This paper proposes a mathematical model of CNC rotary table driven by worm and spur gears. Proposed mathematical model has 4 degrees of freedom; rotational angle of motor, rotational angle of worm shaft, axial displacement of worm shaft, and rotational angle of table. Backlashes of spur and worm gear are also introduced into the model. Mass and inertias are calculated from designed drawings, and Coulomb's and viscous frictions are identified by matching motor torque curves under sine wave motions. Frequency response of the driving mechanism is also measured to identify axial and rotational stiffness. In order to confirm the effectiveness of proposed model, an experimental set-up consists of the rotary table and personal computer with a DSP board is modeled. Step response, rotational fluctuation, and influence of unbalanced mass are measured and simulated. As the results, it is confirmed that the proposed model can well simulate actual behaviors.

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This study presents a two-dimensional monitoring system for precise process control of end milling processes that involve the use of small-diameter tools. This system enables the measurement of tool deflections and cutting forces in two directions : the cutting or tangential direction and the feed or normal direction. Furthermore, this monitoring system makes it possible to estimate periodic changes in tool deflection during a given turn. In this study, this system was applied to side-milling using a small-diameter end-mill. The experiment was performed by end milling a steel plate at different depths of cuts and different radial depth of cuts, and feed rates. Tool behavior in side- milling was examined by this system, and it was compared with the tool behavior examined in slotting. In addition, the relation between the machined form of workpiece and the examined tool behavior was considered. The results of the in-process measurement of tool deflection in side- milling suggest that periodic changes in tool deflection during a given turn are related to the rotation angle of the tool and the number of tool edges. Furthermore, prediction of the machined form of workpiece was found to be possible by estimating tool deflection.

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A surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The advantages of the SAW linear motor are thin structure, large output force, high speed, precise positioning and so on. On the other hand, the motor has a problem with wear of contact surface. The SAW linear motor consists of a LiNO₃ substrate as a stator transducer and a silicon substrate with distributed projections as a slider. The stator transducer material, however, is easily worn due to friction drive. Moreover the silicon projections may enhance the wearing. Lifetime of the motor is reduced by the wear of the stator. To solve this problem, previously, segment-structured diamond-like carbon (S-DLC) films have been applied to the stator transducer surface. Enough driving performance has not been observed yet by the stator with the S-DLC films. The reason of this problem was edge shape of segments of the S-DLC films. In this report, we propose a new preparation method to fabricate the S-DLC films with round edge. Trial fabrication of the structure, abrasion test for the driving surface and driving characteristic with the stator are also reported.

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On the basis of the fact that the main cause of the formation of a deformed layer remaining on a machined surface is the extension of the shear zone to below the intended depth of cut, the relationships between the plastic flow remaining on the machined surface and the cutting parameters are analyzed using a simplified cutting model including a plastic flow layer on the machined surface and confirmed experimentally by low-cutting-speed orthogonal cutting tests on 60-40 brass and aluminum. The shear stress of the plastic flow layer, which was unclear in the previous paper, is estimated. It has generally been recognized that the total cutting energy mainly consists of the shear energy at the shear zone in front of the tool edge and the energy consumed in the friction between the tool rake face and the chip. It is confirmed in the present study that the energy consumed in the formation of the plastic flow layer remaining on the machined surface cannot be neglected because the plastic flow energy may become equivalent to or larger than the friction energy on the tool rake face.

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Recently, in accordance with the technical development and miniaturization of the information equipments, the demand of optic elements with high precision and miniaturization is increased. The mold is used in the manufacture of the optic elements. Thus, it is needed to machine the mold with high efficiency and high precision. As the material of mold, hard material including cemented carbide and ceramics is used. However, it is a problem of the occurrence of severe tool wear when hard material is machined. To solve this problem, cutting point swivel machining by using the diamond tool with special chamfer was proposed, which has the ability to suppress tool wear and to realize ultraprecision machining. The effectiveness was verified by the microgrooving experiment of SiC. The study aims at investigating the effect of the cutting point swivel machining, and the cutting force and tool wear with different tool rotation speed. As a result, the effect of the cutting point swivel machining is made clear, and the relationship among tool rotation speed, cutting force and tool wear is known.

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Grinding fluid is generally supplied from the supplying nozzle to the grinding point. However, if the amount of the grinding fluid is decreased, it is difficult to reach the grinding wheel because the air layers which rotate with periphery of grinding wheel rotating in high speed. Therefore, the system which can supply the grinding cutting fluid through the grinding wheel was developed and evaluated. Grinding force and grinding surface temperature were measured by applying the developed supplying system with varying the amount of the coolant supply. As a result, it was clarified that smaller amount of the coolant supply can keep the cooling and lubricating effect comparing with the conventional coolant supply.

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This paper proposes a novel method on speech simulation for Japanese with some anatomical basis, which can cope with any individual faces without any expensive measuring machines. We model the muscle models around the mouth, especially the orbicularis oris model and the ones supporting it, which play important roles to decide the movement of the skin around the mouth when we speak. They are represented as wire-frame models and their vertices play an important role when we treat them as the operation points of the GFFD (Generalized Free Form Deformation) method. Based on the model, we present a new method to represent the fusion of the skin motions caused by both speech and facial expression. Finally, we will show the visual effects of our method.

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Recently, changes of plant equipments become more frequent, and the construction of as-built models of the existing plant from laser scan data is expected to make the reconstruction processes more efficient. The purpose of this research is to propose an algorithm which can recognize a piping system from terrestrial laser scan data of plant equipments. The straight portion of pipes, connecting relationship of the piping system can be recognized in this algorithm. Eigenvalue analyses of the point clouds and of the normal vectors enable the recognition. Using only point clouds, the recognition algorithm can be applied to registered point clouds and can be performed in a fully automatic way. The recognition results of real plants have shown the effectiveness of the algorithm.

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