Titanium alloy is well known that is very difficult to machining. In particular, it is easy to generate the breakage trouble by adhesion of cutting edge, chipping and chip-jamming under water-soluble tapping. Therefore, not only wear resistance but also adhesion resistance is needed for taps. In this study, tapping test was carried out under water-soluble cutting in order to investigate an effect of composite surface treatment in tapping of Ti-6Al-4V material with different surface treatment on taps that were treated on coating to cutting face for wear resistance and treated nitriding to flank face of thread for adhesion resistance.

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Recently, cutting of the Tungsten carbide (WC) materials by using a polycrystalline composite diamond (PCD) milling tool has been realized. In previous studies, we have investigated about the surface properties of cemented carbide for cold forging which has been processed using the PCD tool. From the results of experiments, compressive residual stress occurs on the machined surface of the cemented carbide by the PCD tool compared with the polished surface after EDM. In addition, the hardness of the WC surface is slightly increased in the case using PCD tool. In this study, effects of types of diamond tools or particle sizes of the raw materials of cemented carbide were studied.

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In order to support a worker in task training, it is important to evaluate the worker's operation appropriately. The operation should be evaluated not only by the quality of the operation itself but also by the result brought from it. Engineering simulation can be used for the estimation of the result. However, conventional methods cannot deal with the worker's operation directly. In order to solve such problem especially in a pouring operation of casting process, a casting flow simulation method that can use the worker's recorded ladle motion as input is proposed in this paper. Next, a method to evaluate the worker's operation by the result of the simulation is proposed.

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In manufacturing products that consist of 3d woven structures such as CMC(Ceramic Matrix Composites), the aimed form of the product is achieved by bending a flat textile. In bending process, shapes of the yarns that constitute the textile are changed by the whole textile′s deformation, and those changes are to be simulated and visualized for the better design of the product. This study proposes a method of the simulation and visualization, using the data acquired from whole deformation and the model of the textile pattern as the smallest unit (we call it pattern cell). We applied trilinear interpolation to calculate changes of the yarns′ nodes, sections′ up vectors and tangent vectors in each pattern cell. And we established a method to get whole textile′s deformed yarns by connecting the pattern cells deformed severally. This can be applied to both simulated results of whole textile and designed shapes, so therefore this would be useful as design support method.

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Nowadays, industrial X-ray CT scanners have become powerful non-destructive and non-invasive tools for various applications in research, production and quality insurance. Since the performance of industrial X-ray CT scanners is considerably improved, there is an increasing demand for achieving accurate surface reconstruction of measured objects for dimensional inspection of mechanical parts. In this paper, we propose a novel method that reuses X-ray projection images, or a sinogram, to estimate the shape of real objects by fitting silhouette-lines of CAD polygonal mesh of real objects to the sinogram. Since there is no need to make CT reconstruction, we expect to get rid of the influence of CT artifacts such as beam hardening, cone-beam artifacts, etc., and obtain more accurate measurement results.

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Gaussian convolution is a fundamental and important tool in CG, CAD, and image processing applications. In this research, we propose a novel, fast, and accurate approximation algorithm to convolve a Gaussian function with images. Our algorithm is based on splitting a pixel domain into representative regions where we can efficiently perform discrete convolutions. Our algorithm is applicable to non-uniform pixels with linear computational complexity. We examine our algorithm numerically in terms of speed, precision, and quality.

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Edge-aware filtering is a fundamental and important tool in CG, CAD, and image processing applications. In this research, we propose a novel and fast edge-aware image filter. Our filter is based on the domain splitting and domain transform techniques. First, we transform pixel coordinates according to their geodesic distance on the image manifold. Next, we split a pixel domain into representative regions where we can efficiently perform discrete L1 Gaussian convolutions. Our filter consists of linear computational complexity without ring-artifact (which could be generated by box-like kernels).

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We propose formulation and application of aesthetic B-spline curves and surfaces as a new paradigm of representation of styling design. In previous reports, we have introduced formulation of aesthetic curves by minimizing the deviation of the curvature graph from a line for the n-th power of the curvature radius, and applied it to generate space curves and surfaces from boundary conditions and to fit input data to a space curve. In this report, we apply the method to fit input data to a surface after discussing surface curvature, then derive formulation for compound curves and surfaces and show their experimental results.

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An important aspect which contributes to perception of a product to be of high quality is the consumer′s experience while holding and maneuvering it during its use. The way a product feels in customer′s hand is a very important consideration for a product design these days. Apt examples would be products like Mobile Phone, Camera, and Hair Dryer etc. There are many parameters and considerations which constitute the ultimate feeling of a product while handling it but mass of a product and its distribution could be one of the prime considerations. Unlike functional requirements, it is not possible to quantify the feeling of handling a product which can only be perceived by actually holding the manufactured part. This makes it difficult for the designer to optimize the product for its handling. The aim of the proposed work is to fabricate prototype of the designed product using 3D printing such that it has the same mass and mass distribution as that of the designed product.

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