Such a mechanism that the elements are bilaterally symmetrical with respect to the bisecting plane of driving and driven rotational axes is able to use as the constant velocity joint. The constant velocity joint that is composed of two circular-arc-contacting elements and the frame is most elementary one. The Rzeppa constant velocity joint is composed of several sets of the ball and two circular-arc grooves. The relative motion of the ball to each of two circular-arc grooves and the input-output relationship may be simulated by the circular-arc-bar constant velocity joint. The closed loop equation of the circular-arc-bar joint is given with any values of kinematic constants is deduced the quadratic equation. Sensitivities of linearity between input and output angles for errors of kinematic constants are calculated.

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A six-link slider-crank mechanism of the Stephenson type whose constitute four-bar mechanism is the double-crank mechanism is newly designed in order to reduce higher order components of the displacement of the slider. The space for moving links to occupy of this six-link mechanism nearly equal to that of the ordinary slider-crank mechanism. Kinematic analyses are performed and the shaking force and the shaking moment are analyzed. Calculated results are compared with those of the ordinary slider-crank mechanism and the six-link slider-crank mechanism whose constitute four-bar mechanism is the crank-rocker mechanism.

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To reduce the starting torque, an internal-spherical precession motion rotor type of orthogonal output type precession motion ball reducer is developed. In this report, the motion loci of balls on that internal-spherical rotor are analyzed. This rotor generates the precession motion which is similar to the conventional one. And using the evaluation method of a pressure angle, it is confirmed that rotor drives the driven rotor by over two balls. Also, the balls on this rotor which are assigned on the input fixed rotor side can be assigned on the arbitrary positions.

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Recently, the working fluid of hydraulic machines has been replaced from oil to water to reduce environmental problems. In order to solve the problems, the reduction of friction was tried using low viscosity oils and water. The serious problem of water or low viscous oils is their low loading capacity, even low viscosity, which causes the serious damage of the sliding surfaces. The application of surface texturing on the sliding surface is the promising method to reduce the friction. In this paper, we tired to introduce the surface texturing using EDM (electrical discharged machining), which made the isotropic random roughness. After removing the top peaks by polishing, several specimens with different surface height were prepared. When the friction for the specimens with surface texture were compared with that without the surface texture, the texturing could reduce the friction by 50 to 60%.

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Diamond-Like Carbon films (DLC films) show excellent tribological properties. Therefore, many industrial applications are going on in variety of products. In these applications, DLC coatings on soft substrate materials are one of the problems. It is a fatal problem that deformation of substrate causes cracks and delaminations of DLC films from substrate. In this study, "segment-structured DLC coating" has proposed to solve this issue. Deformation behavior and tribological properties of segment structured DLC films are discussed from the results of 4-point bending test and ball-on-disk test, respectively. From result of these tests, we derive criterion of segment-structured DLC film.

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This study investigated the characteristics in the undulation shapes of wear track profiles. Pin-on-disk tests involving boundary lubrication with certain materials and under specific conditions were conducted, with undulation profiles in the resulting wear tracks with many streaks therein being measured. An analysis of wavelets for these profiles showed that all profiles had similar characteristics (i.e., similar major undulation width or height/width ratio, regardless of materials or test conditions).

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Tribo-charging leads to spark discharges and causes various problems such as surface damages and oil degradation on metal bearings lubricated by oil. This study investigates the effect of the sliding velocity, v, viscosity, η, and load, L, on discharge of a steel/steel friction couple in poly-alpha-olefin. It has been identified that the amount of discharge is proportional to v^<14.1> η^<-2.90> L^<-0.0680> and high-current discharges increases at low load conditions.

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In this work, we gathered lubricating oils used in actual machines at random and collected contaminants on membrane filter. Using UV-VIS-NIR spectrophotometer, we studied diagnosis method by reflectance of contaminants caught on membrane filter and transmittance of lubricating oil, and we also used colorimetric analysis. We calculated average reflectance of a visible light wavelength and investigated relationships between average reflectance and transmittance at the wavelength of 496nm. As a result, we found there were differences in tendency by degradation grade of lubricating oil. The membrane patches of lubricating oils degraded by oxidation were colored brown and the change in average reflectance and transmittance was large. On the other hand, the membrane patches of lubricating oil contaminated by solid particle were colored gray or black and the change in average reflectance was large but the change in transmittance was little.

