In this paper, we propose an innovative fluid transport system for μTAS. In this system, microchannels fabricated on silicon chips have active wall of a piezoelectric thin film directly deposited by sputtering on the outside of the microchannels. The active microchannel can transport the fluid by traveling wave induced on the surface of the piezoelectric moving wall by applying sinusoidal voltages to each patterned top electrode with different phase. Since the active microchannel was fabricated by micromachining process and has simple structure without valves and diffuser, it can be applied to μTAS without occupied area. The fluid transport system can be driven by low electric voltage, and integrated with intricate network design.

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In this paper, we propose micro electric power generation device. The device is fabricated by MEMS technique. PZT film is deposited onto a Si cantilever by magnetron RF sputtering. Electric power is generated when the cantilever is bended and stressed. The cantilever has 1200μm in length, 600μm in width, and 50μm in thickness. The device can convert mechanical vibration energy into electric energy. Good crystalline orientation was needed for high piezoelectric property. We analyzed the crystalline orientation of PZT by XRD, and decided the adequate deposition condition. The device generated electric power about 1pW.

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Piezoelectric deformable mirror for adaptive optics is studied as an adaptive optics device. We have studied the piezoelectric mirror which have 19 upper electrodes. To improve the accuracy of the deformable mirror, we designed two upper electrode types, hexagonal electrodes 37ch and coaxial electrodes 35ch. To compare two electrode types, we calculated deflection of the designed mirrors by using Finite Element Method analysis simulation software, MSC. Marc. Zernike polynomials are used to evaluate the mirror surface, and the control system is based on the influence functions for generating Zernike modes. To compared with three electrodes types, 37ch, 35ch and 19ch, the residual RMS of hexagonal electrodes 37ch was the smallest, less than 0.005μm.

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To make micro parts such as some micro optical devices, bio devices and so on cheaply and massively, a micro forging of resin using micro dies is an advantage producing technique. Required performances of the micro die are high precision, surface roughness of nano order and the resistances of corrosion, high pressure and high temperature. Thus, we proposed a micro die of titanium superplastic alloy, SP700, and covered with a hard coat of titanium nitride, and have studied on the fabrication technique by superplastic forging of the alloy using a silicon master structure and by simultaneous diffusion bonding of functionally gradient layer of TiN/Ti with the Ti alloy.

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We proposed a new micro actuator made of elastomer and a magnetic material. It could be activated by an applied magnetic field without electric wiring Theoretical formulation for the present micro actuator is expressed, which shows that the micro actuator could work even though it became nanoscopic scale. We demonstrate experimentally that deformation of our actuator is distinctive, and also discuss how to design the initial structure to obtain desired deformation pattern by computational method.

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Biodegradable polymer is key material for realizing a sustainable society. It is also useful for making minimally invasive surgical devices that resolve in the body. Although micro mechanical structures of biodegradable polymer are needed, few micromachining processes were reported. We proposed and developed precise etching method of Poly (L-Lactide), one of the biodegradable polymers, by using oxygen reactive ion etching and flexible stencil mask that was made of polyimide film. This etching method does not damage the polymer because of low temperature process and the use of mild organic solvents. Etching characteristics and process condition were investigated. Maximum and minimum etching errors were 15μm and 1μm, respectively.

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This paper presents an overview of the Moving-mask UV (ultraviolet) lithography technique and a photoresist profile simulation for the Moving-mask UV lithography using a positive-tone thick photoresist. In order to realize a wide variety of 3-D (three-dimensional) microstructures, the developed proximity 3-D UV lithography apparatus adopts the "moving-mask lithography" concept. Furthermore, we propose a practical photoresist profile simulation approach adopting the "Fast Marching Method" to consider the photoresist dissolution vector in the development process. The proposed approach deals with two important factors to control 3-D thick photoresist profile: the effect of UV light diffraction and non-uniform photoresist properties along thickness direction. Through moving-mask UV lithography experiments, (1) the capability of the moving-mask UV lithography for 3-D microstructuring, and (2) the validity of the proposed photoresist profile simulation, were successfully confirmed.

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In order to measure the pressure and the temperature of a contact between surfaces under a sliding-rolling contact condition, it was tried to develop a thin film sensor using MEMS (Micro Electromechanical Systems) process technology. In this paper, a contact pressure sensor was manufactured by lift-off method. The sensor consists mainly of thin wires made of palladium and a thin polyimide film. The performance of the sensor was investigated using a compression testing machine and a Wheatstone bridge circuit. The output voltage of the sensor raised as the compressive load increased. However, the output voltage of the sensor was not stable, as the sensor width became smaller.

