The following outlines Speaker Recognition Technology, which identifies the individual by analyzing acoustic features of speech. Speech provides significant interface, being usable through the closest medium available, such as microphones and telephones (Requires no special equipment), and with small spatial restriction (Hands free ability). Usage of speech technology is not limited within security application, but is expected to provide more convenience, like preparing the best service to each user, or for limiting a voice command for use only by certain speakers. Given also are product examples : ANIMO's" VoiceGATE II" (Speaker Verification) and ANIMO's "VoiceSync" (Speaker Identification)

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This paper describes an authentication system which employs a dynamic signature of handwriting electronic signature for personal authentication. The dynamic signature verification system Cyber-SIGN is compared with existing authentication means on several characteristics and is described on basic method of verification. Several examples of actual applications as TCP/IP network application and/or standalone system are presented along with methods of implementation.

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Fingerprint matching has proved to be an effective technology for identifying persons, since it is highly accurate while the system can be inexpensive and compact. This paper covers the state-of-the-art of fingerprint-based personal identification, including principles and implementation of an input sensor and identification algorithms, system design and its applications. It also discusses and enhanced user interface "Fingerprint User Interface" that enables users to assign commands, data objects, or personalization settings to individual fingers for userfriendly direct manipulation.

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This paper describes two themes about biometric authentication techniques. Firstly, this paper describes a standardization of testing and evaluating for fingerprint verification. We had been commissioned to consider the standardization by the Information-technology promotion Agency (IPA) of Japan in 1999. The Standardization composites of two guidelines, (1) Guidelines for accuracy test, and (2) Guidelines for requirements decision. System-integrators and users can compare some vender's authentication products through these guidelines. Secondly, this paper presents a proposal of a personal authentication system via the open network by using a smart card including a fingerprint template with the digital signature such as X.509. We developed a prototype authentication system in where verification process is operated in the smart card. The proposed system can realize a high security and easy authentication on the public key infrastructure.

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A human face is one of biometric features, which carries their owner's personal information. People usually don't hide their faces on their daily life and it's easy to catch their features as images sensing devices without any contacts. These characteristics are preferred by wide-range applications, i.e. smooth man-machine communication, user-friendly security improvement, and so on. The art of human face identification technologies is only available under very limited circumstances and irregular face images easily make identification performance go down, because of the generally similar shapes of faces combined with the numerous variations between images of the same face. This paper categorizes origins of variations, and some results according to computerizable approaches against them are described.

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We have succeeded in developing two types of technologies about automatic facial recognition using Gabor Wavelet transformation and Graph Matching method. One is One-stop type to recognize the face when user shows his (her) face in front of CCD camera cooperatively. The other is Walk type to recognize the face who is walking non-cooperatively. Applying these technologies, we have developed two applications, Access Control System and Wandering Person Detection Support System.

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This paper describes a new input equipment of computer to use " Eye Gazing Detection Tecnology ". The method consists of four phases : (i) explaining about "Eye Gazing Detection Technology", (ii) explaining about our technology, (iii) how to develop a application, (iiii) samples of the application, Possible to demonstrate the application of using "Eye Gazing Detection Technology", It is only to connect our unit " TE-9101 Eye Behavior Interface Unit " with a computer. The result shows that we can use "Eye Gazing Detection Technology" as a new input equipment of computer, and it is a non-contact switch.

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The behavior of a rubber-covered roller and a rigid roller driving a loaded paper in transition from the sliding contact to the rolling contact are simulated by the finite element method. The shearing stress distribution and the deformation of the rubber as well as the local slippage in the contact arc are investigated by enforcing the rotating condition on the rubber-covered roller. The effect of the normal load, the tail force and driving configuration on the speed rations of the driving roller and the paper are studied by using the proposed mechanical model which based on the deformation mode and the micro-slip zone in the contact zone.

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The printing quality of the printer is influenced largely by the jitter. Although this jitter occurs by the various factor inside the apparatus, the biggest factor are the tooth profile error and backlash of the gear. The revolution variation of gear system is simulated by explicit dynamics finite element program and the jitter is calculated from revolution variation. The practicality to estimate the influence to the jitter by the tooth profile error and backlash for designing the gear system is confirmed.