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Precise measurement of internal forces in constant velocity joints (CVJ) have recently become important in order to meet the requirements of lightweight, downsizing, and high efficiency. The internal forces of plunging CVJ have been clarified both theoretically and experimentally, and with respect to ball-fixed CVJ, its internal forces have been analyzed by employing a dynamic numerical simulation. Although experimental verification has not been achieved yet. In this study, a new test rig is developed in order to measure the internal forces acting in a ball fixed CVJ. The measurement are in good agreement with those obtained by the numerical simulation Additionally, we demonstrate the influence of friction force on internal forces.

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We have developed a new type of three-dimentional measuring instrument consisting of a laser distancemeter and two flat mirros rotated by ultrasonic motors under control of a micro computer. The laser distancemeter used has a measuring accuracy of 3.0mm over a distance from 0.3m to 100m. This developed equipment can measure a three-dimentional coordinate of any single point. Performance of this equipment was evaluated by measurring the three dimentional coordinate data on the wall which is 6m or 36m distant. The effects of the ultrasonic motors and the flat mirrors on the mesuring accuracy were examined.

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A new technique has been developed for investigating into the physical properties of loaded boundary films between metal surfaces, in which mercury is used as a counter surface of a steel surface for minimizing the effects of the individually different topographies of solid surfaces. An oil film is loaded by squeezing the steel surface into mercury, and the time evolutions of film thickness and coverage are obtained simultaneously by the complex impedance analysis with an equivalent electrical circuit. The loaded film of hexadecane is drained down to a thickness about 2nm with decreasing coverage from unity to zero, in which a dependent relationship is found between film thickness and coverage. The addition of 0.01 wt% palmitic acid into hexadecane forms an explicit residual film with a thickness about a few micrometers and a coverage of unity, which has an ability to support a mean pressure about 0.1kPa without any hydrodynamic effects.

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In order to reduce the environmental burden,low viscosity oils have been required applying for engines. However, the excessive low viscosity oil causes the increase of friction and wear. Therefore, the lower limit exists for application. In general, it is said that there is an effect of graphite to decrease the friction and wear in cast iron. However, the literatures that logically explained this common sense are few. In this study, The aime of this paper is to clarify low viscosity limit with block on cylinder type tribomater and to analyze composition with EPMA and XPS. The wear mechanism was discussed from the viewpoint of an effect of graphite. The region where specific wear rate is small narrows with low viscosity in PV-diagram. By analyzing XPS, it could be confirmed that a relative carbon content on wear surfaces increased more than non-wear surfaces.

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In order to achieve a magnetic recording density of 1 Tb/in^2, the spacing is expected to be less than 2-3nm. However, a critical issue in achieving such an ultra-low spacing is the dynamic instability of the head disk interface (HDI).The goal of this research is to clarify the effects of the lubricant film thickness as well as the lubricant materials on slider hysteresis behavior in detail. In this study, the difference in the touchdown velocities was monitored by varying the lubricant film thickness and lubricant film materials of the disks ; further, the correlation between the observed phenomenon and the variation in the experimental parameters was investigated. Considering the obtained experimental results, it was suggested that the variation in the touchdown velocity is due to a variation in the intermolecular forces.

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To clarify the effect of shearing strength on superlow friction mechanism of CNx coating, we compared between adhesive forces of Si_3N_4 AFM stylus to the surface of as-deposited CNx and wear track of CNx which showed friction lower than 0.01. Then, we investigated the effect of N_2 gas on the adhesive force of these surfaces, when N_2 gas was supplied to contact interface during measuring the adhesive forces. (1) The wear track of CNx which showed low friction in N_2 provided relatively lower adhesive force under N_2 blowing condition than under O_2 blowing condition. However, it was clear that the adhesive force of the wear track in air was almost the same as that of as-deposited surface. (2) The surface roughness of the wear track decreased after sliding in N_2. However, we could not obtain obvious difference between the adhesive force of the wear track and that of the as-deposited surface in air.

