) sensor. An alternate magnetic field is produced by a solenoid and eddy currents are generated in the material under test. The GMR sensor was mounted inside the coil and the arrangement was adapted in the axis of a vertical machining center. In order to validating the measurement device, defects were induced by cracks machined in workpieces made of aluminum. Thus, the parts were scanned with the sensor prototype and a method to estimate the width and depth of the induced defects was proposed after analyzing the output voltage signal. [ABSTRACT FROM PUBLISHER]

We present an efficient method for simulating the impedance of a rectangular spiral coil in the high frequency regime based on the Partial Element Equivalent Circuit (PEEC) method. We use closed form expressions of the corresponding mixed potential integral equation, considering self and mutual inductance as well as capacitance between the elements of a rectangular spiral coil geometry. From the PEEC circuit elements, we abstract an equivalent circuit model that accounts for dominant field interactions. We compare the obtained impedance as a function of frequency with the results of a commercial field solver and benchmark the simulation duration. Our Matlab simulator is by a factor of 8.2 faster, which allows for quick optimization of the spiral coil. [ABSTRACT FROM PUBLISHER]

The identification distance of the traditional High Frequency (13.56MHz) antenna used in the access control system is only around several centimeters, bringing about an inconvenience for the users and decreasing the efficiency of the access system. This paper describes the design and calculation of a long-range identification antenna, whose identification distance can reach 0.9 meter, using two paralleled antennas set in-phase. In this way, the passenger can go through the access control system, just bringing a card (tag) instead of swiping it, and the tag can be detected and identified by the reader precisely. [ABSTRACT FROM PUBLISHER]

This paper presents an electrically small ferrite rod receive antenna which is electronically tunable over the majority of the HF band. The tunability allows the antenna to operate when detuned by nearby conductive objects. The small size makes the antenna particularly suitable for applications where larger antennas cannot easily be accommodated. This paper addresses the issues affecting the size of the antenna and its construction. A method of measuring the gain of the antenna is presented and the performance is compared to that of a full size half wave dipole. [ABSTRACT FROM PUBLISHER]

- In recent days, there has been major improvement on implantable biomedical systems that support most of the functionalities of implantable medical devices uses wires or wireless radiofrequency telemetry to communicate with circuitry outside the body. However, the wires are a common source of surgical complications, including breakage, infection and electrical noise. In addition, radiofrequency telemetry requires large amounts of power and results in low-efficiency transmission through biological tissue. Communication with implanted devices is usually accomplished with a wired connection or with wireless radiofrequency (RF) transmission. However, wires can break, become infected or introduce noise in the recording through movement artifacts or by antenna effects. Complications with wires are frequently reported with deep brain stimulation devices and with pacemakers and implantable cardioverter-defibrillators. Wireless RF telemetry has been used in several implantable medical devices to avoid the complications of wired implant. However, wireless RF telemetry requires significant power and suffers from poor transmission through biological tissue. RF telemetry also needs a relatively large antenna, which limits how small the implantable devices can be and prevents implantation in organs such as the brain, heart and spinal cord without causing significant damage. [ABSTRACT FROM PUBLISHER]

With the development of smart substations, much attention has been focused on the transient magnetic field (TMF) generated during switching operation in substations. In order to study the TMF, a portable integrated system based on Anisotropic Magneto-resistive (AMR) sensor has been developed. The system mainly consists of magnetic probe, sampling card, and industrial computer. A GPS has also been brought in to stamp the TMF events time. This system can record TMF across a bandwidth from DC to 5MHz and a dynamic range from 20mGs to 6Gs for at least 50ms continuously. Laboratory tests show that the system linearity is greater than 97%, the measuring error is less than 3% and the verified rising time of input magnetic field reaches 6.4μs. Field applications are presented at last, they show that the TMF is very complex but regular to some extent, and the stable magnetic fields are in conformity with operation theory. In conclusion, the proposed system is high sensitivity, wide dynamic and relatively wide bandwidth, and it is qualified to most applications in substations. [ABSTRACT FROM PUBLISHER]