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A design of the micro-scaled tactile sensor which consists of two springs for Minimal Invasive Surgery was investigated. The sensing principle is based on the concept of applying two springs of considerably different stiffness to soft tissue for compliance detection, which reading is independent on the applied displacement between the sensor and tissue. Finite Element Method (FEM) is used to study the effect of tip shape (sphere, cubic) and the distance (0.5, 0.6, 0.7, 0.8mm) between the tips for the sensor with spring constants of 4500N/m and 110N/m under tissue Young's modulus of 0.3, 0.5, 1.0MPa. The results showed the cubic tip shape possesses independent reading on the pushing distance rather than the spherical one. The distance between the two springs of larger than 0.7mm is necessary to avoid the cross-talk effect between two spring behaviors.

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We have developed a method of resist patterning using a knife edge probe for fabrication of narrow gap comb-drive actuators. According to a theoretical formulation of a comb-drive actuator, the gap between both opposing comb electrodes strongly affects its electrical property, especially Q-factor. An equivalent circuit of the comb-drive actuator was also conducted to evaluate effects of the gap. The patterning was done by AFM in which a photo resist layer was carved by a knife edge probe. The fabricated pattern was then transformed to an aluminum layer which was used for a mask of Si ethicng. Using this method we have obtained very small trench structure having 460nm in width and established aspect ratio of more than 50.

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This paper describes biomimetic water strider robots with microfabricated hydrophobic legs. Various kinds of supporting legs with hydrophobic microstructures on their surfaces were developed using MEMS (microelectromechanical systems) techniques. Lift force of the legs were investigated both theoretically and experimentally. The experimental results are in good agreement with the calculations. Furthermore, two different mechanisms for autonomous water strider robots have been developed. The robot with twelve microfabricated legs driven by a vibration motor successfully moved on water surface and also made left/right turns utilizing difference of resonant frequencies of the legs. The other robot with six microstructured legs also successfully moved on water by creating elliptical motions of the middle legs, which is similar to the motions of water strider's legs.

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Novel self-assembly process using electrostatic adhesion energy induced by contact electrification phenomenon is proposed for the first time. The contact electrification, which is observed when two different metals, such as platinum (Pt)-Silver (Ag) are contacted, was utilized to align a face of a component on a substrate. Two types of 1mm square silicon components with thickness of 0.5mm coated with Pt or Ag and Pt substrate were prepared. Adhesion energies for two different metal pairs (Pt-Ag and Pt-Pt) were measured by measuring the vibration energy to separate the components from the vibrating substrate. The experimental results indicated the adhesion energy between Pt-Pt was 0.57nJ, and Pt-Ag was 1.4nJ on an average. Secondly, the face alignment experiment was carried out by vibrating the substrate on which 20 components with thickness of 0.2mm were placed. The front and back face of the components were coated with Pt and Ag, respectively and they were split into half of Pt face up and the other half of Ag face up. Finally, we could get 83% components were aligned as Pt face up.

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Recently, μ-TAS have been attracted constant attention. In the case of antigen-antibody reaction, concentration of particle effects on detection sensitivity and reaction in near-wall of microchannel. As effect of van der Waals force and electrostatic force is large, lift force acted to particle is neglected. In this paper, effect of flow on concentration of particle in micro-channel was measured. Evanescent wave was used for observation of particle. Change in the lift force acted to particle was measured and the effect of the lift force on the concentration of the particle in near-wall. The results show that as the velocity gradient increases, the peak position of concentration of particle has parted from near-wall.

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To evaluate the influence of miniaturization on resonance characteristics of extertnally driven micropumps, the modal analyses for systems consisted of an actuator and microchannel including water was carried out. Scale factor defined in this paper quantified the influence of miniaturizing. When a cantilever-typed actuator was miniaturized, it became clear that the oscillation at a high resonant frequency negatively influence on the pump performance (especially when the scale factor is larger than 100 m-1). The influence of additional mass effect of water was negligible for the scale range in this study. When thin-film actuator was used, negative effect observed in cantilever actuator was not emerged. However, additional mass effect of water produced up to a 67% decrease in resonant frequency. We pointed out the necessity to take the additional mass effect of water into consideration when pump is designed.