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The relationships between sliding speeds and frictions on two contacting surfaces in the lubricant are well known as Stribeck curve, and it is divided roughly into three modes of lubrication. In this research, the micro-vibrations of the vertical direction to the contacting surfaces are given to the pin of the pin on desk machine, and the influence of those vibrations on the modes is examined. The displacement of the vibrations 0-2μm and the frequency 0-5kHz are given. A contact voltage, a dynamic load and friction between the pin and the desk are measured. It is clear that the larger the displacement and the frequency of the vibration of the pin are, the smaller the friction and the surface damage of the desk are.

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In order to design the Ultrasonic motor (USM) which provides higher performance to be responsible to various specifications, it is indispensable to understand and control friction drive force properties at the contact interface between driven rail and drive tip of the USM. Furthermore, an evaluation parameter for frictional drive force of the USM has been strongly required. In this research, by using newly developed method, frictional driving force of the USM and relative micro slip at the contact interface between the pin and the rail during operating the USM were successfully measured for the first time in the world. Usefulness of "tangential force per unit relative micro slip distance", which was calculated from the measured values mentioned above, was proved as evaluation parameter for the frictional drive force of the USM.

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Lubrication is one of the most important key technologies for the reliability and long life of space mechanisms. Solid lubricants, which are pre-coated on the earth by a certain amount thickness, are commonly used as present lubrication. Therefore, the life of the lubricant is determined by its wear. To extend the lifetime, a new lubrication method for on-demand and in-situ restoration of the lubricants called as "Tribo-coating" had been introduced, and its effectiveness as practical solid lubrication method has been clearly shown. The ultimate objective of this series of studies is to develop a self-restored lubrication system with the Tribo-coating. In this paper, the world smallest evaporation source of tribo-coating for self-restored lubrication system was developed. The power needed for evaporation of the solid lubricant with the developed MES was 560mW. And sufficiently low for practical use friction coefficient of 0.005 was obtained with ball bearing coated by Tribo-coating with the developed MES.

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Oil film reduction caused by starvation is observed in rolling element bearing lubricated with grease or lubricated by an oil and air lubricating system. Empirical formula for starvation factor, which can predict the oil film thickness in starved EHL condition, is obtained from measurements of non-contact time fraction using a thrust ball bearing. In order to verify availability of this formula, torque measurements for an angular contact ball bearing are conducted in starved conditions. It is suggested that the degree of the starved EHL film formation can be estimated by the obtained formula independent of the bearing size and bearing type in a relatively low speed condition.

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A lot of problems by electric pitting of small ball bearings have come to be shown in recent years. A lot of research on electric pitting of bearings for railroad vehicles have been done, but there is little research for the small ball bearings. This is a basic experiment of electric pitting for small ball bearings (608), and this research showed that electric pitting occurred below the measure of current density of electric pitting generated by past research.

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In this paper, we researched the accurate examination of two methods regulated by Japanese Industrial Standard for rotational accuracy of Rolling Bearings. We produced two measuring apparatus based on JIS and measured radial accuracy of angular contact ball bearing in various conditions. The results are summarized as follows: (1)The evaluation method in JIS had large dispersion. (2)The influence of the measuring conditions on radial run-out was very big. It was necessary for unify the measuring conditions in order to evaluate the radial accuracy of rolling bearings. (3)Comparing results of two methods, accuracy of method 2 is better than that of method 1.

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In late years, many inverters (a variable voltage, a variable frequency control unit) are used with the air conditioner and the Uninterruptible Power Supply (UPS) etc. An electric corrosion occur to the bearing in the cooling fan used near the inverter happens frequently. This phenomenon is assumed a cause that a slight current is generated by the high frequency noise caused by the inverter, and the current flows to the bearing in long time. A lot of researches on electric pitting of bearings for the railroad vehicles have been done, but there is little research intended for the small ball bearings. In this research, the bearing characteristic when it is assumed to be a final purpose to investigate the cause in which the high frequency stray current corrosion happens, and rotates the bearing in the high frequency environment is examined. This is a basic experiment of electric pitting without turning on electricity for small ball bearings (693).