In this paper, a robotics system is designed for the function of automatic gripping wires, and which is composed of computer vision system, milli-gripper and control system. In the robotics system, thin copper wires with a diameter of about 50–70 microns are manipulated through the positioning of a vision system, the motion of multi-freedoms control system and the gripping function of milli-gripper. A micro gripper is used to clamping the tip of copper wire, moving to the pad position and releasing wires. The vision system use a binocular stereo vision positioning principle, stereo images are offered by a stereo light microscope with two CCD cameras, and 3D position of copper wire tip is reconstructed based on image processing technology. The gripper is driven by magnetic force supplied by a magnetic structure designed in the robotics system. And the gripping action is executed through bending deformation of the cantilever being a leg of the gripper. This gripper has long distance of run and high response frequency. [ABSTRACT FROM PUBLISHER]

The crane and ground scheduling is the most important part of the inventory management. In the inventory management process if there are two or more warehouses and two or more cranes in each house, it becomes very difficult to obtain an optimal or near optimal solution under consideration of restrictions concerning ground logistic control and crane interference as well as many restrictions for Inventory optimization. In this paper, we first propose a scheduling problem taking account of multiple sub-warehouses and multiple cranes. In order to study the problem, we constructed and validated a system prototype using Petri net model and then propose a two stage hybrid scheduling algorithm, which finds a sub-optimal solution by starting from a feasible solution and solves the problem in a finite time. The applied result shows that the dynamic scheduling system plays an important role in the inventory management and the algorithm achieves satisfactory result. [ABSTRACT FROM PUBLISHER]

In this paper, a direct drive implementation scheme using a linear voice coil motor (VCM) is proposed and designed for LED die bonding application. Design specifications are obtained by real requirements. Finite element analysis of electromagnetic field is used to design the VCM. A prototype VCM was manufactured. The performance is evaluated experimentally and compared with that produced by simulation. To improve the design, a mathematical model of electromagnetic force in the voice coil motor is derived. An analytical optimization formulation is proposed to maximize the total force constants along a given stroke given constraints on motor size. This leads to a great improvement both in size and force performance. [ABSTRACT FROM PUBLISHER]

A single phase, single slot permanent magnet linear motor is designed and operated. It is a type of moving coil linear motor, with a view to achieve optimization in terms of input power, copper losses and efficiency of operation. The equations governing the motion and electrical circuit are written to obtain the electrical parameters. The optimization of magnetic circuit is achieved through electromagnetic simulation to reduce the flux leakage. It is required to optimize the coil length in order to fully utilize the magnet flux in the air gap. After accomplishment of design, the linear motor is used in the dual-opposed Stirling cryocooler and operating well. [ABSTRACT FROM PUBLISHER]

An electromagnetic based tracking method is proposed in this paper, which can provide 6D position and orientation information. This method is based on triaxial transmitting coils and triaxial sensing coils, which are based on the electromagnetic field. Transmitting coils fed with different frequency alternating current (AC) signals comprise the magnetic field source, which can be seen as three orthogonal magnetic dipoles. By extracting the amplitude and phase information from the triaxial sensing coils, 3D position and 3D orientation information of the sensing coils in the pre-defined localization coordinate system can be estimated using an appropriate algorithm. In this paper, an analytic method is proposed to realize the calculation, which can estimate the position and orientation of the sensing coils easily and fast. Simulation results indicate that this method has a good performance. [ABSTRACT FROM PUBLISHER]

It is believed that micro actuators and robots might introduce revolutionary changes in many advanced applications, such as nano manipulation and minimally invasive medicine. Many prototypes were recently developed, which could be powered either by micro organism, by onboard mechatronic systems or by remote magnetic fields. This paper presents two evolving designs, aiming at producing a micro motor which can be selectively remotely actuated by weak resonant magnetic fields. The core design concept is to design a spring-mass structure to transform the vibrations of a soft magnet into rotary outputs. The generated rotation can then be used to form revolute joints or to drive propellers. The proposed designs convert magnetic energy directly into mechanical work, avoiding complex components from tradition motor units such as windings, batteries, etc. [ABSTRACT FROM PUBLISHER]

