Elevator manufacturers are responsible for securing the safety and maintaining the performance, cleanliness and cosmetic appearance of the elevators which they have sold. The purpose of this paper is to develop the cost-optimized after-service strategy for an elevator part. First, in order to find the optimum maintenance method, the replacement probability and the inspection probability of the part are derived theoretically under each of the three maintenance methods; Time Based Maintenance(TBM), Condition Based Maintenance(CBM), and Breakdown Maintenance(BM). Then, the approach to determine the cost-optimized maintenance is pre-sented and the relationship between the failure characteristic of the part and the cost-optimized maintenance is discussed. The result of using the proposed approach is compared with the one obtained by Online Quality Engineering (Taguchi Methods). Finally, from numerical experiments, it is shown that this approach can provide a more cost-effective and better maintenance method than the one given by Online Quality Engineering.

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This study has proposed a new coordinate measuring machine (CMM) based on a spatial parallel mechanism consisting of closed loop link mechanism. In conventional CMM employing of XYZ mechanism, the motion error of the mechanism strongly influences the measurement accuracy because of violation of the Abbe's principle which is the basis of the precision measurement. In this paper, the relationship between the link layout of proposed mechanism and the influence of joint runouts on the measurement error has been investigated analytically and experimentally. The obtained main results are as follows. (1) The joint runout in the scale direction strongly affects the measurement error. (2) Effects of the runouts except the scale direction are negligible when the measuring point is in the extensional direction of the scale. (3) The dispersion of measured value has decreased in above link layout. In conclusion, the Abbe's principle can be applied in proposed parallel mechanism.

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To understand the relation between arterial pressure (AP) waves and intracranial pressure (ICP) pulse waves, animal experiments using adult cats and computer simulation using linear vibration model are conducted. In animal experiments, hypercapnias are performed. Equivalent compliance and equivalent mass are estimated by computer simulation using AP and ICP wave data measured by animal, experiment. During the increase of ICP at the beginning of experiments, the equivalent compliance decreases to low value and equivalent mass increases to high value. And when ICP returns to the initial low levels, the equivalent compliance and equivalent mass recover to the initial value. However, after several experiments, although ICP returns to low level, the equivalent compliance remains low value but equivalent mass recovers to low one. These results suggest that the compliance estimated by the computer simulation is available for the indicator of pathological changes in intracranial functions. And the increase of the equivalent mass is caused by that the flow rate of cerebrospinal fluid, which flows through narrow crevices in cranium, increases due to the rise of ICP. This phenomenon is verified by a vibration analysis of experimented results based on a dynamic model.

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The flash temperature of a dental hard tissue irradiated with pulsed Nd:YAG laser is measured using a two-color pyrometer with an optical fiber. This pyrometer consists of a chalcogenide optical fiber and a laminated infrared detector. The influence of the laser power on the temperature of the dental tissue is investigated, and the relationship between the laser power and the removal volume of the dental tissue is obtained. In order to examine the thermal damage on the dental tissue, hardness and bending strength of the tissue are measured after being heated electrically at various temperatures. FEM thermal analysis is conducted to estimate the temperature distribution in a teeth and to discuss the influence of heat flux on the dental pulp. The results obtained are as follows. The appearance of the tissue begins to change at about 150°C and its hardness decreases with the increase of temperature. Its bending strength starts to decrease at about 50°C. Only the carious tissue can be removed from the cavity due to the large difference of energy absorptivity between the tissue and the carious one. It is possible to protect the dental pulp from thermal damage, because the temperature gradient in the teeth is very steep due to the small thermal conductivity of the dental tissue.

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Mechanism of locus error for contour following control of industrial articulated robot arms was analyzed and the locus error was derived theoretically. Main causes of locus error were found in the nonlinear transformation between kinematics and the inverse kinematics, and the delay of dynamics. The derived equation of the locus error was assured by simulation and experimental studies. Besides, the relationship between locus error and objective velocity was obtained by using the analyzed equation. As a result, objective velocity can be decided based on the maximum locus error and position loop gain of the servo controller. Moreover, optimal ratio of length of links was obtained by use of the derived relationship.

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For a camera system of tracking reflection markers, it is difficult to measure a motion of human fingers reliably and precisely, since occlusion of markers frequently occurs based on the concentration of them in a small measured space. On the other hand, the tactile sense is lost in a system using a glove and internal sensors. In order to solve these problems, a system is proposed which employs a commercial motion capture system and adds some improvements to it. Instead of a passive reflection marker, an LED is adopted. By machining the glass cover of it spherically, a non-directional marker is achieved. A method of preventing occlusion is newly proposed, in which a pair of four LED markers is attached to each finger and is successively emitted from one finger to an adjacent next finger. The sampling rate in case of applying this method is 50Hz for each finger. The accuracy for the dynamic joint angle is inspected and proved to be about 0.3° by measuring a motion of a pseudo finger link model. This accuracy is good compared with that of a glove system. For an example of a complicated finger motion, a manipulation of chopsticks is measured and the effectiveness of the developed system is experimentally confirmed.