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Aerodynamic journal bearings have been successively applied to high speed laser scanner motors. In these devices, herringbone grooved aerodynamic bearings are usually used due to their excellent stiffness and stability at high speeds. However, there is a disadvantage that it is slightly difficult to make herringborn grooves on the shaft surface, which raises the manufacturing cost. In this paper, a newly designed aerodynamic journal bearing with diagonal grooves is proposed which is much easier to make than the conventional herringborn bearings. The static and dynamic characteristics of the proposed bearing are investigated theoretically and experimentally.

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A FEM software specializing in analysis of gear pair has been developed. In the software, a new non-conventional element ; tooth flank film element, is applied to give easily boundary conditions between contacting tooth flanks. The purpose of the present study is to confirm the usefulness of the developed software ; i.e., validity of the tooth flank film element. For this purpose, the calculated distribution of contact stress between tooth flanks was compared with the measured one. A pressure measurement film is used for measuring the contact stress. However, the film alters the boundary condition near the contact point, because its Young's modulus is much smaller than that of steel. In the FEA, therefore, Young's modulus of the tooth flank film element was set to be identical to that of the pressure measurement film. As a result, the calculated and measured stress showed good agreement.

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The present paper describes fatigue tests of plastic gears under high temperature. A test rig with high power has been developed to enable tests to be performed under large torque and high rotation speed. At the present, fatigue tests are performed only for natural PA46 gears ; i.e., non-reinforced gears. Therefore, applied torque is not so large, but rotation speed is high. As a result, when the applied torque is not so large, POM gears show higher strength than PA gears. When the applied torque becomes larger, PA46 gears show higher strength than POM and PA66 gears. This result would come from good tribological properties of PA46 material which can realize low friction between tooth flanks.

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In these days, the damage diagnosis from remote administration is demanded as an example of maintenance business. For the reason, many researches have dealt with a damage diagnosis on tooth surface of gears by using vibration or noise data. However, this diagnosis method is difficult to detect an abnormal tooth early on. Therefore, we develop a method to diagnose by using a laser beam from the point of view of remote diagnosis. Our method can be explained as follows. First, a tooth surface is irradiated by a zonal laser beam from oblique direction, and then an irradiated laser beam line is shifted along the height of tooth according to gear revolution. The variations of laser reflection between the initial and the present conditions are compared, and it can estimate a condition on tooth surface such as initial or abnormal abrasion, pitting, spalling, etc. To confirm the validity of our method, pitting experiment was carried out, and at the same time the laser reflection was measured with vibration and noise. As a result, the data of laser reflection revealed occurrence of the pitting more apparently and earlier than that of vibration and noise. Thus, it can be concluded that our method can accurately estimate the condition of tooth surface and sufficiently assess the duration of the gear's life.

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Crack length measurement and crack initiation detection in a fatigue process are extremely important techniques in the researches for the investigation of crack growth characteristics and the fatigue strength evaluation of machine elements. The purpose of this research is to show a simple and high precision method to measure the length of a crack as well as a micro crack using an extremely thin ion sputtered film. A grid pattern ion sputtered film was proposed to measure the crack length for a bending test specimen. Based on the comparisons between the measurement results and that by a microscope, it was clarified that the grid pattern ion sputtered film has a very high measurement precision. This method should be invaluable and practicable for the crack length measurement of insulating materials such as ceramics.

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The manufacture and performance of case-carburized gears were investigated from the result of roller tests which simulated gear tooth contact. First, the rolling-sliding contact surface of various processing case-carburized steels was observed by using a scanning electron microscopy (SEM). Secondly, the relation between surface hardness and surface failure was studied. On the rolling-sliding contact surface of the tempered steel, the subzero treated and tempered steel, the tempered and shot peened steel, and, the subzero treated, tempered and shot peened steel, the following results are obtained: (1) In the case of low load condition, cracks and micropits occur between grinding grooves. (2) Under a heavy load, the grinding grooves disappear completely, then, cracks, micropits, small pits, pits and spalls occur. (3) Even though the case-carburized surface is hardened by subzero treatment and shot peening, the wear and surface fatigue are not improved.

