Estimation method of optimal mount positions of inertial sensor for thigh and crus is described. These positions are estimated by calculating the movement of reflective markers placed on the skin with relative to femoral or tibial coordinate system. A Point Cluster Method that derives limb segment motion using plural reflective markers is employed to calculation the movement of markers on the limbs. The movement of markers is evaluated as displacement and rotation, and the marker position where these values are minimum is estimated as optimal mount position. Five experimental movements assuming physical exercise were given to five subjects: flexion/extension of knee, counterclockwise rotation of waist (external rotation of tibia), clockwise rotation of waist (internal rotation of tibia), flexion of knee medially (flexion of knee and valgus of tibia and ext.rot. of tibia), and flexion of knee laterally (flexion of knee and varus of tibia and int.rot. of tibia). The experimental results show that estimated optimal mount positions are middle position of anterior aspect of thigh and inferior position of anterior aspect of crus.

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One of the main issues in the development of printers is to achieve sheet-feeding stability with various kinds of sheets and to shorten the development period. In recent years, studies on sheet handling mechanisms have been performed that enable us to develop a sheet-feeding path efficiently; however, defects resulting from sheet-feeding instability still occur because many defects cannot be treated analytically. To achieve efficient development condition of printers, mechanism analysis of the paper-wrinkle generation phenomena in fuser unit has been conducted. A convenient geometry model of the paper-wrinkle has been constructed based on the observation of the generation process, and the wave slope angle as an alternative characteristic of the wrinkle generation has been derived. In addition, principle analysis equipment has been developed to measure the paper feeding velocity distribution and the transformation of the deformed paper. As a result, relationship between the roller shape and the generation process of the paper-wrinkle has been evaluated quantitatively, and the validity of the wave slope angle as the alternative characteristic has been verified.

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The fixed points theory is applied for the dynamic absorber attached to two degree of freedom system which consists of two identical single degree of freedom systems connected in series. The frequencies of fixed points and the ratio of natural frequencies to equalize the amplitudes at fixed points are analytically derived, in case that the responses at fixed points are in phase. The damping coefficients which make fixed points extremal value are also obtained. Because each of fixed points has different optimal damping coefficient, representative value must be determined. Arithmetic and geometric means of the damping coefficients are considered, and the comparison of the frequency response functions show that the geometric mean is suitable. The analytical solution is compared to the numerically computed results whose responses at fixed points of equal amplitudes are π rad out of phase, and it is shown that these dynamic absorbers have almost same performance of vibration suppression.

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Preventing brake squeal is a significant task in brake development because brake squeal bothers users, thereby reducing a vehicle's commercial value. Many researchers have tried to find the mechanisms that cause brake squeal, so the number of complaint to brake squeal is declining. However, brake squeal sometimes appears after a vehicle has been in use for years even though it was not generated early in the vehicle's life. In order to enable people to use vehicles for a long time with a high satisfaction level, it is important to find the factor that causes brake squeal to arise gradually because of specific changes; so we focused on the stiffness of brake pads, which are always wearing during braking, because the pads' stiffness correlates with brake squeal. This study presents the influence of pads' surface texture on disk brake squeal. Pads with different surface texture were prepared by changing the braking time and machining. We measured the pads' stiffness, which we evaluated by exciting a pad at the frequency and vibration amplitude that cause brake squeal. The measurement results show that pads' stiffness increases as their surface becomes smoother, which means that the surface stiffness of pad influences the pads' stiffness. Finally, we used a numerical model to analyze the generation of squeal, which is caused by pads' surface texture.

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The authors have developed a vibration suppression system with variable vertical oil dampers in primary or secondary suspensions of railway vehicles for improvement of riding comfort due to vertical vibration. In order to apply this system into practical use, the function to detect the failure and stop the control in case some damper fails is required. This paper presents a technique for damper fault detection based on the phase difference between the bounce and the pitch vibration of bogie frames or car bodies obtained with inertial sensors, as a method without mounting sensors in oil dampers. The result of vibration excitation test with one vehicle on a testing plant demonstrates the fault of a primary vertical damper was detectable by evaluating the phase difference between the bounce and the pitch vibration of the bogie frames. The result of running test in a meter-gauge line demonstrated the fault of a secondary vertical damper was detectable based on the phase difference of that of car bodies. These results have suggested the proposed method is effective for the fault detection of both primary and secondary vertical damper.