In today's world we are surrounded by the most sophisticated & hi-tech microprocessor & microcontroller technology, which controls transport, finance, Electricity, Communications, etc. An EMP (Electro-Magnetic Pulse) has the destructive tendency to devastate any electronic equipment in its specified path range, causing electronic equipment to burn out. With the continuous development, use & dependability of modern day equipment, it is almost impossible for us go back from the current microelectronic generation. This makes the Electro-Magnetic Pulse one of the most deadliest & Terrifying weapon in the world causing huge collateral & infrastructural damage to any nation & her interests. This paper includes all the basses of Electro-Magnetic Pulse generation & it's possible causes & effects on the nearby electronic components within its specified range capability. Along with miniature prototypes that are developed, so as to demonstrate the effect of Electro-Magnetic Pulse on various smart & dumb devices & their consecutive role in Modern Warfare as Directed Energy Weapons (DEW's). Currently, there is a lot of research going on the ElectroMagnetic Pulse phenomenon. Scientists in military & defense organizations around the world are working on the EMP Technology & its application as a weapon in Military Warfare. There is even subsequent research going on in the shielding of crucial electrical & electronic components against an EMP attack. The current EMP shields developed can only prevent a small amounts of Electro-Magnetic Pulse. However, a perfect shield against an EMP attack of huge intensity is still not devised, although Ferro-Magnetic cages provides a protective shield against an EMP strike. However it's nearly impossible to realize every structure, building, Electronic gadget or vehicle shielded by Ferro-magnetic Cages. As it doesn't only cause inconvenience in its installation but even has a huge initial capital coast for its total installation, hence doesn't make it economically viable to construct. [ABSTRACT FROM PUBLISHER]

In recent years, the large penetration of wind power system is considered as an effective means for power production due to this continuously growing nature of wind power system, power utilities does not consider the power quality problems that are issued by the system. They are going for other power system stability analysis. This will produce an integration of large wind power system with the electrical network that are series compensated for ensuring bulk power transfer. But this series compensated transmission system will produce an unwanted effect of subsynchronous resonance. SMES (Super Conducting Magnetic Energy Storage) with STATCOM (Static Compensator) controller provide an efficient damping for Subsynchronous Resonance that will enhance power system stability in addition to real and reactive power compensation. And it will reduce MVA rating required by the STATCOM when it is operated alone. Here output of PV cell is used instead of a constant dc source. This work mainly concentrate for the coordinated operation of STATCOM control with SMES scheme for the series compensated wind power system for damping power system oscillation is simulated using MATLAB/SIMULINK in power system block set. [ABSTRACT FROM PUBLISHER]

This paper presents an untethered microrobot swimming in human blood vessels through electromagnetic actuation to manipulate bio/micro-objects using an acoustically oscillating bubble attached on the microrobot as a grasping tool. First, for the three-dimensional (3D) propulsion of the microrobot in arbitrary shaped blood vessels, an electromagnetic system consisting of the horizontal and vertical pairs of Helmholtz and Maxwell electric coils is designed and manufactured along with the verification of the magnetic flux density generated from the designed system with theory. Using the developed electromagnetic system, the propulsion of a spherical microrobot (800 μm dia.) made of a cylindrical magnet covered with clay is successfully demonstrated in x-y and x-z plains along with a T-shaped glass channel. Second, an acoustically oscillating bubble induced microstreaming is separately investigated by using a high speed camera integrated with a zoom lens and laser as a light source. When a bubble is acoustically excited by a piezoactuator around its natural frequency, it oscillates and simultaneously generates microstreaming and radiation forces, which can be used to manipulate (pull and push) neighboring objects. Finally, as the concept proof, the manipulation of a fish egg (800 μm dia.) in a microfabricated channel with tandem rectangular hills is experimentally achieved by the microrobot incorporated with an acoustically oscillating bubble. [ABSTRACT FROM PUBLISHER]