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A rolling contact fatigue test was carried out under a traction oil lubricating condition and the test result was compared with that under a turbine oil lubricating condition. The minimum film thicknesses under both lubricating conditions were almost equal. The failure mode of both lubricating conditions was pitting caused by surface cracking. The rolling contact fatigue strength under the traction oil lubricating condition was greater than that under the turbine oil lubricating condition. The cracks observed on the roller surfaces tested under the traction oil lubricating condition were the longer along the axial direction of the rollers.

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Austempered Ductile Iron (ADI), which has much the same strength and toughness as usual steels, has been developed. ADI has many advantages in mechanical properties and manufacturing, for example, weight reduction due to smaller density than that of steel, good properties of vibration and noise, low cost in machining and heat treatment of blanks due to near-net-shape casting. It has been reported that ADI can be sufficiently applied as a medium hardness gear material. Recently, two steps bending phenomenon of S-N curve for the bending fatigue strength of ADI is reported, and the fatigue phenomenon in long life region over 10,000,000 time number of cycles is discussed. However, the surface durability in long life region has not been clarified until now. In this paper, surface durability of ADI rollers in long life region is investigated using a disk machine which simulates the rolling and sliding action of gears. Furthermore, fatigue limit for surface durability of ADI is estimated by observations with crack initiation and propagation.

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The effect of shot-peening on tooth surface strength of carburized gears has not been clarified because of its complicated mechanism. Micro pitting was caused by the load that was lower than spalling appeared in hardened gears. And micro pitting becomes the trigger of serious accident to be tooth breakage etc. In this study, the authors investigated the generation mechanism of micro pitting and the effect of shot-peening was investigated by using the stress analysis. As a result of theoretical analysis, extremely high maximum shearing stress was caused in the contact surface. Therefore, micro pitting was caused from the surface originated crack caused by extremely high shearing stress at real contact area. D value that is the index of contact condition strongly influence the occurrence of micro pitting and that influence is the same as the thermally refined steel gears. Also, the influence of the shot peening takes part in the form of the compressive residual stress when the stress is analyzed and surface roughness of the contact surface when D value was calculated.

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In order to investigate the influence of peening on the fatigue life of steel gears, the steel rollers and gears cavitation shotless peened and shot peened with different conditions were fatigue-tested using a roller testing machine and a gear testing machine. The hardness and the compressive residual stress of test rollers and gears increased by these peenings. The surface roughness of those increased by the shot peening, whereas those did not increase so much by the cavitation shotless peening. In the fatigue tests, the fatigue life of most shot peened gears was as long as that of the non peend gear in this experimental range. On the other hand, the fatigue life of most cavitation shotless peened rollers and gears was longer than that of the non peend roller and gear. It follows from these that the cavitation shotless peening is good for the increase in fatigue life of steel gears, because the surface roughness does not increase so much by cavitation shotless peening.

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This paper presents a study on residual stresses and bending fatigue strengths of case-carburized thin-rimmed spur gears with web arrangement. A heat conduction analysis and an elastic-plastic stress analysis during the case-carburizing process of the thin-rimmed spur gears with web arrangement were carried out for various case-carburizing conditions by means of the case-carburizing simulator developed by the authors. Bending fatigue tests were carried out for different case-carburized thin-rimmed spur gears with web arrangement. Effects of the case depth, carburized part and web structure on the residual stress and the bending fatigue strength were determined. Furthermore, results for the case-carburized thin-rimmed spur gears with web arrangement were compared with those for solid gears.

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A pin-rack gear mechanism, which consists of a rack-bar and a sprocket pinion, transforms a rotation motion into a liner one. The rack-bar has a series of pin train, and meshes with the sprocket pinion. We measured the root stress of the sprocket pinion, the driving torque, and the horizontal force of the rack bar using a pin-rack gear mechanism testing machine. Additionally, we calculated the root stress of sprocket pinion, the contact stress on the tooth surface, and the PV value. We considered the strength of the pin-rack gear mechanism comparing the measured data with the calculated results.

