In a production process of railway vehicles, several panels such as a ceiling panel and side panels are assembled by fusion welding. The welding heat causes the assembled vehicles to be slightly distorted. In the next interior fitting process of the railway vehicle production stage, a huge number of component parts must be fitted, such as air conditioning units and frame bars for straps, etc. It is very difficult for those parts to be fixed into the railway vehicles since the bolt holes are not in right positions because of the welding heat. Thus, it is of very importance to measure shapes of the panels and the bolt holes after the welding process. In a previous study, we had developed a new type of laser coordinate measuring machine with a laser distance meter and two galvano mirrors. The laser coordinate measuring machine can't cover the railway vehicle at a time. The railway vehicles have to be measured for the laser coordinate measuring machine to be moved three times and the measured data have to be connected by stitching technique. In this study we have developed two kinds of data stitching techniques and examined which method is suitable for the railway vehicles through the experiments.

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In the field of roundness-error measurement, a lot of methods applying the software datum are well known, such as the reversal method, the 3-point method, and the multi-step method, etc. However, some of these methods are not practically used at factory site due to complicate data acquisition and expensive sensor system. In this paper, the merits and demerits of various software datums were examined. Based on the results, a new method convenient for factory site was proposed combining the specimen sifting method using single displacement sensor with the data interpolation method by superimposing of phase sifted discrete profile data. Sufficient data density equivalent to the reversal method and multi-step method is obtained by the method proposed. The radial profile measured by the method is coincided with that by a commercial roundness measuring machine.

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The relationship between the phases of a multi-phase steel and the machined surface defect characteristics & the chip separation mechanism is reported. Steels industrially supplied for machining applications are classified into three categories according to the phase. Five grades of steel representative of each were machined orthogonally with a carbide tool, JIS K10. The main conclusions are as follows. When the steel consists of precipitate carbides and a single phase matrix, the machined surface defects are micro-cutting tracks made by the WC particles of the tool and fine defects by fracture near the boundary between the precipitate carbides and the matrix of the steel. The surface roughness (Rz) is small, in the range of 2 or 3 μm. The chip is separated by micro-cutting. When the steel consists of multiple phases which are easily plastically deformable, the machined surface defects are large defects caused by fracture near the boundary between the phases. The surface roughness (Rz) is large, scores of μm. The chip separation is the result of fracture between the multiple phases. It was confirmed by review of previous documentation that the relationships described above should be widely applicable to multi-phase steels.

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The purpose of this study is to develop plastic moldings with distinguishing tactile characters for various industrial applications. Pillar textures with the size of several hundreds of micrometers were fabricated on plastic molding surfaces, and the effect of texture shape on the human tactile sense was investigated by self-reported data collection and multivariate statistical analysis. The sensory evaluation revealed that the recognition of tactile senses depends on the physical properties of the texture. This tendency was different from that of the grooved texture with the size of several tens of micrometers. The tactual sense was also compared with leathers and closes. The tendency of the pillar textures was correlated with that of leathers and closes. The micro-groove-textures had distinguishing characteristics compared with these larger textures.

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NC machine tools generate desired shapes by control relative motions between tool and workpiece. Since several motion paths exist to machine the products with NC machine tools, it is difficult to choose the suitable motion path for the machining. This study focuses onto the energy consumption of feed drive systems of NC machine tools during the machining motion. In this study, an evaluation method by prediction of the energy consumption for each tool path is proposed. The evaluation method can predict the energy consumption of the feed drive systems during the motions. In order to confirm the correctness of the proposed method, actual measurement tests of the energy consumption are carried out. As the results, it is confirmed that the proposed method can evaluate the motion path based on the energy consumption.

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