Laser shrink fitting for shaft coupling was developed as application of laser forming. The coupling of the bar and pipe of stainless steel is made by laser shrink fitting. A bar is inserted into a pipe, and the pipe surface of the bar-inserted-part is irradiated and heated by 1kW class laser. Metallographic structure of the laser irradiated part of the pipe is not changed. The fitted part of the pipe is shrunk in both circumferential and axial direction. The residual stress on the surface of the fitted pipe is a tensile one in the circumferential direction. No residual stress exists in axial direction. The tensile strength of the fitted part is nearly equal to the tensile strength of base metal of stainless steel pipe.

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Potassium dihydrogen phosphate (KDP) is a non-linear optical and water-soluble crystal. However, the KDP is brittle material. Therefore, it takes a large cost to obtain the surface roughness required in generating harmonics. A new polishing method using YAG laser beam is developed and verified the method by experiments in this paper. A YAG laser beam is focused at the edge of the end face of a single crystal in a saturated solution. The laser beam is scanned along the edge of the end surface. It is possible to polish the scanned surface and the other portions are not removed in a saturated solution. In this paper, the influences on the surface roughness of a KDP crystal are examined from the conditions related to the dose of the laser beam power, scanning speed and repetition of scanning. The surface roughness of a KDP single crystal could be improved by this method in the wide conditions of the beam scanning.

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Thin plates of lead magnesium niobate-lead titanate (PMN-PT) single crystal were ground with various cup-type resinoid-bonded diamond wheels on an ultra-precision surface grinder to obtain super smooth surfaces. The ground surfaces and sub-surfaces were observed with various instruments, such as laser microscope and atomic force microscope. The grinding modes such as ductile, ductile & fracture, and fracture modes are affected by grinding conditions. The relationship between finished surface roughness and grinding conditions was clarified experimentally. Very smooth surface less than 1nm Ra without micro-crack was obtained by ultra-precision one pass grinding. Compared with polishing, very sharp edges were also obtained by ultra-precision grinding.

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Laser processing using axisymmetrically polarized beams, such as radially and azimuthally polarized beams, was simulated to investigate influence of beam polarization from a point of view of behavior of light. A numerical simulator based on a ray-tracing method was developed to calculate drilling holes and digging grooves including influence of multiple beam reflection of polarized light. Simulation results showed that, even in digging grooves, the absorbed energy of reflected light was greater than that of incident light at the first reflection, especially in the case of the circularly polarized beam. Reflected rays of light of the radially and circularly polarized beams contributed to making grooves deep. Reflected rays of the azimuthally polarized beam contributed to broadening the groove.

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A group decision making process is often adopted for creating, comparing and prioritizing multiple alternative solutions to a problem. This paper proposes a semi-structured discussion approach involving Delphi type interaction for properly managing such a group decision making process. The approach divides a whole discussion process into several rounds, and, at the beginning of each round, the members' overall evaluation scores on the solutions at the time are aggregated and their distribution is visually feedback to each member. This makes it apparent how differently minorities evaluate the solutions. As a result, the focus of discussion is spontaneously drawn to, for example, background information of the difference. This can prevent the group from falling into groupthink and lead to a higher quality decision integrating the intellectual contributions of not only majorities but also minorities. Further, laboratory experiments are conducted to confirm whether the proposed discussion approach works as expected.

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Terrestrial laser scanners can capture dense point-clouds from engineering plants. Dense point-clouds are useful for collision detection of objects that move in engineering plants. We propose a real-time collision detection method for large-scale point-clouds. In our method, statuses are classified into collision, no collision, and unknown. The unknown status indicates that points are missing at the object position because of occlusion. Collisions are evaluated on depth-maps, which are generated from point-clouds. Two-resolution of depth-maps are used for improving performance. High-resolution depth maps are used only when objects collide on rough resolution depth maps. Our experimental results show that our method could quickly detect collisions between a large-scale point-cloud and mesh models.

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During design process in clothing production, states of wrinkles and folds formed on dress according to human posture and movements are an important design element. However envisaging the wrinkles and folds is not easy because fabric states strongly depend on mechanical properties of a fabric. In this paper, a fabric model taking into account slipping of the warp and the weft at the contact point of them is proposed and a fabric simulation system using this model is developed. In addition, the effectiveness of the simulation system based on the proposed model is confirmed by using a θ-φ function defined from the fabric state obtained in the fabric simulation.

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This paper presents an advanced technology for visual defect inspection. Line sensor is usually used to inspect defects on web-shape products such as long films. However, one-dimensional image data captured via line sensors always includes restrictive optical information about defects. Therefore, inspection performance is limited. With the advantage of using area sensors, two-dimensional images containing more optical information can be obtained. A novel imaging procedure named LCI(Line Composition and Integration) method is shown. The LCI extracts defect images from two-dimensional motion images in real-time. The experimental results show that the new image processing framework enhances the appearance of defects. An in-line web inspection system for film manufacturing lines is also presented.

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