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A mechanism for correcting the skew of a without-feed-hole paper fed into a high-speed laser printer has been developed. Our skew correction mechanism changed the load balance of the feed roller according to the paper position detected by an optical sensor. We have experimentally studied the relationship between the load of the feed roller and paper speed. Skew correction control parameters were obtained by these data. We showed that this mechanism can feed a paper accurately regardless of its width.

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This paper discusses dynamic frictional forces of the rubber roller for the paper feed mechanism which handles copy papers, bills and so on. The measurement of frictional forces between rotating rubber rollers and a paper under the condition of practical paper feed mechanism demonstrates that the frictional forces strongly depends on the feed velocity and the temperature. Therefore, the new feed mechanism, called GRR type mechanism which does not based on the difference of the frictional forces are proposed.

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A paper feeding system with rubber rollers is widely used in an information processing equipment such as a copy machine and FAX, ATM. In order to control the paper velocity, it is important in its design to estimate the effect of normal force and back tension on the velocity ratio of paper to roller rotation. We propose a new model on the paper motion and the contact mechanics in friction drives with rubber rollers. It describes the velocity ratio by using the deformation and micro-slip between the rubber roller and the paper which are calculated with FEA.

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This paper reports on the resonance controls of a suspension used for a magnetic Hard-Disk Drive (HDD). First, the control method of torsion mode gain, induced by shaking, is described. Secondly, the control method of torsion mode suspension flutter, induced by air turbulence, is described. The mechanism of first torsion suspension flutter was investigated, and the evaluation method by calculations was proposed. Finally, a new type of suspension using two separate parts for the loadbeam was designed. The evaluation results of the actual samples agreed with the calculated values. The new design achieved considerably high performance of suspension flutter characteristics with very high resonance frequency of first torsion mode.

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Aiming at an ultra-high area density over 100 Gbits/in^2 reduction of magnetic spacing will become very important for hard disk systems. one solution is a full contact recording system. However, contact sliding induces large friction, bouncing and abrasion. In this paper, we measure dynamic phenomenon of single beam suspension of two types of slider that was on a lubricated rotary disk surface. The single beam with a ball slider indicated stable contact at the early stage of the test. But, Rubricate film soon breaks and bouncing of the beam occurred. The single beam with a flat slider causes stick-slip and vibration. However, since the flat slider has many contact points the lubricant film does not break, hence stable contact sliding continues without any fluctuation. Dumping effect and meniscus force of the lubricant are keys to suppress slider bouncing. It may be thought that requirements for the lubricant may be a rather high viscosity for the ball slider, anti-stick properties for the flat slider.

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The dynamic behavior of pico sliders is investigated during head/disk contacts as a function of velocity, pitch angle, crown height and lubricant thickness using laser Doppler vibrometry and acoustic emission sensors. Analog and digital filtering methods are applied to distinguish air bearing and slider body resonances from frequencies related to disk runout, load beam design and gimbal structure. Sliders with high pitch angle and small crown were found to exhibit smaller vibration amplitudes after slider-disk contacts than sliders with low pitch angle or large crown. The lubricant thickness of the disk was found to affect both the glide avalanche height of the disk and they dynamic behavior of the slider. The results show that roll and pitch frequencies of the airs bearing increase with decreasing disk velocity.

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We numerically analyzed the bouncing vibrations of two-degree-of-freedom (2-DOF) model a tripad contact slider with air bearing pads over a random wavy surface and manifested design conditions of a contact slider. As a result, we found that friction force decreases contact sliding ability at the boundary of intermittent and continuous contact sliding. We also found that the distance between the rear air bearing center and the contact pad has a significant effect on the contact sliding ability. Based on the analytical study, we proposed the two design concepts : 1) Make the distance between the rear air bearing center and the contact pad be as small as possible. In this case, the larger rear air bearing stiffness results in the better contact ability. 2) If some distance between the rear air bearing center and the contact pad is inevitable, make the rear air bearing stiffness much small than the contact stiffness.

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Computer simulation of bouncing vibration and wear characteristics of an in-contact head slider was performed using 3-degrees-of-freedom (3-DOF) model of a head-suspension assembly, considering the meniscus force generated by the surface energy of the lubricant on the magnetic disk. As a result of the calculation, it was found that a optimal surface energy for design of the contact head/disk interface system could be obtained by the simulation. It was pointed out that the 3-DOF model was more advantageous than the 1-DOF or 2-DOF model to obtain the dynamic characteristics of the in-contact head slider.

