Surface of a polishing pad is shaved by using a rotating dresser in order to remove silicon scraps from the polishing pad. The dresser is held in a polishing apparatus touching with the rotating pad. In the first place, the motion of the dresser and the pad in the polishing apparatus was modeled mathematically in order to analyze the removal thickness of the pad. Distribution of removal thickness of the pad with an ordinary circular dresser was analyzed by using the mathematic model. The surface of the pad should be flat for flatness of silicon wafers. In the second place, a new oval-shaped dresser was proposed through the consideration of the circular dresser analysis. Finally a dresser shape optimization method was proposed in order to improve flatness of the pad. The Quasi-Newton method was used for the shape optimization. A penalty function was also used to take minimum removal thickness into consideration as constraints in the optimization. The optimized oval-shaped dresser gave better pad flatness and longer pad life.

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This paper describes a CAM system of drilling for Printed Wiring Boards (PWBs). We focused on drilled hole wall quality in addition to machining efficiency. The drill and PWB temperature in drilling was monitored using thermography, because the temperature had a relation to surface roughness of drilled hole wall. The various tool paths were evaluated in order to improve drilling efficiency with sufficient hole quality. As a results, we could have a suggestion of tool path for good quality of drilled hole wall.

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An Ionic Polymer-Metal Composite (IPMC) consists of a thin ionomeric membrane with noble metal electrodes formed on both surfaces. IPMCs have a potential as soft robotic actuators and artificial muscles with several advantages such as flexibility, light weight, and low driving voltages. Highly durable IPMCs will be fabricated using an electroless chemical plating technique to form metal electrodes. In this study, a fabrication method for patterning electrodes with a size of several micrometers has been developed to realize IPMCs, which will be capable of a peristaltic movement. A selective electroless gold plating and an epoxy-resin based photoresist are applied for patterning electrodes. By using a photomask with a pattern-size of 50 μm, patterned electrodes are formed on an ionomer (Nafion) membrane, resulting in the size of 65 μm. This pattern size is much smaller than that in conventional patterning methods using a selective electroless plating technique and masking tapes or stencil masks. The sheet resistance of the fabricated electrodes is lower than 30 Ω/□, which is almost same order of magnitude as that of electrodes formed by the conventional electroless plating without photolithography.

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Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The advantages of the SAW linear motor is thin structure, high force, high speed and precise positioning. On the other hand, the motor has a problem with wear of contact surface. The SAW linear motor consist of a LiNbO3 as a stator transducer and a silicon substrate with distributed projections as a slider. However, the stator transducer material is easy to wear out due to friction drive. Moreover the silicon projections enhanced wearing. Lifetime of the motor is reduced by the wear of the stator. To solve this problem, the silicon substrate with segment structured diamond-like carbon (S-DLC) films is applied as the slider instead of the silicon slider with projections. The films are expected to increase abrasion-resistant performance of contact surface and acquire the same driving characteristics as the conventional silicon slider. This report presents installation of the films on the slider surface and successful work of the motor. Observation of its performance is also indicated to be compared with the conventional one. The films deposition on a stator transducer is introduced. Successful driving of the motor with the stator transducer is also described.

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In the existing circumstances, a lot of oil is used in the cutting process and almost all oil is finally incinerated. One of the problem is that dioxin may be produced when the oil is incinerated. Therefore, we have to make a new cutting process to reduce these oils. A ideal solution to this problem is dry cutting, but the tool life is probably shortened because of the lack of cooling factor. Without the cooling factor, tool temperature increases significantly. About this heat process, we can surmise that, there are two factors in it. One of the factors is frictional heat between tools and work, and the other factor is generation of heat by oxidation. Then, the cutting in nitrogen gas can control the generation of heat by oxidation and increase the tool life. However in nitrogen cutting, higher, the concentration of nitrogen, more, the adhesion occurs. In this study, we tried to solve the adhesive problems by changing the cutting condition and tool materials. As a result, we can increase tool life such that high speed dry cutting is possible, which has been infeasible. Furthermore, Nitrogen cutting has the possibility that oxygen concentration changes the cutting characteristics by the lubricating effect of metal oxide film. In this study, we also turned our attention to that and examine the concern with nitrogen concentration.

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The grindability of fine-ceramics is the most important information in order to determine the optimum grinding conditions and dressing intervals. This study proposed the method of grindability evaluation of fine-ceramics by using removal rate in constant pressure grinding. The grindability evaluation is based on the change of removal rate accompanied by the increase in stock removal. As a result, the grindability could be evaluated quantitatively by using the change ratio of the removal rate on the basis of primary removal rate.

