Positioning devices which are composed with linear ball guideways and a linear motor are increased in recent precision positioning field. However, it is a difficult problem to achieve precision or ultra-precision positioning because rolling frictional force of the linear ball guideways is a disturbance force. Therefore, a frictional compensation is implemented by a controller. In this paper, one-axis positioning apparatus using a voice coil motor as an actuator is constructed. Moreover, several control methods are full-closed loop of measured displacement feed-back, feed-forward control of reference position and feed-forward control as like inverse transfer function using nonlinear frictional model proposed by authors. The equivalent spring constant of the nonlinear frictional model changes by the displacement. As implementing positioning tests, it is verified that the feed forward control using the nonlinear frictional model is effective for achieving the precision positioning.

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A small precision nanomachining and measurement system was developed with a targeted machining resolution on the order of scales ranging from submicrons to several nanometers. The system was comprised of two machining functions, scratch machining and milling, and one measurement function. The scratch machining function was based on a frictional force microscope mechanism with a closed-loop numerical control (NC) to control the depth of the cut. A stiff cantilever was used for the scratch-machining function to permit nanomachining of hard and brittle materials such as silicon. The milling function used an original miniature tool that had a very small diamond mounted on it that permitted micromachining. The measurement function incorporated into this system used the same mechanism as the scratch-machining function, and provided a degree of precision almost equal to that of atomic force microscopy. After constructing this system, we performed various machining tests with it to confirm that the integrated NC closed-loop control function performed correctly.

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A mechanical breaking process after laser scribing is indispensable to complete the separation of glass substrate since the crack depth induced by the laser scribing is limited. Laser irradiation along the laser scribed line is introduced in this paper as a crack extension method in depth direction after the laser scribing of a relatively thick glass in order to make the mechanical breaking easier. Since the separating load decreases by extending the scribed crack deeply, it contributes to the inhibition of glass particle generation. The target of this research is to clarify the mechanism of crack extension by the laser irradiation along laser scribed line. Two-dimensional thermal elasticity analysis was conducted by a finite element method based on the experimental results in order to theoretically estimate the laser irradiation condition which extends crack. The following results were obtained. Compressive stress is generated on the glass surface and tensile stress is generated inside the glass by the laser irradiation along the laser scribed line. The tensile stress concentrates at the crack tip induced by the laser scribing, and the crack penetrates into the depth direction. The condition of crack extension can be estimated from the maximum surface temperature and the maximum tensile stress of the crack tip in practical processing velocity (200 or more mm/s).

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The ultra-smoothness grinding method based on the new concept, which can finish to almost the same smoothness formed by polishing method, in the first research, is developed as the countermeasure answering the recently strong requirement about high efficiency production of high quality components. In the 2nd report, the surface roughness of various kinds of workpieces formed with the #140 diamond wheel by means of the method is ascertained to attain below 50nm(Rz). Furthermore the influence of wheel speed on the surface roughness is investigated. In the report following the 2nd report, the influence of normal feed to grinding direction on the surface roughness is investigated. Below the critical normal feed, the surface roughness becomes below about 60nm (Rz) in three dimensional measurement of 256μm square. Over the critical normal feed, the surface roughness begins to deteriorate steeply to a certain value. Beyond the value, the surface roughness tends to increase gradually with the increase of normal feed.

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There have been many researches on the contouring control for machine tool feed drive systems. To the best of authors' knowledge, its effectiveness has been shown only by comparative experiments with industrial non-contouring (independent axial) controllers that are previously set up, or non-contouring controllers along with the contour error compensator such as the cross-coupling controller. Because the control performance largely depends on controller gains, such comparison remains some ambiguities to show the effectiveness of contouring control. In other words, a similar control performance may be achieved if the non-contouring controller gains are appropriately assigned. This paper discusses the effectiveness of contouring controller in both analytical and experimental manners. A basic formulation of a coordinate transformation based contouring controller and its effectiveness are shown. Because there exists an inherent contour error in the coordinate transformation approach, a method to reduce the inherent contour error is presented to enhance the effectiveness of contouring controller. The contouring controller is concluded to be effective, in that it provides a comparative performance to the non-contouring controller with less control input variance. This property seems to be useful for not damaging machine tool systems, and for saving required control energy.

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Chemical-mechanical polishing (CMP) has been widely accepted for the planarization of multi-layer structures in semiconductor manufacturing. High performance CMP for the planarization of premetal and inter layer dielectrics is strongly required. Conventional CMP process using the stack-type pads shows good within-wafer uniformity. However this process produces degradation in planarity, especially between center and edge areas of logic devices. In this work, we described an approach to the optimized dielectric planarization method using the hard-pad-based CMP process and achieve improved wafer-scaled uniformity and within-die planarity, simultaneously. By optimizing both polishing conditions and the consumables of the polishers, the hard pad-based process showed an at least 1.6-time improvement in step height reduction compared to the stack-type pad process and a comparable within-wafer uniformity.