This paper presents the design and in vitro evaluation of magnetoelastic sensors intended for wireless monitoring of tissue accumulation in peripheral artery stents. The sensors, shaped like stent cells, are fabricated from 28-μm thick foils of magnetoelastic Ni-Fe alloy and are conformally integrated with the stent. The typical sensitivity to viscosity is 427 ppm/cP over a 1.1–8.6 cP range. The sensitivity to mass loading is typically 63,000–65000 ppm/mg with resonant frequency showing an 8.1% reduction for an applied mass that is 15% of the unloaded mass of the sensor. [ABSTRACT FROM PUBLISHER]

Much effort has been put into developing multi-channel retinal prosthetic devices. Currently, even the most advanced prostheses do not have enough channels to provide vision to a desirable level. In this paper, we present a system design and a packaging scheme for a 512-channel intraocular epiretinal implant. Both a wireless power coil (with high transfer efficiency) and a data coil are included for this intraocular system. Simulation of the interference between coils is investigated and the results show that the two coils can be put in a co-planar fashion using two notch filters to minimize interference. The complete package is demonstrated with a mechanical model with a parylene-C flexible circuit board, i.e., parylene flex, to show the placement of the IC chips, discrete components, and coils. It also shows the final folded device after surgical insertion into an eye to save space. The feasibility of the proposed structure has been successfully tested in vivo. Experimentally, the maximum allowable pulling force is measured by a dynamic mechanical analysis (DMA) machine to be 8N, which provides a large safety margin for surgery. [ABSTRACT FROM PUBLISHER]

This paper presents a new high quality factor parylene-based stacked 3D spiral inductor with Ni80Fe20 core for wireless power transmission system. To achieve multilayers, planarization of parylene by oxygen plasma etching was realized. Ni80Fe20 was added as the magnetic core to enhance the performance. The maximum quality factor of the designed circular double-layer inductor reached 99.3 at 60MHz, which is much higher than the square coils with the same area. The double-layer inductor shows a 408% increment of maximum quality factor compared with single-layer coil. Furthermore, inductors with magnet arrays exhibited better performance than those with one magnet. Forming the power transmission system with these 3D inductors, the minimum attenuation was −26dB at 118MHz. [ABSTRACT FROM PUBLISHER]

This paper presents a MEMS-based electromagnetic (EM) energy harvester for low frequency and low acceleration vibrations. The harvester is an improved version of [1], which operates with the frequency up conversion (FupC) principle. The former structure was composed of a low-frequency diaphragm carrying a magnet and 16 high-frequency cantilevers with coils. In this work, the phase difference between the coil outputs, leading to voltage cancellation in serial connection, has been eliminated by using a single coil placed on a diaphragm. Furthermore, the placement and the volume of the magnetic film have been modified for better magnetic coupling. The RMS values of the generated voltage and delivered power to an equivalent resistive load have been measured as 6.94 mV and 1.2 nW, respectively with 10 Hz, 3 mm peak to peak vibrations (0.6 g acceleration). About 32-fold increase in the peak power output has been demonstrated with the presented energy harvester with respect to the previous work. [ABSTRACT FROM PUBLISHER]

In this study, a novel planar inductor to detect the pressure sensor is proposed. The planar inductor consists of planar coil and CoFeB films. The proposed sensor exploits the inverse-magnetostriction effect to change the permeability of the CoFeB film by pressure load. This permeability variation will further result in the inductance difference of the planar inductor. Consequently the relationship between the pressure and inductance can be obtained by the inductance measurement. To demonstrate the presented concept, prototype inverse-magnetostrictive type pressure sensors with planar sensing inductor (Al planar coil and CoFeB films) have been implemented and tested. Sensitivity measurements show the gauge factor of the novel pressure sensor is approximate 280. To support the proposed concept, the vibrating sample magnetometer (VSM) measurements show the magnetic anisotropy of the CoFeB film (extracted from the hysteresis loops) is changed due to the applied pressure load. [ABSTRACT FROM PUBLISHER]