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In order to apply acoustic energy to industrial fields, its amplification is essential and vibroacoustic coupling is one of best ways of amplifying acoustic energy. In the present study, we consider a cylindrical structure with thin plate at both ends and investigate vibroacousitc coupling between the plate vibrations and internal sound field when an external harmonic force is applied to one end plate, regarding such a coupling phenomena as one of the available measures to amplify acoustic energy. This coupling is theoretically and experimentally investigated by considering the behavior of both plates and the acoustic characteristics of the internal sound field for varying dimensions of the end plates and the cylinder. In the analytical model, the end plates are supported circumferentially by springs in order to obtain support conditions that are as close as possible to the actual condition in the experiment due to adjustments of spring stiffnesses. The cylinder length and phase difference, which maximized the sound pressure level inside the cavity, are clarified theoretically. These theoretically results are verified experimentally through an excitation experiment using an experimental apparatus that is emulated by the analytical model. The above-describe results reveal such a vibroacoustic coupling phenomenon is useful for the amplification of the acoustic energy.

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In this study, a virtual sound production system is developed where the difference frequency component appears as the secondary audible sound at a point of interference locally by the nonlinear interaction of two independently radiated ultrasounds while they travel directionally and intersect each other. The design of high-directive ultrasonic radiator, followed by the investigation of virtual sound production performance has been done theoretically as well as experimentally. It is known from these investigations that the fairly local sound reproduction in free space is possible, yet the sound pressure level of the secondary field is small. The results have also shown that the generated virtual sound area is dependent on both the difference frequency and the intersection angle of two carrier waves emitted by two sound sources.

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When elevators travel at high speed, horizontal vibrations of the car tend to be set up by guide rail deformation. Therefore, it is important to identify the deformation accurately to improve ride quality. In this paper, we discuss a method for estimating the rail deformation by an inverse transfer function and operational acceleration data. The acceleration data indicates the vibration caused by both the rail deformation and external forces acting on the car, that is, the rope sway and wind pressure excite the car directly when it is moving by a counter weight. To identify the rail deformation from these data accurately, we propose an elevator model that has guide levers and a car. Moreover, the estimation error occurs when accelerometers are installed inaccurately. To avoid this error, the weighting function based on the modal vector is also introduced. The validity of the method is shown by the simulations and experiments.

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In recent year, it is reported that roll and lateral vehicle motions are affected by the road input, and the characteristic of vehicle motions changes depending on the vehicle speed. However, there are few researches about a suspension control method which takes into consideration with the suspension characteristic that is the toe change and scuff caused by suspension stroke and tire side-force. In this paper, new active suspension control method is proposed to reduce the vehicle vibration and vehicle lateral motion due to the road input. Firstly, a vehicle model including the suspension characteristic is constructed. Next, the time delay of the road input from the front wheel to the rear wheel is modeled with Pade approximation. Then we formulate the linear parameter varying system taking amount of vehicle speed. The gain-scheduling controller based on the linear matrix inequalities which sets the lateral acceleration of the vehicle to one of controlled outputs is proposed. Finally, in order to verify the effectiveness of the proposed control method, the simulation is carried out by using the full vehicle model. From the result, it was confirmed that the proposed gain-scheduling controller can reduce the vertical and lateral motions caused by road disturbance at a different vehicle speed better than a normal H_∞ controller.

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Demands to vehicles performance from environmental view points are growing these days. Lightening each part is needed as one method to improve the Fuel Economy of the car. The main role of brakes is to transfer the kinematic energy of the vehicle to the dissipative thermal energy, and accordingly to lead the deceleration of the vehicle. On the other hand, a steady braking performance is important because it drives comfortably. The appropriate design of brakes for the stable performance requires the understanding of the temperature distribution based on the analysis of heat transfer. The friction force in a brake system is generated by making contact of the pad with the rotor. This study presumed that the friction force is depending upon the temperature of the surface where the pad and rotor come in contact. This study proposed a calculation method for estimating the temperature of the friction surface. Moreover, this study conducted the experiments to compare with the estimates from the proposed method. The experimental results agree with the estimations calculated from the proposed method. Based on the temperature distribution calculated by this method, considering how the shapes of the pad have an influence on the generated brake force.