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Usually the design of hypoid gear is more difficult than helical gear because it uses different theoretical tooth flank that is described by individual machine setting and cutter specification for each gear. This research developed a new design and analysis system for both of face-mill and face-hob type hypoid gears. The new design system consists of five parts: (1) basic dimension calculation, (2) cutting machine setting, (3) simulation of 3-D theoretical tooth flank, (4) TCA of theoretical tooth flank, (5) Real TCA of actual tooth flank. The machine setting of this paper based on the basic relationship between the pitch cones and assembly dimensions, is compatible to the conventional Gleason system. Especially, the analyzed tooth contact pattern of the soft tooth flank just after cutting or the lapped hard tooth flank after heat-treatment agreed well to each measured result, respectively.

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Numerical data are calculated and used for CAD/CAM Systems for hypoid gears. New idea for crowning of tooth surface to obtain point contact for hypoid gears is proposed. Tested contact mark on the tooth surfaces of hypoid gear coincide well with the theoretical contact pattern estimated by 3D/CAD drawing and also numerical tooth contact analysis.

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The hypoid-gear having great freedom of design has high possibilities of performance. The author has developed the assistant software for design and manufacturing to derive them. This paper describes it's utility to grasp the basic performance in the design stage. Moreover it presents the analysis of lapping process, which is very important to make gears of quiet operation, for the gears cut by a small cutter. The predominance of swing method lapping toward the EP method lapping is suggested.

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A hobbing method for a face gear meshing with a worm-like pinion is proposed. The hobbing is made in 4 processes during one rotation of the hob. To realize the proposed method, an NC gear-cutting machine with 4 control axes was designed and made. Meshing tests using the face gear finished with the developed gear-cutting machine were conducted. As the results, the good tooth contact patterns were obtained.

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A simplified method to analyze meshing of worm gears with modified tooth surfaces is proposed. The contact patterns and contact stresses are calculated using the previously developed program for helical gears by replacing meshing of the worm gears to that of the helical gears. The usefulness of the method was confirmed by the tooth bearing tests.

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The purpose of this research aims at practical use of the concave conical gear. Tool to generate concave conical gear is not a straight rack but also a conical-shaped wheel. This conical-shaped wheel is realized imaginarily, and this is called a "imaginary conical-shaped wheel". In this paper, first the characteristic of involute hob is demonstrated, and the hob helicoid is defined. This imaginary conical-shaped wheel is obtained as enveloping surface of the hob helicoid in anti-crowning motion. Secondly, the hobbing method for helical concave conical gear is developed, based on the generating method. Finally the helical concave conical gears are made for trial. Tooth surface of the test gears are measured and compared with theoretical ones. Both tooth surfaces are in good agreement.

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In this study, we call an internal gear having conical angle as the internal conical gear. In the case of conjugating with spur gear, this gear can transmit rotational motion between intersecting shafts. Also in the case of conjugating with conical gear, there is possibility of adjusting backlash by axial movement. Therefore, as a first step of the study we obtain theoretical tooth surface of the internal conical gear cut by gear shaper. Next we measured tooth surface of the test gears and compared them with theoretical one. Finally the tooth-bearing test confirms that theoretical analyses holds true.

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The design and production system of the standard conical involute gear has been developed. But the addendum modified conical involute gear with deep tooth depth is not studied in detail. We had reported a new design method for profile shifted conical gear. Now, a production system for the addendum modified conical gear with deep tooth depth is shown in this paper. A profile shifted conical gear production is same system as a conventional conical gear production, exept the calculation of the horizontal feed and the spacewidth angle on base circle. Several typical test gears are manufactured. As a result, the tooth profile of the manufactured tested gears are in good agreement with the theoretical one. Thus, it is proven that this production system has the applicability.

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This paper proposed a new design method based on the theory of nonintersecting bevel gear such as hypoid gear, to decide the mounting dimensions of the profiled shifted conical involute gears. The profile shifted conical involute gears are meshed at the designed pitch point that is not the standard pitch point. Test gears are designed and made for trial. Path of contact between tooth surfaces of conical involute gears is obtained. Finally, tooth bearing tests are performed. Test results of tooth bearing are almost agreement with the theoretical one. Thus, it is proven that this designing method has the applicability, and this new type of gear has possibility to be used in near future.