In this paper, a novel resonant magnetometer is demonstrated based on MEMS Technology. The proposed sensor consists of a square extensional mode resonator with a planar induction coil placed on top of the resonant plate. The sensor employs capacitive driving and electromagnetic induction to detect external magnetic field through the electromotive force in the induction coil. The operation principle, fabrication process as well as the measurement of the magnetic field sensor is demonstrated. Experimental result shows that the device offers a sensitivity of 3 μV/mT at its resonant frequency of f0 = 4.33 MHz in atmosphere pressure. [ABSTRACT FROM PUBLISHER]

We present the full testing and characterization results of a pneumatic-less high-speed roughing (vacuum) meso-pump that demonstrates, within our knowledge, the best near-atmosphere performance-up to date while obviating the conventional dependence on pneumatics (e.g. gas cylinders). The roughing pump operates completely all-electrically by manipulating multiple micro membranes utilizing only a single electromagnetic actuator, thus in the smallest packaged volume (22.8cc) of the same kinds while achieving a record vacuum of 206 torr within only 5 minutes. The single actuator operation is enabled by developing programmable micro hydraulics designs where multiple pump membranes were passively-controlled with designed time delays in a desired sequence. The fabricated prototype produced the maximum flow rate of 11.56 sccm at 50 Hz electromagnetic driving frequency; continually operated over 466 hours; and successfully demonstrated the timed actuation of multiple membranes utilizing only a single electromagnetic actuator. [ABSTRACT FROM PUBLISHER]

This paper reports on a cone-shaped micro coil for measuring an NMR (Nuclear Magnetic Resonance) signal of an MRI (Magnetic Resonance Imaging). A three dimensional cone-shaped micro coil was fabricated by pulling up an outer frame of a spiral patterned micro coil. Since there are supporting parts between the wiring, the cone-shaped micro coil has uniform pitch. By using this process, we fabricated the cone-shaped micro coil of 30 mm in diameter and 8 mm in height. The resistance and Q-factor of the coil were 2.14 Ω and 32.3 at 8.5 MHz. As a demonstration of MRI by the cone-shaped micro coil, we acquired MR images of a quail egg and an okra. [ABSTRACT FROM PUBLISHER]

This paper presents a new technique of converting mechanical energy to electrical energy that can be used to harvest mW — W power level from a vibrating surface of tens — hundreds microns amplitude. The technique uses an array of alternating north- and south-orientation magnets to enhance magnetic flux change by more than an order of magnitude. Experimental results show that a microfabricated energy harvester of 20mm×5mm×0.9mm (=0.09cc) weighing 0.5 gram generates an induced electromotive force (EMF) of Vp-p =30mV with 2.6μW power output (into 10.8Ω load) when it is vibrated at 290Hz with vibration amplitude of 11μm. Its macroscale version, that is scaled up to 51mm×51mm×10mm (=26cc) weighing 90 gram, generates an EMF of Vp-p=22V with 158mW power output (into 96Ω load) when it is vibrated at 82Hz with vibration amplitude of 414μm, and lights an incandescent light bulb. [ABSTRACT FROM PUBLISHER]

We present the fabrication of 3D-microtransformers combining a new type of multilayered magnetic core and coil winding with an automatic wirebonder. For the magnetic cores we stapled up to 30 layers of 20 μm thick amorphous metal layers with an industrial laminator. Intermediate layers of 10 μm thick double-sided sticky tape provided adhesion and electrical insulation. Electrical discharge machining was used to precisely cut these magnetic stacks to sub-millimeter cubes. To flip the cubes by 90° and assemble them onto a wafer for coil winding, we produced a receptor wafer providing magnetic landing sites. Subsequently, to wind a primary and secondary coil, one on top of the other, an automatic wirebonder was employed with 25 μm thick insulated Gold wire. A fabricated transformer with a core size of 0.9∗0.8∗1 mm3 yielded an inductance of 1412 nH and a coupling factor of 97%. The maximum transformer efficiency of 73% was measured at a load of 50 Ω. [ABSTRACT FROM PUBLISHER]