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Recently, studies of positional relationships of cells are seemed to be very important for cell biology. We proposed a novel concept that self-organized vasculature integrate artificial orifices on a device. Using SIMPLE (Single Mask inclined Photo-Lithography Exposure) process, it is easy to fabricate embedded channels with orifices. Endothelial cells have a characteristic property that they organize vasculature by their selves in collagen gel. HUVEC (Human Umbilical Vein Endothelial Cells) are cultured on device for about 10 days in matrigel and artificial vasculature were immobilized on orifices by self-organized.

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Drag reduction of laminar flow in microchannel is very important for μ-TAS (Micro Total Analysis Systems). Ceramic substrates which consist of alumina particles have rough surface and it is used as a mold to fabricate PDMS rectangular channel with textured wall. Roughness of the wall is depended on diameter of alumina particles. Velocity profile of laminar flow in a textured channel is measured by micro PIV. The measurements reveal that reduction in textured channel can be achieved relative to the classical smooth channel Stokes flow.

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Recently, applications of medical devices are developed by combination of between medical science and engineering technology. Materials of medical devices must be studied for adsorption of proteins as bio-material. In this research, we study about proteins adsorption affected by metallic surface properties. Making metal membrane on glass plate and observing with evanescent light are used to study proteins adsorption on metal surface. In this time, we observed nano-particels adsorption on titanium membrane surface with evanescent light. The result showed that it was dependent on surface roughness of metal membrane.

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For analysis of cell-cell interactions, we have proposed a microchip fabricated by SIngle-Mask inclined UV Photo Lithography for Embedded network (SIMPLE process). The microchip is made of thick negative photoresist SU-8. In this study, we carried out the toxicity and proliferative tests of SU-8 to pancreatic islet β cell, MIN6. Then, the validity of the proposed device was confirmed by a suction test for MIN6 cells using the fabricated device.

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This paper describes a method for cell sorting using ultrasonic radiation pressure. In previous research literature, we proposed resin-based device that was superior to silicon-based device in the points of optical transparency and simple process. In this paper, we studied some phenomena different from the silicon device. The sound wave reflectivity of SU-8 is smaller than that of silicon. So first, we verified the influence of the wall using PDMS microchannel which had small reflectivity of sound wave. Then we verified the influence of whole device resonance frequency.

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In this paper, the concept and experimental results of Microwave-powered silicon microsensors for distributed and embedded sensing applications are presented. This is the first report of a microsensor device integrated with RF-DC power converter on the same chip. The integrated sensors are fabricated by silicon-MEMS technology. This time, 'fuse-type strain detector' was fabricated by silicon micromachining. Driving power of the integrated microsensors is provided as a remote RF-electromagnetic wave at 1.29GHz and received at the rectenna circuit on the microsensor. In the fabrication step, high-performance Surface Mount Devices (SMD) are integrated on the silicon microchip to realize the highest power efficiency. Mount holes of SMDs were formed by Deep-RIE of silicon with MEMS sensor structures without any additional process steps. Fabricated rectenna and sensors are successfully evaluated with LED mounted for signal output.

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Image shape of path and image motion of optical flow are two different types of critical visual information for drivers. As for information of path, Land and Horwood (1995) reported that drivers utilize far point of their path for finding future direction as well as near point for controlling current position of the vehicle. We investigated the effect of optical flow in addition to the effects of near and far points of path on the driver's performance using a driving simulator. In results, though the optical flow in far depth contributed to comprehension of driving direction and decreased drivers' load, the optical flow in near depth made their steering inaccurate. Based on these findings, we developed a new device to decrease visual disturbance in near optical flow, and applied it on an actual car. We found that the device improved the driver's head stability and steering stability. Thus, it is suggested that we can improve driver's performance by controlling visual information.

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The collaboration of monitoring robot and UFAM (Ubiquitous Functions Activate Module) is proposed to achieve automated, wide-range applicable, precise, speedy, and cost-low monitoring and inspection systems. UFAM is a module which provides wirless communication and control function to instruments existing in a great variety of environment. Mobile robots provide for a wide range and flexible monitoring for various situations by its mobility. By the characteristics of UFAM and the mobile robot, each monitoring error can be checked. The experimental results show the feasibility and efficiency of the proposed collaborative monitoring system.

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Traffic accidents at junctions or crosses occur often when the view of drivers is obstructed by walls. A system to find the approach of other cars by image processing is proposed. The image is taken by a camera attached at the nose of a car. The difference image of an image and the other taken after a short time is calculated. The first method is to measure the increase of the area of the car difference image. The second method is to measure the movement of the CM of the car difference image. It is verified by experiments using a model car that the both methods are effective.