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This paper represents the influence of drilling conditions upon centripetal action with radial run-out in the micro drilling of printed circuit boards (PCBs). These were examined experimentally with micro drills of 0.1mm in diameter at a rotational speed of 3 x 10⁵/min. The drilling behavior around contact area on a work surface was observed by a high-speed video camera. The conclusions obtained are as follows: 1) The centripetal action varies with physical properties of work material. The centripetal action is deteriorative in harder work material. 2) The centripetal action depends on feed rate. It is more effective at a lower feed rate, but doesn't depend on the geometry of drill tips. 3) Drilled hole quality is dependent on bending stiffness of a micro drill. The hole quality deteriorates at a higher bending stiffness.

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The progress of information technology and the popularization of the personal computer brought the growth of computer-based testing (CBT), which utilizes computer to hold an exam and rate examinees. Most of the current CBT can be regarded as an extension of the paper-and-pencil exam, and aim to assess the knowledge or the achievement of the examinees. On the other hand, very few CBT systems address assessing examinees' skill in sports or manufacturing.
This paper discusses a method to evaluate examinees' physical skill from their motion data, taking golf putt swing as an example. The motion data is generally represented as a vector time series. The recurrent neural network is introduced to deal with such data. We verified the effectiveness of the proposed method by collecting actual examinees' motion data and assess them using the proposed method.

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We propose changing-OPD (optical path difference) measurement technique which can be built in a scanning white-light interference microscope. The technique uses a laser beam introduced around an optical axis of the interference microscope. The laser beam reflected by a reference mirror in an objective lens and the laser beam reflected by a specimen surface make interferograms at an observing plane. These interferograms are continuously captured by a high-speed CCD line camera during a vertical scanning. Changing light intensities at two pixels having different phase and different modulations are normalized as having unity amplitude, and then subtraction and sum of them are calculated. From the calculated values changing phase is calculated and then change of OPD is also calculated after every interferogram capturing. To check accuracy of the proposed technique we carried out an experiment using a precision vertical scanning stage. After a 96μm vertical scanning, total changed OPD at different portions on the specimen surface are calculated and estimated having less than 10 nm in difference.

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The measuring system for evaluating the accuracy of a deep hole is developed by using the autocollimation principle. The system consists of a measuring unit and an optical system for light reception. The measuring unit detects the displacement of a feeler on the basis of the autocollimation principle. The optical system for light reception receives the laser beam irradiated from the measuring unit. In this research, the measuring accuracy and repeatability error of the system are evaluated by measuring the roundness, cylindricity and straightness of 110-mm-diameter holes of a ring gage and machined hole. As a result, it is clarified that the accuracies of the roundness, straightness and cylindricity measured by the measuring system correspond well to those by the tester in terms of both shape and value and that the repeatability error of 10 measuring measurements of roundness of machined hole is ±0.4μm.

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Two new heuristic procedures for re-entrant flow shop scheduling problem are proposed to plan a feasible production schedule in industrial manufacturing factories. Each job is assigned to one of idle periods within a limited time on a cyclic Gantt chart. One heuristic procedure is for an assignment of a target job on the machine while an adequate the idle time is remained for undecided jobs. Another heuristic procedure is based on solutions for two classical optimization problems, or a job assignment problem and a knapsack problem. The starting time of the target job is optimally determined at each step in the scheduling. The results indicate that the proposed procedures give a good schedule in comparison with the optimal schedule derived theoretically. The Calculation times are also evaluated and verified a validity of the use in actual manufacturing factories.

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Not only the sense of sight, but the sense of hearing is important to construct the virtual space with more reality. In general, a cost to calculate the sound exceeds a cost to calculate the image greatly, so it is difficult to realize the interactive virtual reality with acoustics. In this paper, we propose a method of calculating the transition of acoustics corresponding to movement of the user by fixation of the position of a sound source in virtual space. In our method, it is possible to realize the interactive acoustics by decreasing the window size of FFT, and introducing the multi buffer system.

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This paper addresses Scanning Electron Microscope (SEM). Not only the mechanical vibration but also electro-magnetic field influences the quality of SEM image. The vibration of the electron beam path also causes SEM image noise. We investigated the eigen mode shapes of the magnetic shield experimentally, and found out the frequency of the image noise measured with “Spot-beam analysis” corresponded to those natural frequencies. With changing the acceleration voltage of the electron beam, it was shown that the vibration of the magnetic shield affected magnetically to the electron beam path. As countermeasures, the damping structures with and without binding part were applied. Both structures were effective, however the structure with binding part changed the eigen modes of the magnetic shield and the frequency properties of SEM image noise. Thus, the damping structure without binding part would be more desirable to reduce the magnetic shield vibration. The damping structure had been applied to SEM, and remarkable reductions of the image noise from 250 to 500Hz band in 1/3 octave band were shown. This effect would be more remarkable when the acceleration voltage of the electron beam was smaller to reduce the electron damage to the specimen.

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