The stacking of metal/tungsten layers as the in-plane magnetic-coil for CMOS-MEMS magnetic sensor has been proposed and demonstrated for the first time. Magnetic fields introduce forces through in-plane coils to drive suspended spring-mass structure. Capacitance sensing electrodes could detect the dynamic response of spring-mass structure to determine magnetic fields. Such design has the following advantages: (1) Number of turns for proposed in-plane magnetic-coil is not restricted by the space and thin film layers, (2) in-plane magnetic-coil could respectively generate Lorentz and electromagnetic forces by out-of-plane and in-plane magnetic fields for multi-axes magnetic field detection, and (3) easy integration with CMOS-MEMS accelerometers and sensing circuits [1]. The design was implemented using the standard TSMC 2P4M CMOS process. A 400μm×300μm proof-mass with embedded in-plane magnetic-coil of 35-turns/5μm-wide is demonstrated. Measurement indicates the 3-axis magnetic fields were successfully detected using two monolithically integrated perpendicular sensing units. At 1atm, the sensor has the resolution of 319.9nT/rtHz (x-axis magnetic field), 296.5nT/rtHz (y-axis), and 121.6nT/rtHz (z-axis). [ABSTRACT FROM PUBLISHER]

This paper presents a magnetically actuated droplet platform for automated sample preparation and gene detection. Our platform integrates nucleic acid extraction using silicacoated magnetic particles with real-time polymerase chain reaction (PCR) on a single cartridge. The device consists of seven compartments in which reagent droplets are serially loaded. The assay utilizes solid phase nucleic acid isolation chemistry in order to purify genomic DNA from crude samples and elute the material in a PCR-ready buffer. Silicacoated magnetic particle provides a mobile solid phase that can be merged with and removed from reagents efficiently using a combination of planar coils and surface topographical features. Each droplet operation was characterized and evaluated. Using our platform, automated sample processing from whole blood to PCR-ready droplet, followed by amplification was performed successfully. This work demonstrates a fully integrated genetic assay platform for simple and efficient droplet manipulation. [ABSTRACT FROM PUBLISHER]

This paper considers the positioning of a motor in a vacuum gate valve which is used in a vacuum chamber. First, by using reinforcement of bearings' stiffness with permanent magnets, the fluctuation of the valve is suppressed. Next, by adjusting command signals and MR sensor's outputs, the repeatability of the positioning is improved. Moreover, three-dimensional dynamic analysis of the motor is performed by using magnetic analysis software “MagNet7.” Simulation results agree with experimental results. Finally, sequential operation of the valve is performed without mechanical contact in atmosphere and vacuum. [ABSTRACT FROM PUBLISHER]

In order to develop high-efficiency and small-sized hydrodynamic generators, a novel permanent magnet biased magnetic bearing which has a three-dimensional flux path was designed and fabricated. The magnetic bearing is small but has a strong bearing capacity. This paper clarifies the operation principle and dynamic characteristics of the fabricated magnetic bearing. The fabricated magnetic bearing showed good control performance in both the time and frequency domains. In addition, the rotor rotated stably up to 10000 rpm. Moreover, rotational loss of the magnetic bearing was about one-fifth compared with a conventional mechanical ball bearing. [ABSTRACT FROM PUBLISHER]

This paper considers the development of a new type of a magnetically driven diaphragm pump. The pump features small size, low energy consumption, and low noise. The pump model, the driving hardware circuits, and the control of the pump system are developed. The main characteristics of the pump are evaluated through several experimental results. The pump can be used in many medical applications like home oxygen concentrators for chronic obstructive pulmonary disease patients (COPD patients), rehabilitation machines, hemodialysis machines etc. [ABSTRACT FROM PUBLISHER]

Two types of absolute displacement sensors have been developed for vibration control. One is first-order differential type for the field of precise structure, and the other is second-order differential type for the field of large-scale structure. In particular, authors have proposed the former one to reduce amplifications of high frequency noises induced by twice differentiations. However, it is revealed that bandwidth of the proposed sensor is narrow to control leading-edge anti-vibration apparatuses. Therefore, this paper considers bandwidth expansion of the first-order differential type absolute displacement sensor in low frequency region. At first, dynamics of the displacement sensors are investigated based on root locus analysis. This is because the bandwidth expansion has a limitation due to high frequency resonance. Next, since there is trade-off between detection sensitivity and the bandwidth, the sensitivity is improved by detecting back electromotive forces from not only a calibration coil but also a forcer coil. Finally, the bandwidth of the proposed sensor is expanded in low frequency region, and results are shown in experiments. [ABSTRACT FROM PUBLISHER]