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The rapid advance of the digital network systems requires storage devices with higher densities and faster transfer rates. These requirements also accelerate the advent of ultra-high-density optical data storage. From this perspective, near-field recording technology is thought to be one of the promising breakthroughs to overcome both the tough diffraction limit and the wavelength-shortening limit. We propose a novel optical head assembly based on flying head slider and flexible optical guide circuit technology. A carefully fabricated optical guide successfully works as a flexure, which suspends a silicon optical slider with an extremely small pyramidal aperture. Measured mechanical characteristics agree well with numerical predictions utilizing FEM structural analysis combined with thin film gas-lubrication analysis. Moreover, we try microscopic optical analysis on the pyramidal aperture based on the Maxwell Equation and the finite-difference time-domain algorithm.

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We used a high-speed video camera to observe the behavior of sliders in a 3.5-inch drive (contact-start-stop system) that was subjected to an external shock. The observation showed that the sliders jump most easily when the magnitude of the shock pulse is large and its duration time is short. We also investigated the jumping phenomena by measurement and FEM analysis. The FEM results show that the slider jumps when the inertia force of the slider, due to the vibration after the external shock, exceeds the load applied to the slider. And it is concluded that the influence of the vibration of the guide arm on the inertia force is lager when the duration time is shorter.

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Small oil particles generated from lubricant of rolling bearings in HDD sometimes cause such a fatal problem as disk crash. Therefore, a labyrinth seal is often used in HDD in order to prevent oil particles from scattering on the disk surface. In this paper, the seal performance of small oil particles of an annular labyrinth seal is investigated, numerically and experimentally. It was consequently found that the annular labyrinth seal is very effective in sealing small oil particles of more than 0.3 μm diameter.

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Fabrication process of micro electro magnetic motor has been developed. Multi-layered coils and flexible wiring patterns are formed on a silicon substrate using the semiconductor processing technique. After coils are made, the substrate is removed by etching from the reverse side to obtain a sheet on which multi-layered coils have been formed. Core pieces are made by wire-cut electric discharge machining, and the flexible sheet with coils is wound around core pieces. A 2-pole magnetized permanent magnet is separately fabricated as a rotor Using this process, a prototype micro-motor 1.6 mm in diameter was fabricated and the output power of 3.2×(10)^<-7> Nm was obtained.

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In this paper, studies on silicon carbide (SiC) micromachining and micromachined gas turbines are described : (1) SiC micro-reaction-sintering combined with silicon lost mold method has been developed, and SiC micro-rotors of 5 and 10 mm in diameter were fabricated. (2) Deep reactive ion etching (deep-RIE) of sintered SiC is being studied. To date, the etching depth of over 100 μm was achieved at the speed of 0.48 μ/min. using an inductively coupled plasma RIE system with SF_6 gas. (3) Silicon micro-air turbines for rotating an integrated grid polarizer have been fabricated, and the rotational speed of about 10000 rpm was achieved. (4) A computer fluid dynamics (CFD) program is under development for numerical fluid analysis inside micro-gas turbines. The airflow inside the abovementioned micro-air turbine was 2-dimensionally calculated.

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We measured the average power of thin linear-driven generators for use in card-type mobile communication terminals, which produce electricity from mechanical movement. A Long Voice Coil Generator driven by free fall energy, stroke length : 30 mm , yoke width : 120 mm, and thickness : 12 mm generates 6.7 mW with efficiency of 51%. A cellular phone sized-Voice Coil Generator driven by free fall energy and a spring, stroke length : 50 mm , yoke width : 20 mm, thickness : 12 mm generates 9.6 mW with efficiency of 32%.

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This paper is about an electronically controlled mechanical watch that has an electronic regulator in place of the usual mechanical regulator. This electronic regulator consists of a generator, a rectifying circuit, a control circuit, and a crystal oscillator. While conventional mechanical watches are accurate to within 10 to 20 seconds per day, a mechanical watch with an electronic regulator is accurate to within one second per day. There are two points in the development of the electronic regulator. The first point is the development of a generator and a rectifying circuit that can efficiently convert mechanical energy from the barrel into electrical energy. The second point is the development of a control circuit that keeps generating electricity while the magnetic brake is applied.