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Electro-magnetic actuators have potentials of sensor-less vibration control due to the abilities of simultaneous actuation and sensing. This paper discusses a method of the electro-magnetic shunt damping with a digital virtual impedance circuit realizing a resistor or a resistor-capacitor circuit optimally designed by a theory of tuned mass damper. The digital virtual impedance circuit, which consists of a controlled voltage source and a computer, can realize arbitrary impedance. Using the virtual impedance concept, the optimally tuned resistive component which might have negative value can be realized, even though the conventional passive electro-magnetic shunt damping technique suffers from performance degradation due to the inherent resistance of the coli. The experimental results demonstrate the effectiveness of the proposed method. From the analysis of the open-loop transfer function, we also discuss the stability margin of the system and the suitability of the virtual impedance applied to the electro-magnetic shunt.

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Magnetic bearing motors have the advantages of no friction loss, no lubrication, and so on. However, these motors are not used widely because of their high cost and large size. To overcome these limitations, a self-bearing motor having a simple structure with distributed windings has been proposed. The rotor consists of a permanent magnet and an iron yoke that rotates within the body. The stator consists of a six-phase distributed winding and is installed between the permanent magnet and the back yoke of the rotor. A Lorentz force, generated by the interaction between the stator current and the magnetic field of the permanent magnet, controls the rotational speed and radial position of the rotor. In this paper, a closed-loop torque controller with rotational speed feedback is introduced, and the performance of the controller is verified experimentally. The rotor was able to avhieve speeds of up to 10,000 rpm, which is approximately twice the rotational speed achieved in a previous study. Moreover the dynamic torque and motor efficiency are determined, and the characteristics of the proposed motor are discussed.

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An accelerometer has direction gaps between the package and the actual sensors in general. Conventional calibration methods of accelerometer, e.g. ISO standard, do not consider this direction gap. This study proposes a new calibration method. The method uses a new examination system with parallel link exciter mechanism. The exciter rotates a target accelerometer in a uniform circular motion and the posture of the accelerometer is kept constant against external coordinates. The required torque for the rotation is small and constant because the rotation components are balanced with counter weights. Therefore, the exciter applies a stable sine wave acceleration to the accelerometer. This method contributes not only the accuracy of input acceleration but also removing offset noise. In addition, the input acceleration is calculated only by one differential computation whereas ordinary mechanism requires second order differential. From the accelerometer output, a plane including actual sensor direction is detected by the sine curve profile. The direction of actual sensor is the line of inter section of two measured planes. For a 3-axis accelerometer, 2 times measurement is enough to determine all actual sensor directions and sensitivities with this method (1 time measurement is enough for a 2-axis accelerometer). Actual sensor directions and sensitivities are experimentally examined. The result is consistent with the data sheet of test accelerometer.

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In medical and cosmetic fields, skin color and texture have not been investigated quantitatively so far despite of the importance. Ordinarily, melanin is produced increasingly due to excessive stimulus such as ultraviolet rays, and excessive melanin causes pigmentation such as spots and freckles. Therefore, since melanin pigmentation is one of the important barometers to express skin color and texture, we focus on estimating quantity and uniformity of melanin in corneocyte for quantitative analysis of skin texture. Extraction methods of melanin by image processing have been developed and then quantitative indices obtained through image processing have been proposed. By using multiple linear regression analysis, we find that visual appreciation score about quantity and uniformity of melanin by human expert is highly predictable by using these quantitative indices. Though human expert takes much time to score, proposed method is able to shorten the amount of time remarkably, and it comes into practical use since June 2010.