This paper presents a new modeling and controller design technique for the steel sheet processing line based on Hybrid Petri Nets (HPN), Mixed Logical Dynamical Systems (MLDS) expressions and system identification techniques for hybrid systems. In the steel sheet processing line, the dynamics of sheets is represented by differential equation. On the other hand, some operations such as welding of the steel sheets are described by logical formulas. HPN can harmoniously integrate these two different aspects. The HPN expression can be transformed into a suitable formulation for numerical optimization. Based on this modeling, the closed-loop control can be realized by receding horizon scheme. At the next step, control laws are extracted from the results obtained by receding horizon scheme. The method identifies probability weighted ARX (PrARX) functions as a controller. Some simulations are conducted to demonstrate that the identified controller can achieve fast and near-optimal control. [ABSTRACT FROM PUBLISHER]

Contactless power transfer is expected to be applied to many applications since it is convenience and safety. Inductive power transfer (IPT) is a kind of contactless power transfer schemes uses two coils. These coils are inductively coupled and power is transferred from primary coil to secondary coil when high frequency (a few tens of kHz) AC power supplies to primary coil. In many applications using IPT, received AC power is converted to DC power and then the power is charged to battery. Thus, two functions which are rectification and regulating voltage or current are required on the receiver (secondary) side. In this study, one of two types (buck type and boost type) of DC-DC converter connected to diode rectifier were applied to IPT system, and characteristics of each type were compared by experiments. As a result of the experiments, it was found that both rectifiers have two functions which are rectification and regulating voltage or current. It was also found that boost type is better in terms of regulation capability and of efficiency of resonant circuit. [ABSTRACT FROM PUBLISHER]

This paper describes a drive system of PM motor using Energy Harvesting. Thermoelectric elements are applied to PM Motor to generate small electric power that recovers the heat. Then, the heat of the motor is reduced, thermal demagnetization is resolved. This paper shows a proposed drive system and a drive circuit which is driven by generated small electric power. The system is evaluated by some experimental results. [ABSTRACT FROM PUBLISHER]

To overcome the limitations and the shortcomings of the existing single fault line detection algorithm in the neutral grounding system via arc-suppression coil (NES), a novel detection algorithm is outlined. After the respective analysis of the fault component criterion, the wavelet criterion, the active power criterion and the spectrum analysis criterion, the fuzzy theory is introduced and applied in the fault line detection to intelligently integrate all of the criteria on the single-phase-to-ground fault detection and fuse all of the fault information. The simulation results show that the proposed algorithm has high reliability. [ABSTRACT FROM PUBLISHER]

An alternative actuation system for fractionated spacecraft is to use electromagnetic force without the expenditure of fuel. This paper investigates the novel application of virtual rendezvous and docking for fractionated spacecraft with concepts such as wireless power transfer in mind. Firstly, the magnetic force model and relative motion dynamics are introduced. Then, the feedback control law for circular motion of electromagnetic system is presented, and the control scheme for virtual rendezvous and docking is also proposed. Finally, the numerical simulations are carried out. Simulation results verify that the proposed approach is feasible and effective. [ABSTRACT FROM PUBLISHER]

Nowadays multiple receiver coil systems are often used in magnetic resonance imaging. The sensitivity profiles of these coils are usually unknown and could be quite different so that the sum-of-squares (SoS) reconstruction algorithm can yield less desirable performance. In the previous research, a polynomial is used to iteratively fit the coil sensitivity profiles and the reconstruction performance is improved. We extend that algorithm by considering multi-stage reconstruction. More specifically, a lower order polynomial is used at the first stage when the noise is strong. After that, the noise has been efficiently attenuated and a higher order polynomial is used to better fit the coil sensitivity profiles. Experimental results confirm the efficiency of this multi-stage algorithm. [ABSTRACT FROM PUBLISHER]