In this paper, a system for measuring flow of pedestrians using a stereo camera is proposed. The system does not need adjustment after installation and its installation environment is not restricted. The proposed method consists of two stages, i.e., estimation process and measurement process. Estimation process automatically estimates parameters that are typically adjusted manually after installation by using images and distance information obtained from a stereo camera. Measurement process measures flow of pedestrians using one of the two methods, i.e., particle filter and a method using KLT and Voronoi. The selection is performed depending on the congestion level of the pedestrians. The proposed method is evaluated through experiments for four scenes that are typical in real operation.

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This paper discusses the method for the automatically generating stroboscopic image from a video image using a handheld camera comprehensively. The stroboscopic image can be used in order to measure stride length and speed of the runner based on the authors' previously proposed method, in which it is shown that measuring stride length and speed of the runner from the stroboscopic image is theoretically possible. The proposed automatic stroboscopic image generating method has two steps. The first step is generating a stitched background image from input video image. In the second step, runner images extracted from arbitrary frames are overlapped onto the stitched background image. Thus, this method can generate a stroboscopic image including the runners in arbitrary frames without overwriting them in some frames. These processes can be executed automatically, and these are noteworthy features. In the experiments under various environment to show the effectiveness of this method, it was confirmed that could generate a stroboscopic images well in respectively environment. It is also demonstrated that stride length and speed of the runner captured into the generated stroboscopic image can be measured with satisfactory accuracy by manually selected landing points in the stroboscopic image.

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There is a need for precise extrinsic parameters of vehicle mounted cameras in order to provide a good overhead view image to the driver. In this paper, we propose a simultaneous estimation of the extrinsic parameters of multiple fish-eye cameras using simple calibration targets. The proposed method estimates the parameters directly from the fish-eye images, giving more accurate results in comparison with a previous method that uses perspective projection converted images. Moreover, this method allows parameter estimation by simply arranging calibration targets anywhere around the vehicle. We conducted two experiments to quantitatively evaluate the estimation accuracy of the proposed method. In each experiment, two cases have been considered. In one case (the known case), targets' position were known beforehand. In the other case (the unknown case), targets' positions were unknown beforehand. In each experiment, the estimation error for the unknown case was 4-5 times bigger than the known case. In a simulation experiment, we compared the estimation accuracy of different target shapes, in order to identify the optimal shape of the target. The cubic shape turned out to be the most appropriate.

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Fast M-Estimation Gaussian Filter (FMGF) is the robust filter with the low computational cost of which transmission characteristics agrees with Gaussian filter's one if and only if without an outlier. 1D-FMGF is verified to possess all of the three major characteristics of filters for linear roughness measurement (“characteristic agree with Gaussian filter”, “high-speed” and “robustness”) is verified. In this paper, FMGF is applied to the areal surface texture. When 1D-FMGF is applied repeatedly in perpendicular directions, FMGF meets the requirement “directional characteristic”. However, if with an outlier, FMGF does not meet the requirement of “directional characteristic”. Then, this paper proposes new FMGF by changing some processes. New FMGF is confirmed that it could obtain “directional characteristic” if outlier exists, too. And finally it was confirmed that the FMGF could obtain all of the four major characteristics of filters for areal surface texture.

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This paper presents differential facing filter (DFF) in consideration of quantization for detecting foreign materials on an adhesive sheet. DFF is a binary filter for determining the target pixel is a foreign object or not. The determining method is based on gradient directions of two pixels. The two pixels consist of the target pixel and the facing pixel. Basically, if gradient directions of the two pixels are facing each other, DFF determines the two pixels are a foreign object. Otherwise, DFF determines the two pixels are other. However, DFF without consideration of quantization has a spatial quantization problem to select the facing pixel. Therefore, DFF in consideration of quantization select the facing pixels in horizontal direction and vertical direction. In experiments, we demonstrate that this method is capable of discriminating between foreign materials and others. We test our method on several data sets made by ourselves. The results show that our method achieves better performance compared to adaptive thresholding.

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Cutting experiments were conducted to investigate cutting characteristics of Niobium plate. Niobium is used for a super-conductivity material such as an acceleratator cavity because of its high conductivity, ductility and anti-corrosion property. However, mechanical engineers are unfamiliar with not only the material properties but also the mechanical properties. Hence, the cutting charactersitics have yet been determined. The cutting charactersitics such as cutting forces, machined surface properties, chip formation mechanism are not investigated sufficiently. The results indicated that the cutting provided not smooth chip formation: less than 30 degree rake angle tools offered unstable chip formation which means alternating change in the chip formation at the same depth of cut: unstable chip formation resulted in chipping of tool edge.

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This study aims to control chatter vibration of the large and thin flexible machining parts such as impellers by attaching dampers on the work piece in milling. These machining parts have so low stiffness that the chatter vibration is easily excited. Since the vibration decreases the productivity and machining accuracy,it is important to control the vibration by increasing the dynamic stiffness of the machining parts. In this research, a design method of the tuned mass damper (T.M.D) for suppressing the chattering by attaching same vibration characteristic dampers was proposed. The trial dampers which were optimized by using proposed method could decrease less than 57% of maximum amplitude of the impeller, and improved the roughness of the finished surface comparing with the case of without dampers.

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In charged particle optics, high-precision alignment of multistage multipole lens is essential for the realization of a non-rotationally symmetrical correction-lens system. A six-stage self-aligned quadrupole correction-lens system consisting of six quadrupoles and four aperture electrodes was designed and constructed. Machining accuracy and high-precision alignment techniques for the multistage correction-lens elements are reported in this article. The correction-lens system is assembled using cylindrical components, which can be machined with high accuracy. To overcome the problem of azimuthal error in the multistage quadrupole lens, the correction-lens system consists of two lens-casing cylinders of the same shape and size. To suppress azimuthal error among three quadrupoles in a lens-casing cylinder, four long positioning shafts and eight ceramic insulating shafts are inscribed in this cylinder. Cylindricity of the positioning shafts is less than 0.2μm over a length of 65 mm. Quadrupole electrodes are mounted on four pairs of ceramic insulating shafts using a Z-axis positioning jig. All sets of quadrupole electrodes are finished with varying diameters and lengths less than 0.15μm. The constructed multistage quadrupole correction lens is installed as an objective lens in a focused ion beam system, and azimuthal error between two lens-casing cylinders are corrected by using scanning ion microscope images.

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