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We have already confirmed the importance of embodied sharing in avatar-mediated communication and have demonstrated the effectiveness of the entrained nodding responses for human interaction and communication support. In this paper, in order to support the avatar-mediated communication, a virtual audience system is developed by using a speech-driven embodied entrainment picture in which interactive CG objects behave as listeners such as nodding responses. This system provides a communication environment in which not only avatars but also the CG objects placed around the avatars are related to embodied communication. By using this system, the effectiveness of the present system in supporting embodied communication has been demonstrated by carrying out a sensory evaluation and a speech-overlap analysis for 20 pairs of 40 talkers.

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Rehabilitation for upper limbs is important for elderly people, people who have suffered a stroke and so on. In recent years, the needs for rehabilitation support systems are increasing, which use force display system. Especially, the application of a passive-type force display system is desirable for its high safety. However, there are some directions and link positions for which it is difficult to display the force in a passive-type force display system using only passive elements. To solve this problem, a method for improvement of controllability using redundant brakes had been suggested. This method made it possible to display various force directions and various postures of virtual objects. However, the system with redundant brakes has the problem that it often become huge system. In this paper, we develop the new system which can display the opposite resistance force against handle on the arbitrary link posture. This system use only two ER fluid brakes for force generation, so become compact. Moreover, we perform basic experiment in order to verify this system.

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This paper proposes a new jumping unit that using chemical energy. Conventional jumping robots have difficulties to equip both lightweight and high output energy at the same time. In regard to this, chemical energy of black powder was adopted. Using explosives allows jumping robots to get high energy instantaneously. First of all, acceleration and velocity characteristics of the cylinder were clarified by experimental cylinder. The approximate expression of pressure change in the cylinder was derived based on the characteristics. Second, expressions of jumping theory were lead and relationships between some parameters (mass, rod-area, cylinder stroke) and jumping height were simulated. Curves with a peak were given from all of those parameters and existence of optimal value was clarified. The significance of the simulation was shown by jumping motion of about 2000mm by the experiment. Finally, four-legged robot dummy with jumping unit that change direction, control of height and isolated ignition were available, is developed. Trajectory of jumping motion was examined when the direction of cylinder was changed from vertical condition. Effectiveness of proposed method was confirmed from jumping height of 720mm with cylinder angle of 10 degree.

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The paper deals with the problem of automatic cleaning of glass windows. A small-sized glass cleaning robot has been proposed by authors. The robot is composed of two units sandwiching the glass by magnetic force. To improve the functional performance of the robot and increase the cleaning reliability, a sensor detecting the level of the glass dirt is introduced. The sensor is composed of light emitting and receiving sections. It detects the dirt by measuring the amount of reflected light which increases in dirty parts and decreases in clean parts of the glass. A signal processing scheme for this sensor is presented, and a motion control method incorporating the dirt sensor measurements is constructed. The validity of the control method and the feasibility of reliable cleaning are tested under experiments.

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This paper presents a laser based pedestrian tracking by multi-mobile robots in vicinity. Each robot finds moving people (pedestrians) from its own laser scan image based on an occupancy-grid-based method, and it tracks the detected pedestrians via Kalman filtering and Global-nearest-neighbor-based data association. The tracking data are broadcasted to multi-robots through intercommunication, and they are blended based on Covariance Intersection. By our tracking method, all the robots share the data of tracked pedestrians with each other, so that they can always recognize the pedestrians that are invisible to any robots. The simulation and experimental results validate the proposed method.

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Robot motions are designed according to mechanical structures such as frame structure, number of joints and so on. Therefore, structure changes such as joint failures or frame distortion make the designed motions unaccomplished. In service robots working for general users, it is desired to recover the motions autonomously. In trajectory controls, it is desired to realize motions with some trajectories even on the changed robot structures. Conventionally, motion adaptation methods with inverse kinematics and identification of changed structures have been used to solve the problems. But, for multi-degree-of-freedom robots such as service robots, the methods are difficult to apply. New motion adaptation methods are proposed in this paper. In the methods, all motions are expressed as time series of joint angles, and corresponding joint angles are generated efficiently on changed structure based on exploration methods. Representing postures are sorted by the Vector Quantization from the series of designed joint angles. Corresponding joint angles are found by the Simulated Annealing only on the representing postures because of reduction of exploration costs. Adapted motions to realize the intended trajectories on the changed structures are estimated by the Kriging methods. In simulation, the adapted motions which achieve the intended trajectories are generated autonomously without identification. Its exploration costs are reduced about 1/7 comparing with full search method.

