This paper reports a high-density coil winding technology that enables to fabricate high efficient and small motors. When a square wire is wound in contact, the density of the coil in the stator core slots can be higher than that when a round wire is wound like piling straw bags. However when the square wire is wound only by the motions of the nozzle and the rotation axis, the alignment of the wire is crumbled due to the gap caused by the slip of the wire. Thus a system that can wind square wire without gaps and crumbling was proposed. The system has guides that restrict the positions of the wire rotating with the coil. An experimental device of this system was driven at 2.5 rotations per second, and the guides were controlled in synchronization with the rotation axis. As a result, concentrated wound plural layer coils were fabricated without gaps by winding square wires in contact. The slot-fill rate of the experimental coil of a square wire is 80%, while the slot-fill rate of the conventional coil of a round wire is 68%. This system can be applied to the motors whose stators are constructed of divided cores, and it makes these motors small and highly efficient.

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In this paper, we describe the “Versatile Micro Robot” with newly developed suspension mechanism composed of parallel leaf springs for smooth contact of 4 legs on the surface. In order to provide microscopic operation, the unique locomotion mechanism which is composed of four piezoelectric actuators and two electromagnets is proposed. Here two legs arranged on cross each other are connected by four piezoelectric actuators so that it can move in any directions, i.e. in X and Y directions as well as rotate at the specified point precisely with the manner of an inchworm. To obtain 4 legs' smooth contact on the metal floor simultaneously, the robot is equipped with joint mechanism composed of V-shaped groove and cylinder-shaped magnetic core. However, the frictional and lubricated conditions are easily changed, so it has much of nonuniformity of translational motions in 8 directions. Parallel leaf spring mechanisms are often used as precision linear motion mechanisms because they are simple and free from friction. To improve the motion uniformity, we have developed suspension mechanism with parallel leaf springs. In several experiments, we have improved the uniformity of translational motions in 8 directions and decreased posture error. The possibility of this tiny robot for flexible positioning device is also discussed to open the new field for micro-robotics in precision region.

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Even if the ball screw is preloaded with a double nut in order to eliminate backlash between the screw shaft and the nut, linear actuators driven by ball screw mechanisms generate non-linear relationships between the linear motion of the nut and the rotary motion of the screw shaft when the ball screw drive is reversed. The behavior of the ball screw mechanism, which is referred to as lost motion, can contribute to positioning errors of linear actuators.
The present paper describes a method by which to calculate the axial stiffness of a ball screw with ball wedging and to determine the lost motion when the ball screw drive is reversed. An attempt is made to evaluate the ball wedging and the lost motion in a preloaded ball screw with a double nut by a comparative study of analytical and experimental results. The lost motion is determined to be produced primarily by the ball wedging. In addition, the effects of internal geometry in the ball screw on the lost motion generated by the ball wedging are analytical investigated based of the calculated results.

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This paper evaluates the response reproductivity of rolling friction models for precise positioning devices with linear ball guideways. The rolling friction in mechanism behaves different ways between macro and micro displacement regions, and deteriorates the positioning performance. In order to provide the precise positioning performance, the high precision numerical simulator is indispensable to analyze the rolling friction behavior and to design effective compensators. In this research, therefore, three rolling friction models : Koizumi model, Bristle model, and Rheology model, are comparatively evaluated to achieve the precise simulator. The reproductivity of the rolling friction models has been verified through comparative studies in numerical simulations and experiments using a prototype of linear motor-driven table systems with linear ball guideway.

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Many techniques have been developed to measure odor substances. However most of these methods are based on using aqueous solutions. Many odor substances, specifically at low density situation are difficult to dissolve into water. Finding the way how to absorb odor substances to get the highest concentration solutions within a limited time are key problems for olfactory systems. The Mist-Cyclone system has been developed to obtain a high concentration solution by blowing odor substances contained air mixture through the mist of water which has a huge contact surface generated by the ultrasonic transducer, and then separating the liquid from two-phase fluid by a cyclone unit. Eugenol and 2, 4-DNT were used as the odor substance in our experiments. Water solution samples were captured from 50 litters of Eugenol/air mixture gas at 0.13 ppm or DNT/air mixture gas at 0.06 ppm, and analyzed with GC-FID. As a result, Eugenol or DNT was detected respectively from the sample. By using with more sensitive method, it would be possible to detect or distinguish odor substance with much less amount of solutions.

