In this paper, tennis matches are analyzed, and skills of players are evaluated quantitatively by computer vision technology. Two cameras are used to detect the 3-dimensional positions of balls and players. Subtractions of images are used to detect ball images and the prediction of ball positions by using velocity vectors of previous images enables accurate and high-speed ball detection. Players are accurately detected by elimination of white coat lines using image processing technologies. The sequential pictures of tennis experts and beginners were recorded and five scenes, which include tennis play skills, were analyzed quantitatively. The 3-dimensional trajectories of balls and players are calculated and skills between experts and beginners are compared, and the prominent differences between experts and beginners were recognized quantitatively about the trajectories of balls, movement and positions of players, height of balls and speeds of balls.

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This paper proposes an optimization of measurement strategy for geometric calibration of a CMM. In the calibration system, a vector of three-dimensional geometric deviations is modeled by twenty-one parametric errors on three-axes at first. Moreover a measurement strategy that solves the optimum solutions of the model is designed using two evaluation measures in second. This measurement strategy takes account of traceability of artifacts and uncertainty of measurements, so it enables to quantify the statistic reliability to the estimated parametric errors. In this study, we estimated parametric errors and calibrated the CMM in practice and made certain of the efficiency of the calibration system from ball plate measurement.

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A multilevel computer generated hologram (CGH) was fabricated for shaping a laser beam profile of a high-power CO₂ laser. The surface relief has eight height levels with 0.94μm in step heights. A copper surface relief was formed on a flat copper substrate by electroplating with photo-resist masks. Standard deviation of the surface step height was less than 22% of the designed height. The CGH changes a CO₂ laser beam of 14mm in diameter to a rectangular beam of 1mm×4mm and its diffraction efficiency was 69.2%. A 200W CO₂ laser beam of 14mm in diameter did not damage the CGH surface.

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We propose a method to improve the resolution of a linear encoder by optimizing the design of the photo detector cell pitch. High-performance optical encoders generally achieve high resolution by electrically dividing the sinewave-shaped output signal of the photo detector. In a linear encoder, resolution is determined by the amplitude from the photo detector. However, the slit pitch of the projection image on a photo detector is larger than photo detector cell since the influence of the oblique directional light from the LED, the amplitude of the output signal from the encoder's photo detector is decreased. This, in turn, decreases the resolution of the linear encoder. This paper describes an optimized design method using an optical system simulator of the linear encoder. To confirm this method, we evaluated the resolution of an actual linear encoder using the optimized photo detector. From this, we found a 30% improvement in the resolution of the linear encoder.

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In this report, the behavior of the cutting force measured through the dynamic response of tool-work piece system in ultrasonic vibration cutting was discussed first. Measured cutting force mainly depends on the ratio of net cutting time to vibration cycle in vibration cutting (t_c/T) because the tool-work piece system has much lower natural frequency comparing with the ultrasonic vibration cycle. It was confirmed by the newly proposed cutting experiment using resonated-hone-type work piece, displacement amplitude and stress amplitude at the cutting point vary continuously in this device. It was shown that the measured cutting force varies corresponding to the displacement amplitude. It was also indicated that the measured cutting force doesn't decrease when the cutting point is on the node of the resonated-hone-type work piece, where the stress amplitude is the maximum but there is no displacement amplitude. It means that there should be the relative intermittent displacement between the tool and the chip in order to decrease the measured cutting force. In addition, the deformation resistance of the work piece material itself doesn't decrease with ultrasonic vibration of the stress field. Secondly, the significance of the elastic deformation of the tool-work piece system of several microns in ultrasonic intermittent cutting was also indicated from analytical and experimental point of view. The effect of the elasitic behavior on the cutting force becomes relatively large as t_c/T becomes small.

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This paper proposes a micro multi-edged tool made of silicon as a new tool in the micro/nano-cutting and the decision system of fabricating conditions to the tool. This new tool is expected to machine a softer material, like aluminum alloy, glass and so on, than iron because silicon is as hard as alloy tool steel and high speed tool steel. On this new tool, the pyramidal etch hillocks on Si(100) surfaces etched in aqueous KOH solution function as cutting edges because the shape and distribution of the hillocks are resemble to those of the cutting edges on grinding wheel surfaces. The multi-edged tool can be fabricated at the desire of user by only adjusting the etching conditions suitably because the topography of hillocks depends on them. Therefore, we have developed the decision system of the etching conditions corresponding to a specified tool. In this system, the genetic algorithms and the neural network model are applied and the suitable etching conditions; - temperature, concentration and time - are output corresponding to the inputs of average height and number of the hillocks. In this paper, the system is proved fit for practical use as the result of experiments.

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As ULSI feature dimensions continue to shrink, wafer flatness of less than 0.1μm has become essential, and any flaws in surface topography cause serious problems in device patterning. CMP has become a standard technology to planarize surface topography. We have developed an oscillation-speed-control-type sequential grinding and polishing machine and have simulated the polishing process. A previous paper showed that experimental profiles polished with normal and reverse rotations agreed well with the simulated result calculated with a modified equation of relative velocity. However, the simulation broke down when the tool overhung the wafer by a significant amount. This paper presents measured pressure distributions for various tool overhangs, and a method to compensate for the difference between theoretical and experimental distributions, and polishing amounts produced using the compensation. The pressure distribution from air pressure in an air-bag is significantly different than that from a weight, and its characteristics depend on the machine. The profile of the pressure distribution for large overhangs becomes concave rather than linear. The simulated results with concave pressure distributions agreed well with experimental results.

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The research deals with the ultra-smoothness polishing technique of a glass type of magnetic disk substrate. The influence of polishing pressure on the removal rate and smoothness in polishing of a glass type of substrate with cerium oxide abrasives is experimentally examined and discussed. The substrate surface roughness is measured with a contact type of ordinary profilometer, interferometric surface profiler and AFM. The substrate smoothness is evaluated from the standpoint of the slight undulation Hw(Rz) and the surface roughness Hr(Rz), which are obtained by measuring 4mm and 250μm in the length of substrate surface, respectively. The substrate removal depth increases linearly with polishing time. The substrate removal rate becomes larger for higher polishing pressure. Over a critical polishing pressure, the removal rate is expressed by a simple equation related to polishing pressure. The slight undulation and surface roughness converge finally to a terminal value corresponding to a given polishing pressure, respectively. The terminal slight undulation increases somewhat with polishing pressure. The terminal surface roughness, on the other hand, is influenced little by polishing pressure.

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