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In this paper, the operating characteristics of thin TiNi shape memory alloy films are analyzed theoretically and a microactuator with one degree of freedom driven by two thin TiNi shape memory alloy films is designed and produced by way of trial. It is proved that the driving force of a microactuator made by TiNi shape memory alloy is caused by the bending moment generated from a shape memorized part of a thin TiNi film. And, it is found that the actuating velocity of thin TiNi films is reduced transitionally, and is under the influence of the velocity of temperature rise from As (start temperature of austenite transformation) to Af (finish temperature of austenite transformation). Furthermore, it is proved that the operating characteristics of microactuator can be designed based on the analyzing method shown by this report.

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This paper describes details of a set of robotic fingers driven by stepping motors. Robotic fingers need position, velocity and force control realized by stepping motor. New control system proposed in this study contains a generating system of real-time pulse series for driving stepping motor in the control loop. So, real-time sensor feedback can be achieved in the controlling stepping motor. When the robotic fingers complete a work as an operation, velocity controlled robotic fingers must change to the another control mode such as position or force control. This study treats a method how to provide force control to a robotic finger, and shows a method how to supply a sensor feedback to a stepping motor. It is found that a force controlled robotic finger shows a good performance of parts handling.

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The development of prototype of a new LPCVD using lamp heating and its study of the characteristics of polysilicon film deposited using this new LPCVD were reported. When a micro machine is produced using polysilicon film deposited with this equipment, we will need to know the electrical characteristic of this film. In the electrical characteristic, this time the resistivity and gage factor of boron doped polysilicon film deposited by a new LPCVD were measured. The comb motor as its application was tried to produce. The result of this study are summarized as follows; (1)The resisitivities of boron doped polysilicon are in range of 0.01-0.07Ωcm. These values of resistivity are available for micromachine devices as a micro actuator etc. (2)The gage factor of boron doped polysilicon are in range of 10-80. These values of gage factor are available for sensor device. (3) The trial production of comb motor was made and controlled in the displacement of 0-12.2μm with 0-220V.

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In this report, it is shown how leakage occurs from the seal that has not macroscopic clearance but has microscopic one through which no alkaline electrolyte can leak from the batteries as refused quality. The seal is made by nylon-gasket and copper of anode can surface. The copper surface of anode-can in the battery has electric potential almost equal to zinc potential, because it is contacted to the zinc anode materials. If the copper is zinc potential and alkaline electrolyte exists, hydrogen gas is generated on it. Generation of hydrogen gas on the modeled copper surface in the seal is confirmed experimentally. And leak speed through sealing which is modeled by pressed copper plate and nylon sheet is investigated. Pressure between copper plate and nylon sheet and surface roughness of the copper plate both of which concern cross section area of microscopic clearance between the plate and nylon sheet affect for the time that alkaline electrolyte leak through out from the seal model. In conclusion, generation of hydrogen gas in the seal is main cause of leakage and decrease of microscopic clearances is one of the most important ways for improving leak characteristics of silver oxide batteries.

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This study presents experimental results on machining of optical glasses by using ultra-precision lathe. Four machining types, which are subdivision of ductile and brittle modes, are defined for a minute description of experimental results. The machining experiment for BK7 was tested in several atmospheres. Damage-free cutting mark can be obtained within 1-micrometer tool infeed in methanol and ethanol atmosphere. An evidence for about 0.5 micrometer spring-back in BK7 was obtained from microscopic observation and experimental data. Results of the cutting several materials are presented and discussed. Comparing maximum depth of groove in the ductile mode and the critical depth of tool indentation calculated from previous theoretical analysis, it was revealed that nearly same amounts of depth are confirmed in SiC and vitreous silica, but that in BK7 is different from theoretical one in a figure.

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This paper describes the influence of grinding speed on the surface roughness of CVD diamond. Polycrystalline CVD diamond films coated on the ceramics pieces was ground by vitrified bonded diamond wheel of #1500. The surface roughness of CVD diamond films decreases from 0.14μmRmax to 0.07μmRmax when the wheel speed at grinding point increases from 314m/min to 1570 m/min. The temperature at grinding point was estimated. Relation between the temparature at grinding point and the surface roughness od CVD diamond films was linear. The temperature was over 750°C when the surface roughness was 0.07, μmRmax.

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It is very difficult to finish precisely the surface roughness of gear tooth to the extent of a few sub-micron meters by a grinding machine. Even if it is possible, a time for grinding tooth will be very long and a grinding bum may often occur. The authors have adopted a barreling process as a last finish process for improvement of the surface roughness of the ground or the shot peened gears. And they found that this process is very effective for improving only the surface roughness of gear tooth which may have a slightly tooth tip relief and/or crowning. In the present research, four kinds of gears which are the ground gear, the ground and shot peened one, the ground, shot peened and barreled one, and the shot peened and barreled one without grinding were prepared. Their surface durabilities were investigated using a gear testing machine which can measure the condition of oil film formation between a pair of gears during running. Though the tooth profile of the ground, shot peened and barreled gear did scarcely change after running, that of the ground and shot peened one changed remarkably. The duration of the oil film formation in a running test conducted using barreled gears was very good, but that of the ground and shot peened gears was very bad.