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Micro thermoelectric generator has been developed and applied to energy source of a thermoelectric wristwatch. Developed generator chip is consisted of 378 pairs of BiTe thermocouples in size of 6.1(mm)^*2.7(mm)^*2mm. 6 chips of generator is arranged around a movement of watch and generate about 1V taking temperature difference between metal case and case back. That voltage is enough to drive a watch and average generation energy of 12μ W was estimated from wearing experiments of watch.

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This study was conducted to develop applications using CoFeSiB/SiO_2 composite multilayer film with a high quality factor of more than 100. It is necessary that the efficiency of the micro DC・DC converter be increased by incorporating a high quality factor inductor capable to minimizing the generation of heat due to magnetic loss. The terms for high Q values of inductors depend on both low iron loss of magnetic thin film cores and low copper loss of air coils. We have developed high Qind herical coil inductor of more than 50 using these composite multilayere film. The maximum value is obtained at the frequency of about 40MHz &acd; 50MHz. To attain the optimum micro-power supply, it is necessary to use a high Q inductor which has a low loss magnetic core and an air core.

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This paper describes thin film inductor using nano-crystalline Fe-Zr-O thin film. Nano-crystalline Fe-Zr-O film has a low loss at a high frequency because of its high electrical resistivity, ρ of 1000μ Ωcm. Furthermore, Fe-Zr-O has good soft magnetic properties, which are 46A/m of coercive force, Hc, 1000 of permeability, μ', 1.24T of saturation magnetization, Is. It is possible to keep eddy current loss down up to MHz range to use nano-crystalline Fe-Zr-O thin film. Therefore, the thin film inductor using nano-crystalline Fe-Zr-O thin film shows high quality factor, Q over 8 at MHz range. DC-DC converter using thin film inductor exhibits high efficiency, η of 80% in the buck converter.

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We have successfully fabricated a thin-film flux-gate magnetic sensor (TFG sensor) on a 2.6mm square chip utilizing photofabrication technique, and a compact hybrid-integrated-circuit (HIC) driver for this TFG sensor. The sensor consists of a permalloy ring core, an excitation coil, and a differential pickup coil. The TFG sensor and the driver have been downsized, in order to expand their field of applications. We have also developed a "bi-axis TFG", which has two sensing axes meeting at right angle with each other and which is yet of the same size as the conventional "mono-axis TFG". The resolution for magnetic flux density of the TFG sensor is below 50nT, and the magnetic sensitivities of the mono-axis TFG and bi-axis TFG are 30mV/μT and 39mV/μT respectively. Excellent output linearity (0.2%f.s.) is ensured for magnetic flux density in the range from -100μT to 100μT.

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Research on the use of the card-type non-contact power-supply system as a powering device for the card-type portable equipment is continuing. We have developed a new transmitting coil unit that uses a Co-based amorphous ribbon instead of a ferrite substrate. This new coil unit is thin yet very flexible. The coil unit has allowed us to use a thinner card. The new unit stacks up to three 25-μm-thick ribbons, having a half of thickness of the previous unit while maintaining the same electrical characteristics.

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We design small magnetic AC markers and investigate its external magnetic field around a marker. We fabricate several AC markers (12.5mm-length, cross sectional are of marker was 15(mm)^2). Measured field of markers is agreed with theoretical field calculated by Biot-Savart's low. External field was about (10)^<-3> Oe, when we applied 1.5V at 425kHz and the distance between marker and sensor was 100mm.

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Fine motion characteristic is very important for precision positioning systems because positioning accuracy and positioning time depend on the characteristic. The fine motion characteristic is greatly influenced by the characteristics of the mechanism. Non-contact mechanisms using pressurized air films or magnetic force have very good fine motion characteristic because they have no friction element and backlash. However the non-contact mechanisms make the positioning systems large and expensive, and have small load capacity. In this paper, three kinds of precision positioning methods which do not require non-contact type mechanisms, (1) utilizing the nonlinear spring characteristic of the mechanism, (2) improving the fine driving characteristics by using fine motion actuator and (3) utilizing dynamics in microworld and micromachining technique, are introduced. These methods have different features. So it is important to choose a suitable method for the application

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Polymer microfabrication methods are becoming increasingly important as low-cost alternatives to the silicon or glass-based MEMS technologies. This paper describes a new process suitable for fabrication of micro periodic structure in optical waveguide. Si mold were fabricated using electron beam lithography and fast atom beam etching. Grating coupler were fabricated by replication of polymers using the mold. The grating coupler was evaluated with a monochromator.

