In this paper, we study the nonlinear resonance phenomena and bifurcation phenomena in 1 degree of freedom magnetically levitated system. From the results of theoretical and experimental analysis, we clarify that the shape of resonance curve becomes soft type and period doubling bifurcations occur at the major resonance point due to the effect of the nonlinearity of magnetic force. We also show that the super harmonic resonance occurs with the shape of soft spring type.

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This paper presents a non-linear control for a magnetic levitation system of a flexible object based on passivity of the system. There are many researches on a passivity-based controller for the flexible manipulators. In these researches, controllers are designed without approximating flexible links into finite order model by truncating higher order vibration modes and linearizing non-linear terms in a neighborhood of an equilibrium point. Such linear finite controllers do not cause spillover phenomena and make wide operating area. In this paper, the magnetic levitation system is divided into two subsystems : an electrical subsystem and a mechanical subsystem. The controller for each subsystem is designed independently based on passivity. The dynamics of the flexible object are fully addressed and the results are valid for large deviations from equilibrium. The obtained controller dose not need current feedback for the electrical subsystem and consists of position, velocity and deflection rate feedback for the mechanical subsystem. It ensures asymptotic stability of the position trajectory and suppression of the elastic vibration. To illustrate the validly of our controller, some experimentals are carried out.

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For high speed and long term rotor such as energy storage flywheel, eddy current in the laminated steel sheet causes rotating loss. In this paper a new type of magnetic bearing which is based on the hybrid type is proposed. The stator has the foot to smooth the flux distribution in the circumferencial direction. Hence the rotating loss is expected to be negligible. To confirm the operation of the proposed magnetic bearing a simple experimental setup was fabricated and tested. The results indicated good fundamental operation and low vibration level. The rotor could run up to 12, 600 rpm without any serious problem. The free-run test confirmed reduction of eddy current loss compared with the standard magnetic bearing.

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This paper describes the experimental and analytical study on the parallel orientation of pins by sinusoidal vibration. A pin with a point at one end and a small spherical head at the other on a horizontally vibrating table is oriented in the direction parallel to the vibration. As long as the vibration amplitude and its frequency are appropriate, reorientation phenomenon occurs. Analytical study shows that the orientation depends on the magnitude of the maximum vibration speed of the table, that is, amplitude times frequency. The sense of the orientation of a pin depends on the initial condition.

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Spatial behavior of a pipe conveying fluid is examined theoretically and experimentally under the condition that the pipe has an asymmetrical spring supported end. The planar motion, nonplanar motion and beating phenomena of the pipe vibration exist depending on the flow velocity and the perturbed parameter of the spring coefficient. Furthermore the experiments were conducted with the silicon rubber pipe conveying water. The spatial displacements of the pipe were measured by the image processing system, which was based on the images from two CCD cameras. The typical feature of the self-excited pipe vibration, as predicted by the theory, was confirmed qualitatively.

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Squeal and vibration characteristics of a VTR (video tape recorder) guide roller are investigted experimentally and a mechanism of squeal generation is considered. The results show that the squeal frequency (about 2-5 kHz) is the same as the guide roller vibration (whirl) frequency and it is 35-60 times larger than the guide roller rotational speed (50-110 rps) in most cases. The guide roller rotates and whirls in the tape running direction (a forward whirl) with a nearly circular vibration orbit. The whirl (squeal) frequency can be estimated from the assumption that the guide roller rotates and whirls around the fixed shaft without slip. These indicate that the squeal generates by means of a guide roller forward whirl due to a dry friction acting between the guide roller and shaft.

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This paper describes theoretical and experimental studies of the velocity characteristics of a paper transport mechanism that consists of a short rubber-layered roller and a steel roller. The deformation and strain of surface of the driving rubber roller are numerically calculated based on Boundary Element Method by using Green's function that has been derived in the polar coordinates under the in-plane stress assumption. The effects of the normal load F and the paper tension T on the strain of the rubber roller are calculated. The velocity ratio of the paper transport velocity to the tangential velocity of the rubber roller is derived from the strain of the rubber roller. In order to verify the numerical results, an experimental setup of a friction drive mechanism for an endless paper was prepared. The paper transport velocity and the tangential velocity of the rubber roller were measured by changing the operating conditions. It was shown that the theoretical result can predict precisely the effect of the normal load F, the paper tension T and the rubber thickness on the velocity ratio in the range of-0.1?T/F?0.2 when 69°Hs rubber roller is used.

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This paper is a theoretical study on the stability of ID (inner-diameter) sawblade cutting a crystal ingot. Both the reaction from the ingot and the negative air pressure between the blade and the ingot are considered and their effects are represented by a series of parallel translational springs. The solution is obtained by the method of multi-modal expansion, further by applying the Galerkin method to the governing equations of system. Numerical results are obtained for a blade cutting a 12-inch crystal ingot. Results obtained show that the lateral reaction from ingot can cause the flutter instability for the ID sawblade, while the in-plane reaction force from ingot and the negative air pressure make little effect on the dynamics of working sawblade. Further it is shown that there are no flutter or divergence instability regions in the neighborhood of the practical operation speed of ID sawblade cuting a 12-inch crystal ingot, which also leads to a conclusion that the instability of blade vibration does not affect the surface finish of the produced wafer.