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In the 21st century, as it is important to produce products with high quality, hybrid properties, multi functions, low cost, Eco-friendly and so on, the most of manufacturers need several daring plans, unique ideas, new technologies. Therefore a software for creating new materials with hybrid properties desired from many designers was developed and evaluated. Young's modulus, density, coefficient of linear expansion, specific heat and thermal conductivity for several properties were calculated by the software. This software has two functions which are (1) the calculation of the properties regarding the new composite material, with the selection of components and their component ratio and (2) the calculation of the composite materials and their component ratio for achievement of the desired properties. The software was evaluated by the several experiments. It is concluded from the results that; (1) the proposed software could calculate Young's modulus, density, coefficient of linear expansion, specific heat and thermal conductivity for new material, (2) this software has two functions which are both for the calculation of properties of a new composite material and for the calculation of component materials and their component ratio for achievement of the desired properties, (3) accuracy of the calculations using the software is about 7%, (4) the software was very effective and useful for development of a new composite material with several hybrid properties.

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Radio knife is a common tool in surgery. However it has a severe issue that it strongly adheres to the human body frequently through the coagulation of blood and/or human tissues. In order to overcome this issue, we developed the new tip for the radio knife that has ability to reduce surface temperature by vibrating or cooling. It was conducted that the new tip was evaluated in the scratch test between the tips and coagulated blood on the radio knife tip. As a result, adhesion force for the vibrated tip decreased to 36% comparing to normal tip, and adhesion force for the cooled tip decreased to 17% comparing to normal tip. From the results of dropped blood on stainless steel at several heating temperature, adhesive force was low when the blood heated lower than 65°C, on the other hand, it was high when the blood heated higher than 80°C. To prevent the coagulation adheres on radio tip and to keep the ability of cutting, the temperature difference between radio knife tip surface and the vicinity is important.

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In order to bring the nano processing technology using SPM (scanning probe microscope) probes from R&D stage to practical use, it is indispensable to improve its throughput drastically. One way to achieve higher throughput is fabricating an array of multiple probes and using these probes simultaneously. In this case, deviation of electric contact characteristics among probe tips may disturb the optimal processing action. In this study, the authors are focusing on the relation between the contact resistance and the contact force of nanoscale probe tips. We used an AFM (atomic force microscope) which can apply a bias voltage to a substrate holder and measured the contact resistance between an AFM probe tip coated with a conductive film and a surface of conductive substrates. The substrate surface condition should resemble the practical use. Therefore, we employed a cleaning process feasible in the actual manufacturing environment. By investigating the effects of the several factors such as the surface condition of substrates, the tip radius of probes, the authors studied the quantitative deviation and dispersion of the actual contact characteristics from the traditional contact theory.

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In this paper, we evaluated the mechanical loss of the geared motor, which consists of an induction motor with a rated power of 90W and a two or three staged parallel gear reducer. The result shows that the total loss torque was composed of a constant amount of loss at no loading, or the torque independent part, and the frictional loss which was proportional to load torque. The loss at no loading, which is the internal loss of gear reducer part, greatly contributes to the total loss. It was confirmed that the loss torque hardly depends on the speed due to a trade off between an increase in loss with rotational speed and a decrease in viscosity of the base oil due to a temperature rise. While the gears were lubricated with lithium grease, churning loss was not observed since any excess grease was squeezed out from the region to be lubricated. Furthermore, grease lubrication had less loss at the tooth mesh region than oil lubrication, which provided more attachment on the tooth surface.

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Gear couplings are widely used as connecting elements that can allow axis displacements caused between two axes in compact size. The recent demands to gear couplings are as follows, they are increase in load capacity, increase in allowable shaft angle and reduction in vibration and noise. So far, many studies have been conducted on relations of shapes of tooth surfaces, axis displacements, number of tooth pairs in contact, etc. However, there is no research that has analyzed tooth contact of gear couplings using the shape of tooth surface actually finished by various kinds of tools. In this paper, a method for calculating the tooth clearance of the gear coupling using the shape of tooth surface interpolated from many section profiles by means of parabolic approximation is proposed. The method was applied the gear couplings the gears of which are manufactured in the different ways and have different profiles. As the results, a new tooth profile that brings good tooth contact for gear couplings was developed.