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In this paper, we report a new type of nutation motor, named the OFD type pneumatic nutation motor consisting of a diaphragm which has some pneumatic rooms, a nutant bevel gear and a fixed bevel gear. Injecting air into each pneumatic room sequentially causes nutation of the nutant bevel gear, which makes the output shaft to rotate through the universal joint and spherical bearing. In this report, first, the driving principle and design of this motor are presented. Next, the prototype of the OFD type pneumatic nutation motor is fabricated and tested. As a result, it is demonstrated that the OFD type nutation motor is (1) small-sized, (2) simple structure and (3) highly durable.

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The planetary gear unit with torque limiter mechanism was developed for the purpose of protecting a DC motor. When overload occurs in the output shaft of the gear unit, a rotary internal gear maintained with friction parts and springs, a DC motor can continue turning. In this report, first, the driving principle and design of this gear unit are presented. Next, its characteristics are analyzed theoretically. The prototype of the planetary gear unit with torque limiter mechanism is fabricated and tested. As a result, it is confirmed that this gear unit has a highly durable.

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We have developed three port electromagnetic valve for micro reactor. This study aims at integrating the micro three port valve into micro reactor or several micro flow control systems. For that purpose we developed the micro three port valve with actuator mechanism. Electromagnetic actuators have big power in millimeter scale in general, and achieve high response speed. We designed and manufactured micro three port valve which has a moving part of magnet. We applied the developed valve to make slug flow (two-phase flow) by pouring two liquid into this valve's ports to realize efficient promoting chemical reaction.

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This paper discusses the development and control of the master-slave system capable of grasping an object even when coefficient of static friction is unknown. Partial slip information is known to be essential for conducting stable grasping in a teleoperating system. The developed sensor contains strain gages in several ridges placed on the curvature contact surface. By measuring strain velocity of each ridge, the vibration which occurs due to a partial slip can be detected. We developed the master-slave system with the slave robot which uses the developed sensor to detect a partial slip and automatically controls grasping force. Through the grasp manipulation experiment, the validity of the developed system was confirmed.

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The performance of some machine essentially depends on actuators. But, the processes of micro sized structures are very difficult. On the other hand, the LIGA process can be used to fabricate nano- and micro- scale structure. Then, we have manufactured a nine part operation expose stage. Thus, this exposure stage has made three-dimensional deep X-ray lithography possible. With this technique, we have fabricated a high aspect ratio coil for solenoidal electromagnetically driven actuators. By using this technique, a coil consisting of 10μm lines and spaces with an aspect ratio of about 5 can be manufactured. This actuator is expected to provide enhanced output suction force, in spite of miniature size.

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We are studying a two-axis micro-actuator to enhance the presentation reality of a tactile display that is capable of presenting pressure distribution and shearing force. The actuator is composed of sequentially connected x- and y-directional actuators ; each actuator is comprised of bimorph piezoelectric actuators. The x- and y-directional actuators are independently controlled by changing the applied voltage to position a probe that is attached to the tip of a two-axial actuator. The maximum displacement and force generated by the x-directional actuator are 1.1mm and 0.03N, respectively. Those generated by y-directional actuator are 1.0mm and 0.06N, respectively. Since relationship between applied voltage and displacement caused by the voltage shows a hysteresis loop in the bimorph actuator used as components of the two-axis actuator, we produce a control system for the two-axial actuator based on a multi-layered artificial neural network to compensate the hysteresis.

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A newly developed linear electrostatic microactuator is described. Thus far, authors have proposed an electrostatic linear microactuator with vibrating motion in order to avoid the influence of the friction. Satisfactory characteristics are achieved about low energy consumption, output force, moving speed, and positional accuracy. However, there are several difficulties about putting it into practical use. Fabrication cost is very high, and it is hard to produce in large quantities. To clear up these problems, the factor analysis about output force is done.

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