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A concept of microfactory was proposed in 1990. The first R & D project on the microfactory was started by MITI in 1994. Mechanical Engineering Laboratory developed microlathe in 1996. After that, various R & D about the microfactory were carried out in public research institutions, universities and private companies. The International Workshop on Micro Factory (IWMF) was held in alternate years from 1998. This report describes these R & D, and views the future trend of the microfactory.

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On-demand manufacturing system for metal-based MEMS has been developed in trial. The system is composed by serial connection of several unit process cells. Each cell has its own process, such as punching press, Aerosol Deposition (AD) for ceramics coating, heat treatment and ink-jet wiring print. In the punching process, the divided progressive micro-press machine fabricates MEMS-like micro-mirror structure made of stainless steel. The processed part is fed to next AD cell; PZT ceramics actuator element is molded by AD process. After post processes of annealing, wiring and polarizing, the mirror device is completed, and it shows the performance better than one made of single crystal silicon. The system feeds one part step by step in single line, so it is better to control amount of product, compare to batch process system used in ordinary MEMS process. The developed setup does not only proof the ability of lower cost and higher flexibility as a manufacturing system, but also gets better performance as MEMS-like scanner mirror device.

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We are developing micro assembly machines that assemble MEMS components or optical parts with 1μm positioning accuracy. We report the basic design considerations of our micro assembly machine, and also shows some of the trials to the further step toward the better positioning accuracy.

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In order to clarify the behavior under micro cutting conditions, we have performed cutting of aluminum alloy and free machining brass using the high-speed micro-spindle. The results of the experiment shows that surface roughness has been improved under the conditions of high rotation speed and low feed rate. These conditions mean that an area of chip section is small. Cutting resistance force increases in proportion to the-increase in an area of chip section, although dispersion is large. These results indicate that the specific cutting force becomes remarkably large when an area of chip section becomes small at high rotation speed.

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An optical measuring device for measurements of radial error motions of miniature ultra-high-speedr spindles has been developed. It is essential to measure the radial error motion of the miniature ultra-high-speed spindle in order to verify the machining accuracy of the miniature machine tool. The optical measuring device is based on laser auto-collimation and uses a small steel ball, mounted on to the miniature ultra-high-speed spindle, as a reflector. This paper describes the configuration and the measurement principle of the developed device and shows some of the measurement data of the radial error motion and the analysis results.

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The final goal of this research is to develop a condenser type micro ultrasonic sensor, which would be used as both receiver and transmitter. Polymer diaphragm is flexible and non-brittle, allowing good sensitivity and durability. Besides that, Parylene has good C-MOS compatibility, since it can be deposited at room temperature. Based on the FEM simulation results on the resonant frequency under tensile stress of Parylene, the diaphragm radius of 500〜1200μm is employed to realize the bandwidth up to ultrasonic range of 40〜100kHz. The influence of the number and the radius of acoustic holes on damping ratio is investigated by FEM simulation, in order to achieve a moderate damping of the diaphragm. Practical sensor devices are fabricated. They can receive an impulsive ultrasonic pulse transmitted by a spark discharge. The open-circuit sensitivity is 0.3mV/Pa, in reference to B&K 4138 microphone. The ranging system using this sensor can detect the distance up to 1m with the error less than 1mm. The developed sensor can be approximated to be non-directional.

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Authors have already reported a micro accelerometer made of Parylene, which comprises a proof mass and support beams. The measurement principle is detecting capacitance change according to dielectric mass movement in a fringe electrical field. Owing to low dielectric constant of Parylene (ε_r=3.15), the sensitivity is comparatively low at present state. This paper newly proposes an accelerometer using ferroelectric material having large dielectric constant such as bulk PZT (ε_r=2600) instead of Parylene. Since micromachining of suspended structure of bulk PZT is difficult, it is used as a substrate. It is confirmed by FEM simulation that the proposed accelerometer is effective for obtaining high sensitivity.

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Disposable, built-in micropumps are key devices for biochip technology. In this study, we propose two types of all-polymer built-in micropumps driven by light. First one is a lobed micropump that generates flow by using positive displacement. The lobed microrotors are driven by a synchronized laser-scanning method. Second one is a single-disk viscous micropump that generates flow by using drag force surrounding the rotor. This pump generates flow just by rotating a single disk rotor in a U-shaped microchannel. These micropumps enable ultralow flow control on the order of pL/min. The ultralow flow rate will be useful for further integration and miniaturization of micro-total-analysis systems.