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All types of NC machine tool interpolation are fundamentally based on linear interpolation, using the minimum interpolation unit of the drive. However, linear interpolation causes issues when machining curved surfaces, such as the feedrate not reaching the command feedrate and fluctuations occurring unexpectedly. These are mainly due to the NC interpolation process, and feedrate limiters. In addition, linear interpolation also decreases machining accuracy through inner cornering errors which are caused by acceleration and deceleration. Finally, it also lowers surface quality, by causing tatami patterns during zigzag cutting, due to differences in the locations of acceleration and deceleration in the forward and backward paths. Thus, in order to solve such problems, a method of generating cutter location data with consideration to the machine tool control characteristics, which are the NC sampling time, the feedrate limiters, and acceleration and deceleration, is proposed. The effectiveness of the proposed method is confirmed by simulations and experiments. Compared with a commercial CAM system, the proposed method increases the feedrate, smoothes acceleration and deceleration, and reduces the cutting time by approximately 50%. The proposed method also improves the surface quality and eliminates tatami patterns.

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Generally, ball bar instruments are used for the calibration of 5 axis machining centers. Also, some evaluation techniques using the R-test and tracking interferometer have been proposed. As those measurement instruments are expensive, the test method of machining accuracy that doesn't need special instruments is useful for the users of machine tools. In this study, a test method of machining accuracy is proposed for 5 axis machining centers. The test method uses the checkered pattern milling proposed for conventional three axis machining centers. In the checkered pattern milling for 5 axis machining centers, the hollow grooves are machined with a ball end mill in one direction. After that, the finished surface of the workpiece is painted, and the hollow grooves in orthogonal direction are machined by the simultaneous three-axis control motions of one rotary axis and two linear axes. The influence of the eight geometric deviations inherent to the tilting rotary table type 5 axis machining center on the checkered pattern is investigated by a simulation. As a result, when the four deviations exist separately in the 5 axis machining center, the checkered pattern changes individually at the checked intersections. Also, a new test method that is based on the checkered pattern milling for 5 axis machining centers is proposed. The new test method can evaluate all eight deviations to distinguish difference in the checkered pattern.

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As the substrates of semiconductor devices, silicon wafers are required to be highly flat in order to increase the integration density and the productivity of devices. Especially edge roll off, which is generated in polishing process as the final stage of the wafer manufacturing, is strongly demanded to be diminished. While various countermeasures are proposed and used practically, they cannot meet the demand. In the previous study, to meet the demand, a double-layered polishing pad having thin soft upper layer and hard lower layer was developed and the pad achieved the high surface flatness near the edge. On the basis of finite element structural analysis of a polishing model, the double-layered polishing pad with softer upper layer was expected to be more effective in diminishing edge roll off and, however, it is difficult to estimate the hardness of thin soft layer in actual. In this study, the indentation method based on the theory of elasticity was introduced to estimate the modulus of the above-mentioned upper layer. Modulus measurements on the polishing pads and polishing experiments on silicon wafers confirmed that the softer the thin upper layer is, the flatter the obtained wafer edge shape is and the newly developed double-layered polishing pad with softer upper layer improved surface flatness near the edge.

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Relieving of pinion cutters with a hob to reduce a grinding stock in relief grinding is introduced. The profile of the hob was calculated through virtual conical hobbing (cutting of the hob by the pinion cutter with a required cutting edge). The hob was manufactured and used for conical hobbing of the pinion cutter. Obtained results are as follows. (1) Both tooth profiles of the pinion cutter conically hobbed with a standard hob are different. (2) Both pressure angles of the hob that can conically hob the pinion cutter with the exact cutting edges are different. In this case, the step is produced at the tooth top of the hob by the difference in level of the rake faces of the pinion cutter. (3) Both relief angles of the pinion cutter conically hobbed by the hob with the calculated profile are different a little. In this case, by changing the helix angle in conical hobbing, both relief angles are made equal. (4) The trial-made hob was designed and manufactured, and hobbing tests of the helical pinion cutter were conducted. As the results, the possibility was shown that a cut pinion-cutter that does not need relief grinding can be manufactured.