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This paper deals with an experimental investigation on damping characteristics of structures packed with balls. Test structures are square pipes packed with glass balls. The effects of impulse magnitude, square pipe dimensions and ball size on damping characteristics are investigated. The experiments show that the damping characteristics are markedly affected by the ball size and the damping capacity is improved by ball packing. It is also shown that the damping capacity is affected by packing arrangements, packing ratio and repulsion coefficient. The effective damping capacity improvement is achieved by remaining small space between packed balls and an inner surface of square pipe. This fact is confirmed by the experiment.

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This paper describes the simulation analysis of 3-dimensional cutting processes with chip breaker. The simulation method is based on dynamic-explicit elastic-plastic finite element method (FEM) and heat transfer FEM using forward Euler scheme, which are suitable for an FE model including a large number of nodes such as 3-dimensional problem. First, the turning processes with flat rake face tools have been simulated for the basic investigation into the effects of rake angle. In the results, the radius of chip up-curl, cutting force and temperature decrease, while the radius of chip side-curl increases with increasing rake angle. Secondly, the cutting process with the groove tool has been simulated. The results make it clear that the groove on the rake face decreases the cutting force and temperature, and it improves the machinability. In addition, the simulation results with changing the primary land width indicate that the difference of tool contact area with chip greatly influences the 3-dimensional chip shape.

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This study deals with the creation of ultraprecision microgrooves using non-rotational diamond tools mounted on an ultraprecision machining center. Two types of non-rotational V-shaped diamond tools with the same inclined angle of 90 degree were prepared, with rake angles of 0 and 10 degrees respectively. Microgroove machining experiments were conducted to find the value of the optimal cutting speed, changing the cutting speed from 5 mm/min to 100 mm/min. The optimal condition is judged by investigating the burr generation and shape of chips. Up to the total depth of cut of 10 pm, straight-shaped chips came out, and the surface roughness was good, although burrs were generated. On the other hand, with a total depth of cut up to 20μm, wave-like chips came out and a good surface roughness was obtained. In addition, no buns were found on the machined surface. However, the use of cutting fluid led to the generation of wave-like chips and no burrs up to the total depth of cut of 20μm. From the experimental results, it is found that the adequate cutting condition is that the rake angle is 0 degrees and cutting speed of 40 mm/min with the cutting fluid kerosene dripped. Using this cutting condition, cross, parallel and curved V-shaped microgrooves were machined. As a result, fine microgrooves were obtained, which are applicable to micro optical devices.

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Generally, for the position control of industrial machines, a semi-closed loop control which uses only the information of motor's angle is adopted, since it contributes to the stability of the control system. In this method, however, precise positioning cannot be attained because of the some non-linear elements in the driving mechanism. Also, by the full-closed loop control which uses only the information of load's angle, it is difficult to keep the stability because of containing a flexibility between the sensor and the actuator, so it is necessary to control the system at low gain, and the positional accuracy is declined. Therefore, this study shows a method of fusing a semi-closed loop control into a full-closed loop control, and this technique solves mutual faults which a semi-closed and a full-closed loop control have and it gets a high positional accuracy. Also, the effectivity about this control technique is shown by the experiment.

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A thermo-elastic-plastic finite element modeling of orthogonal cutting with a negative rake single-grit has been developed to understand the mechanics and thermal aspects of chip formation, which is the fundamental metal removal process of grinding. A stagnant chip material ahead of the tool tip, which is peculiar to the machining with a large negative rake, is introduced into the modeling to act like a built-up edge. This modeling coupled with temperature and strain-rate dependent flow stress characteristics of a work material SK-5 produces the serrated chips, which are usually observed experimentally under the cutting conditions of grinding region. There appear high and low temperature zones in turn according to severe and mild shear in the primary shear zone respectively. Simulations with and without a stagnant region show the importance of its role in the chip formation with a large negative rake. The shape of chip is affected by cutting speed and depth of cut; as Peclet number of deformation zone decreases with decreasing cutting speed or the depth of cut, serrated and long chips become difficult to form.

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The purpose of this investigation is to clarify the origin of the removal rate variation at the wafer edge in Chemical Mechanical Polishing (CMP) by using the floating head with the retaining ring. Within-wafer non-uniformity of removal rate is often determined by the removal rate variation at the wafer edge. Polished edge profile varies with the pressure distribution at the wafer edge. It is strongly affected by the pressure load applied on the retaining ring. Therefore, the non-uniformity of the pressure distribution at the retaining ring could result in the removal rate variation at the wafer edge. It is realized that the flatness of the retaining ring is very important factor for the polished edge profile variation. The same head with the same conditioned retaining ring gives almost the same removal rate variation at the wafer edge, even if the polishing condition is different.

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