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Recently, haptic information is studied as the third multimedia information. In order to control haptic information, bilateral control with a master-slave system is used widely. Since the plural systems are handled, it becomes important to think of the connection condition among the systems. In this paper, the multilateral control which changes the system connection depending on movement of the operator is proposed. The system connection is able to be changed without a switch by this proposed control. By using this proposed system, an operator can feel the environmental reaction force in the distant place. Moreover the operator can feel binding force from the system by changing the system connection when the slave system goes to the dangerous space. The effectiveness of this proposal is shown by an experiment.

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The fabrication process of Arrayed Waveguide Grating (AWG) for the Coarse Wavelength Division Multiplexing (CWDM) by the casting method using the micro die is proposed, and the optical characteristics are evaluated for the fabricated device. In the 1^st report, the fabrication process of AWG by the casting method was proposed. To fabricate the micro die, the electro-plating method after fabricating the mother shape using SU-8 was used. In this paper, the improved process of filling the core material to the core channel of the formed under clad using the spin-coater is examined. The condition of filling the core material is decided by optimizing the condition of the spin coating. The AWG is realized by the proposed method, and then the optical characteristics are evaluated. As the result, the wavelength demultiplexing are successfully confirmed.

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An overlay error was analyzed by the least square circle method and error factors were revealed in 3D microfabrication technology using surface-activated bonding. Ten-layered thin-film stacking structures were fabricated with several batches and the overlay errors determined by the shifts of the center coordinates of the layers were examined. It was found that the overlay errors were classified into three factors : (1) intra-cell random error of σ1 = 34 nm; (2) inter-cell random error of σ2 = 98 nm; and (3) inter-cell systematic error of 32 nm/mm. The dominant causes of the intra-cell random error were the patterning error of the thin films on a donor substrate 32.6 nm, and the measurement error 9.5 nm. The major causes of the inter-cell random error were the positioning error of XY stage 73.6 nm and the fluctuation of Z stage in XY directions 46 nm, each induced by the vibration of vacuum pump. The inter-cell systematic error was observed in spite of an alignment operation between the donor substrate and XY stage. An alignment simulation was revealed that the systematic error was developed by the random error of alignment mark coordinates acquired in the alignment operation. It was also demonstrated that the inter-cell systematic error was reduced down to 9 nm/mm by applying an average reading method of the alignment mark coordinates.

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This paper deals with the influence of various cemented carbide hob materials coated with TiN and (Ti,Al)N films, which are no coating on the rake face by grinding, on flank wear (tool life), crater wear and finished surface roughness in hobbing with minimal quantity lubrication (MQL) system compared with dry cutting. Experiments were carried out by simulating hobbing by fly tool cutting on a milling machine. As a consequence, the following results were obtained. (1) The tool failures do not occur with the TiN-coated P20 and P30 hob materials both in dry cutting and with MQL system, which showed the stable cutting. The flank wear obtained with the P30 is smaller than that with the P20, and the P30 also showed a good performance in the case ofthe coated (Ti,Al)N film. The MQL system showed the flank wear reduction effect compared with dry cutting. (2) The crater wear reduction effect by MQL system was recognized, and moreover the MQL system decreases the occurrence of the thermal cracks on the rake face. (3) The MQL system improves the surface roughness, even if the kinds of cemented carbide hob materials and the coating films were changed. (4) From the viewpoints of the flank wear, the crater wear and the finished surface roughness, the MQL system is effective for the cutting tool of (Ti,Al)N-coated P30, as a hob material.

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This study deals with a new planning method of minimum shank length for multi axis control machining. In conventional method, it is designed to deal 3+2 axis control machining and it assumes that tool posture is fixed in machining process. In this paper, we focus on continuous control machining and propose a new planning method based on parallel processing with general purpose graphics processing unit (GPGPU). In the proposed method, required shank length to avoid collision between polygon as approximated shape of workpiece and tool holder is calculated in each polygons individually. Then, the minimum shank length for each tool posture is estimated by comparison among the required length for each polygons. In this paper, we mention about the algorithm of the proposed method and explain the developed prototype estimation system. The developed system can detect the minimum shank length for each tool posture on continuous multi-axis control machining within a few hundred milliseconds.

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