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This paper reports a multi-mode micro-mechanical optical switch whose actuating mechanism is based on thermally induced capillary action. We propose novel fabrication processes for integrating the thermo-capillary optical switch into a polymer-based waveguide, and demonstrate its driving action. Noting that Ti has resistance against oxygen gas, we used O_2 RIE with Ti mask to form a slit with a high aspect ratio of 10. We have developed a technique for planarizing the upper cladding just by applying a polymer coating without polishing. Therefore we could drastically reduce the fabrication time. We hermetically sealed the slit by thermal lamination at a temperature below the glass transition temperature (Tg). We formed an oil column with a small volume using an oil injection method, which we developed. The switch element performed both switching and latching actions successfully, confirming the basic operations of the switch.

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The purpose of this research is to establish the self-alignment technique for the microparts assembly using liquid surface tension, which can use widely. For this purpose, we have proposed the following self-alignment method using the microparts of which surface is divided into two kinds of areas, that is, the wettability of one area is higher than that of the other : (1) first, a drop of liquid is put on high wettablity surface area of the first part, (2) next, the second part is put on the first one, (3) and then the second part is moved by the surface tension of the liquid so that the wettability area pattern of the first part overlaps with that of the second one, (4) finally, the alignment is accomplished. In this paper, first, the behavior of microparts and liquid in the alignment are examined experimentally and theoretecally. And then the relationship between the behavior and the alignmnent accuracy is discussed.

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As a simple manufacturing method for high-precision micro-spherical bearing, the micro forming technique of metallic glass was applied. Metallic glasses are amorphous alloys with the wide supercooled liquid region. Those exhibit amorphous alloy's characteristics at room temperature. Moreover, in the supercooled liquid state, its viscosity is as low as that of a heated conventional glass. In this study, a Zr based metallic glass (Zr_<55>Cu_<30>Al_<10>Ni_5) which equal stainless steel in the strength at room temperature was used. The micro spherical bearings were formed from a polished steel ball of the 3mm diameter as die in the supercooled liquid state. The profile error of the formed bearings was less than 3μm and the Vickers hardness, Hv 545 or more.

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A new position sensing system, which is composed of a 2-D angle gril and a 2-D angular sensor, is proposed. The angle grid has a 2-D angular information pattern on the surface. The relative displacements between the angle grid and the angular sensor in the X and Y directions can be detected from the output of the angular sensor. Furthermore, use of an optical scanning angular sensor, which can scan a beam spot on the angle grid, can reduce the effect of the form error of the angle grid. Using constant speed scanning, the scale of the angle grid can be interpolated from time scale. In this paper, a signal processing system utilizing high-speed pulse generation and count circuits is designed to achieve high speed position detection. The experimental result of this position detection is reported.

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This paper describes a three-dimensional position detecting method that uses a photoelectric sensor for precise positioning of a robot hand. The output of the sensor is proportional to the power of the light reflected by a target. Therefore it changes according to the position of the target. In detecting the X position, the robot hand that is gripping the target scans in the X direction in front of the fixed sensor. The position of the sensor can be detected using the relation between the position of the target and sensor output. In detecting the Y and Z positions, the hand scans in the Y and Z direction in the same way it does for the X detection. The deviation error caused by the difference of the scanning position is less than 50μm, which confirms the feasibility of our position detecting method.

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A new decoupled track-seeking controller methodoloty is proposed for dual-stage servo systems of magnetic disk drives. The controller is applied to the dual-stage system with a push-pull PZT micro-actuator and enables high speed one track-seeking. The methodology has three steps design procedure : 1) Design a VCM feedforward controller to prevent overshoot in response of VCM actuator. 2) Design a feedforward loop from the VCM reference signal to the PZT actuator, such that an output PES (position error signal) only follows a PES reference signal. The robustness of the seek controller for both gain variation and PZT hysteresis is analyzed by using simulations. Simulations and experiments show that the proposed dual-stage track-seeking controller is a more effective performance than the conventional single VCM servo and can achieve 0.3ms one-track seeking time.