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This study deals with road recognition technology on vehicle using CCD camera. The image processing to need for the visible light such as human sight. The first of all, we check driver's ability of recoginition for road surface, and also the information and use at the disition process. As the result, luminance value is effective to decide the road condition. Luminance value of road surface, the albedo value, road temperature and equivalent friction coefficient at the lock braking are measured at running condition. Using the analytical results, we proposed the new index for road condition using ratio between luminance value and solar radiation. Using the index, it is found that the index is able to discriminate the forward road conditions.

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This study examines a lane tracking control system for motorcycles based on Steer-By-Wire concept to develop a lane keeping assistance system. We apply the optimal control theory based on a model-based control to the controller to follow a desired lane. By examining computer simulation using a simplified vehicle model, a good lane tracking performance is realized by evaluating the lateral displacement of gravity in the cost function of the optimal control. The tracking performance is improved by increasing the weight for the lateral displacement of the center of gravity.

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This paper deals with the construction of a rider robot for motorcycle. The robot which controls a vertical stability and a direction control of the motorcycle is constructed as a tool for evaluation of two-wheeled vehicle behavior. The control algorithm of the system is constructed based on control action of the human rider. For the lateral control, the system identifies using electric compass. Sub-handle system which simulates the rider arms is adopted with damper and spring, and it is controlled by servo-motor. As a result, it is shown that the rider robot follows the lateral displacement calculated using the directional angle and vehicle speed.

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In this paper, an experimental system to study the control of the slipping car is proposed. The system consists of a small model car and an on-board sensor system. The measurement system consists of rotary encoders on the wheels, a 2-axis acceleration sensor and yaw rate gyro. The measured trajectories and the estimation results of the car's mass are shown in this paper.

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OBD- II system, which takes out ECU data of the engine, has been equipped normally by the passenger car now. Moreover, GPS data as the driving position, the altitude, etc. are measured. Understanding the state of driving and the engine performance of the car from those measuring data becomes possible. The performance is classified according to the change of the car velocity, the slope of the road and the driving in a tunnel & out of a tunnel. In this time, we will report the analysis result of the brake powers and of the brake torques. As the result, a clear difference is confirmed by the classification when examining it in detail though they seem to be little difference. Especially, it is confirmed that the engine powers at driving in a tunnel on the return road are smaller than at driving out of a tunnel.

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This paper is proposed that the concept of the sharing in the steering operation both assistance system and the driver, and assisting the yaw angle as a driver assistance system that cooperates with the driver. Active rear steering control, which the driver steers the front wheel and the rear steer assists the yaw angle, takes the effect of cooperation and the lane-keeping in precedence research. In order to raise lane keeping performance, the steering reaction torque is designed using the vehicle dynamics of lateral direction for the driver's maneuver, and to reduce the driver's workload. It can be notice that this steering reaction torque has effectiveness of lane-keeping performance and of driver's workload.

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This paper presents a new rollover prevention control method of heavy-duty trucks or tractor-trailer combination vehicle using gyroscopic function of onboard flywheel device, primary function of which is energy storage system. Flywheel is becoming a strong option of energy storage device in hybrid system because of its high energy density and high power density; however, the influence of flywheel on the dynamic behavior of vehicle need further study. This paper proposed the use of gyroscopic function of flywheel to absorb roll moment caused by centrifugal force when sharp cornering to prevent rollover. Control strategy was considered and control performance was verified by numerical simulation.

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Isolation performance of an active suspension is examined by experiments using a large-scale shaking table. The nine subjects are exposed to vibrations, which are corresponding to car body vibration of active and passive suspensions. Ride qualities of the active and the passive suspension are evaluated by the results of questionnaires and sphygmographs of the subjects. The results of questionnaires indicate the ride quality of the active suspension is significantly better than the passive, while sphygmographs show no significant difference.

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This paper presents a new tilting control method of railway vehicle using gyroscopic moment obtained by onboard flywheel device, primary function of which is energy storage system. Flywheel is becoming a strong option of energy storage device in hybrid energy railway vehicle because of its high energy density and high power density. However, the influence of flywheel on the dynamic behavior of vehicle need further study. This paper proposed the use of gyroscopic moment obtained by actively controlled single-gimbal-mounted flywheel to tilt car body of railway vehicle when high speed curve passing in order to reduce sensory lateral acceleration of passenger. Control algorithm was developed and the performance was verified by numerical simulation.

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To increase the commercial speed of train, high-performance pantographs have been developed. Simultaneously, measurement methods of contact force between overhead contact wire and pantograph have been also developed for these pantographs. This paper introduces a new contact-force measurement method which applies relative acceleration between contact strip and panhead in order to measure inertia force of pantograph.

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