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The objective of this investigation is an invention of theory and technics on surface roughness≒0, roundness≒0, and cylindricity≒0 boring as small diameter and long length. In this paper it is analyzed that high precision boring can be achieved with combining the insensitive vibration cutting mechanism, microgroove selfcontrol mechanism on (40Hz＋30kHz) superposition superfinishing, the main spindle system with air bearing and the carriage system with the pneumatic floating system. These mechanisms which can reduce cutting resistance are especially effective for precision boring, because in this case the rigidity of the tool shank is very low. The concrete methods are as follows: In the first process, the work which is chucked on the main spindle with air bearing is machined as acting a continuously and systematically pulsating cutting force by the ultrasonic vibration cutting mechanism. In the following process, the work is finished by the newly developed (40Hz＋30kHz) superposition superfinishing device. After all, to actualize machining surface roughness of 0.1～0.5μmRz, roundness of 0.1～0.5μm, cylindricity of 0～0.5μm/60mm, is succeeded in work material of duralmin, brass, carbon steel, stainless steel, hardend steel (H_RC39, H_RC52) .It is found that the high precision boring can be realized by means of this new machining process and its lathe.

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In recent years, manufacturing industries are facing severe competition to achieve products with high quality and low price. It is important to establish a new approach of creating value-added products like objects of craftwork or applied arts, different from traditional way of achieving products with high quality and low price. Manufacturing such value-added products generally needs skill and experience of experts. Thus, the objective of the study is to develop a CAM system for a multi-tasking machine in order to create value-added products, while converting implicit knowledge of experts into a formal knowledge. This kind of manufacturing way is named “Dexterous machining". The study deals with the CAM system to create a complicated shape consisting of bended columns as "Dexterous machining”. The CAM system developed in the study can generate the tool path for rough cutting and finishing cutting in consideration of interference avoidance. The effectiveness of the CAM system is confirmed by demonstrating two kinds of bended columns by use of a multi-tasking machine.

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Some machining methods were used for making prototype of biodegradable stent made from poly lactic acid(PLA) film. Decrease of the tensile strength and fracture strain after machining was frequently observed. Therefore, in this paper, the tensile strengths of the films after machining were evaluated. The tensile strengths had maximum average value of 127.2MPa by the cutting plotter, and the minimum average value of 89.4MPa by the excimer laser. The machined surfaces were observed by scanning electron microscope. The machined surfaces by the cutting plotter and FHG -YAG laser were relative smooth. Those by the excimer laser and oxygen RIE, however, were rough. That by turret punch press was relative smooth and had flake-like burr. The surface roughness was related to the tensile strength, but not always related to fracture strain. It is supposed that surface irregularity caused the stress concentration and it reduced the tensile strength. On the other hand, it is supposed that the fracture strain was affected by the changes of property of surface and inner material, and they was caused by the shear deformation and the resolidification, crystallization and degradation induced by the processing heat.

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This paper shows positioning of vacuum interrupter's motor which is used in a vacuum chamber. First, we produce a gate valve for vacuum and evaluate its function. The trial manufacture is generally repeated. However, decrease of trial manufacture is carried out. In the positioning of the valve, PI-D control is utilized and an output of MR sensor is fed back. In measurement using MR sensor, positioning within one second is realized, while accuracy of positioning is low. Firstly, by using reinforcement of bearing stiffness with permanent magnet, it is shown that positioning fluctuation is controlled. Next, by compensating both command signal and a MR sensor output, repeatability of positioning is improved. Moreover, three-dimensional dynamic analysis of motor in vacuum interrupter is executed using magnetic analysis software “MagNet7”. Comparing experimental and simulated positioning results, two results are almost corresponded. Finally, sequential operation of the valve can be executed without mechanical contact under surroundings of both atmosphere and vacuum.

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