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In recent years inkjet technology has a wide range of application including Flat Panel Display and Semiconductors. As compared with consumer appliances, industrial inkjet requires higher specifications in terms of dot placement accuracy and droplet volume uniformity. The stability of inkjet is a major requirement and then an in-situ monitoring system for inkjet condition is strongly required to prevent inferior products. In piezo-driven inkjet heads, the piezo actuators can be used as sensors to detect jetting failures caused by air bubbles. This might be the key technology to improve the reliability of the inkjet process. In this paper, we propose the model of jetting failure detection system and point out how the modification of the inkjet driving circuit for better jetting performance influences on the detection results. The prototype of the jetting failure detection system is developed and used to validate the detection algorithm both in time and frequency domain. This prototype and detection algorithm can realize the in-situ monitoring for all jetting due to high-speed system configuration.

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In the present study, a novel integrated MEMS hematology chip that consists of complete blood count (CBC) sensor, hemoglobin (HGB) sensor and volume measurement sensor, was developed. CBC sensing is based on an impedance method that uses a micro aperture. On the other hand, the HGB concentration and sample volume were measured from optical absorption and optical refraction, respectively. Therefore, the integrated MEMS hematology chip was designed as a laminated structure; i.e. impedance layer (thickness 100 μm) including CBC sensor and optical layer (thickness 250 μm) including HGB sensor and volume measurement sensor. The integrated MEMS hematology chip was fabricated using a SU-8 photolithography process with build-in Cr mask layer. In addition, the proposed hematology chip was evaluated using an experimental device that simulates a POCT hematology analyzer. A trial measurement of control blood was successfully performed. The new MEMS hematology chip demonstrated potential application as a miniature hematology analyzer.

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To effectively use scanned meshes obtained by 3D laser scanner or X-ray CT scanning systems in engineering applications, such as inspection and CAD model reconstruction, we need to segment meshes and extract desirable regions and their approximating surfaces. Surfaces of engineering objects are commonly represented by a set of analytic surfaces, such as planes, cylinders, spheres, cones. Therefore, the mesh surface of them needs to be approximated by a set of analytic surfaces. In this paper we propose an efficient mesh segmentation algorithm based on region growing and region merging. Our algorithm first robustly and accurately estimates mesh principal curvatures using the two-pass estimation method. Then it fast extracts regions and their approximating analytic surfaces based on region growing even if regions are smoothly blended. Finally it efficiently merges initial set of regions of large and complex scanned meshes under the user specified tolerances using region merging. We demonstrate the efficiency and accuracy of our algorithm with scanned meshes acquired from real engineering objects by X-ray CT scanning systems.

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The most popular control method of bipedal walking robots is ZMP(Zero Moment Point) based control method. In this method, the torso is accelerated and decelerated by the motors in every step. It is not energetically efficient because natural dynamics is not used. Natural dynamics is to generate motion using mechanical features of the machine, i.e., as much as possible, without using the motors. A well-designed biped robot has its own natural dynamics suitable for efficient walking. Such natural dynamics is not considered in ZMP based control method. In this paper, we report on a biped robot: 'Tetsuro' designed with consideration of natural dynamics, and indicate inverted pendulum based control method using an approximate model and delayed stepping reflex, which can generate the efficient treadmill walking.

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In order to solve the energy supply problem for ubiquitous equipments, a gyroscopic power generator is proposed which utilizes kinetic energy of human movement. In the generator, a rotor increases spinning velocity by the precession and friction caused by input vibration. In this paper, first, the structure and the power generation principle of the generator are explained. Next, an analytical method of the rotor movement is presented and validity of the analysis is verified by the experiment using a prototype generator. Finally, the amount of the maximum power generation is forecasted to show the potential ability of the generator.

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In the field of Electron Beam Lithography apparatus disliking leakage of magnetic flux and heating, it is intended that air actuators are used instead of electro-magnetic actuators. However, due to the pneumatic compressibility, the settling time becomes long. The more the positioning gain is set large, the more the positioning system becomes unstable. To overcome this unstable phenomenon, it is well-known that the closed loop is stabilized using the parallel feedforward compensator (PFC). In order to realize the higher speed positioning, in this paper, the pressure feedback is implemented in the closed loop in addition to the series compensator induced from the equivalent transformation of PFC. Moreover the first-order differential to manipulate the stiffness, the disturbance observer, and the second-order differential to manipulate the damping are added. Under this control scheme, the feedforward compensator functions effectively. Using a pneumatic experimental apparatus, remarkable positioning results can be shown.

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