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This paper describes two types of head positioning mechanism of hard disk drive. Stabilized positioning mechanism consists of a conventional swing-arm positioning mechanism and a minor-loop analog feedback controller. This controller utilizes estimated velocity of main out-of-phase vibration mode and the estimator needs only VCM voltage and current signal which are easily measured in the circuit. In-phase positioning mechanism consists of an in-phase swing-arm positioning mechanism that was proposed by us. Characteristics of proposed positionig mechanisms are shown by simulation and experimental results.

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Accurate servo track writer (STW) is indispensable for hard disk drives (HDDs) with high track density. We have developed a prototype of the Hybrid-type STW, which consists of two writing stages. In the first stage, master patterns are written on one surface of the master disk prior to drive assembly. In the second stage, the master disk is assembled with several raw disks in a HDD, and the servo patterns are written on the disks on the basis of the master patterns. This paper describes the design of servo system for the Hybrid-type STW and experimental results using a 2.5 type HDD. One of our results is that in comparison with the conventional STW, the Hybrid-type STW can suppress low frequency vibrations of ball bearings and reduce the maximum value of repeatable runout (RRO).

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This paper considers the determination of reference trajectories for use with a two-degree-of-freedom (2-DOF) controller for the head positioning of Hard Disk Drives (HDDs). The reference HDD model used for the design includes the back e.m.f. (electromotive force) of the voice coil motor. In the second stage, the idea of SMART (Structure vibration Minimized AcceleRation Trajectory) is utilized to adjust the errors at the end of the trajectories. 2-DOF control with the proposed reference trajectory is compared to conventional mode switching control, and its effectiveness is verified. To minimize performance degradation due to disturbances and uncertainties, the use of Adaptive Robust Control (ARC) is suggested.

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This paper discussed the design and experimental verification of a new digital position control method for a high-speed optical disc drive. The position control method needs to improve disturbance suppression capability, as the disc rotation speed becomes higher. We apply a repetition compensator in order to reduce repeatable position error. The control system is implemented in an optical disc drive set-up. The optical disc can rotate at speed of 9000rpm and its sampling frequency is 176kHz. The experimental results that the proposed repetition compensator with 5th order compensator can reduce both the focus and the tracking error caused by the disc disturbances.

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For demands of high-density recording with a high data transfer rate, various recording head shapes were designed to achieve the low tape surfacing. The momentum equation for a tape of finite length is coupled to the transient lubrication equation for the air film between the tape and the recording head. If ditches exist on the recording head, it is necessary to use the fluid equations. In this paper, we introduce an analysis approach with connecting the fluid equations in a ditch and the lubrication equation in narrow space by these boundaries.

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A Michelson interferometer based on the Linnik microscope configuration has been constituted and applied to the measurements of lubricant spreading on magnetic disk surfaces. Using image processing on the fringe patterns formed by the interferometer, the spreading behaviors of lubricant films can be investigated by measuring the thickness profiles of the films. This method provides complete line profiles in two dimensions and permits direct observation of spreading phenomena, in contrast to conventional point-by-point scanning method. A fringe following technique and a noise suppression technique were introduced to improve the measurement accuracy. A novel scheme was proposed to give maximum measurement sensitivity.

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Accurate and high speed estimation method of pressure flow factors for ultra thin spacings with surface roughnesses using DSMC (Direct Simulation Monte Carlo) technique is proposed as hydrodynamic air bearing problems. The 2-dimensional pressure flow factors for parallel flat plates calculated by the method give good agreement with the value obtained by the linearized Boltzmann equation based on hard sphere model and BGK model.

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The numerical simulations for load/unload process is investigated. In this simulation, the generalized lubrication equation based on the linearized Boltzmann equation and the suspension motion equation are solved simultaneously in the time domain. The suspension is modeled as lumped vibration system. To simulate contact condition of the suspension motion during unload process, the suspension model consists of 4 status depend on the contact conditions of tab, dimple and limiter. Each status has different stiffness and mass matrix calculated by FEM analysis. The unload behavior for 2.5 inch type drive is calculated with 3 unload speeds and 3 ramp heights. As unload speed increases, it needs larger unload force to peel the slider from disk surface. The roll balance of the air bearing force during unloading is very important to avoid slider-disk contact.

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