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The numerical analysis method for predicting the disk squeal simply and accurately has been studied by using the Substructure Synthesis Method. First, some experiments are carried out in order to understand the brake squeal phenomenon. Second, the numerical analysis method based on the Substructure Synthesis Method is conducted. Finally, the analytical results are compared with the experimental ones. As a result, it is found that the brake squeal occurrs when the natural frequency dominated by the disk coincided with that dominated by the caliper with the increase of the friction coefficient, and the analytical method developed here is found to be useful for prediction of the brake squeal.

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This study presents experimental and analytical results of squeal vibration in the disk-pad-caliper system, which is modeled after an actual disk brake. The system consists of a disk clamped along an inner edge and a pad supported by a plate spring (caliper). The frequency of squeal becomes higher as the thickness of the plate spring becomes large, and as the thrust load grows large. The squeal vibration of the disk near the contact area between the disk and the pad has translational motion, and the squeal vibration of this pad-caliper has translational and rotational motion. The disk and the pad-caliper vibrate with the same amplitude and the same phase at a point in the contact area. Therefore we analyzed the disk-pad-caliper system as a pin-disk model, which combined the disk with the pad-caliper by the point.

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This paper deals with analysis of bending vibrations of orthotropic plates by use of analytic solutions. The governing equation of orthotropic plate vibration cannot be expressed briefly in the polar coordinates. Therefore the Bessel functions and the modified Bessel functions are not available. The solutions used in this paper are exponential functions that express plane waves traveling in every direction on the plates. This kind of solution can be obtained always in spite of existence of anisotropy. The collocation method is used to satisfy approximately boundary conditions. Natural frequencies are calculated by the method of bi-section. Stability of numerical process in which plane wave functions are used is rather less than that in which the Bessel function are used. Accordingly, it is necessary to select correct results. However, the method can be used to save time of calculating and of preparing.

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When plastic deformation occurs in the piping under extreme seismic excitation, large damping effect will cause with the energy dissipation by plastic deformation. In this study, the simplified analysis method to obtain maximum response displacement of elastic plastic response of piping was investigated. The vibration energy and the dissipation energy with plastic deformation of piping were obtained by FEM analysis. The equivalent damping ratio depending on the piping response was formulated from both energies. On the other hand, piping response depends on the damping ratio. Both of them depending on each other were calculated as a pair of the converged values on each excitation level. The maximum displacements of the elastic plastic response calculated by this method resulted in appropriate simulation results to compare with excitation tests.

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In this paper, the stability of the thin cylindrical shell subjected to an axial leakage flow is reported. We focus on the circumferential (ovaling) vibration of a shell in this study. Equations for a shell and a fluid are described by the Donnell's shell theory, and the Navier-Stokes equation respectively, and the coupled equations are derived. As a result, the added mass, added damping and added stiffness are calculated. The influence of the axial velocity on the unstable phenomena is clarified. The numerical simulations are shown as parameter studies.

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The contact force between pantograph and contact wire is an important factor to estimate the performance of current collection of electric railways. However, the frequency range of measuring the contact force by the conventional method is not sufficient for this purpose. To measure the contact force accurately, it is required to precisely evaluate the inertia force of panhead. However, large errors occur in the inertia force in the high frequency region when measured by the existing method. This paper proposes a new method to measure the contact force, which can evaluate the inertia force of panhead precisely even in high frequency region by using the measurements of acceleration at plural points on the panhead. The results of theoretical calculation and excitation test of a pantograph can show that this method is effective for accurate measurement.

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This study shows how a mover moves by wireless in the inside a small pipe. The method is wireless energy supply method which used ultrasonic wave. Ultrasonic wave is the flow of wave energy. By receiving this energy, when the energy is radiated by transmission in a small pipe of ultrasonic wave, a mover operates actuator. That is, it is the method which converts ultrasonic energy into the movement thrust and a mover moves. In this paper, a mover of the new structure which moves by wireless was made, and the movement experiment was carried out. As this result, a mover became possible to moving in the inside of a small pipe when ultrasonic wave was received. Next, the movement mechanism of the wireless mover of this study was considered through the experiment. And it solved the movement principle.

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An experimental method to analyze the damping characteristics of hydraulic components is proposed in this report. By using our 3-mirophones Method, the absorption coefficient, propagation constants and the characteristic impedance of the component in the liquid-filled piping systems were measured. Experiments were conducted on the thin-tubes in the side branch pipe. Moreover, by using these damping characteristics of the component, we analyzed the pressure pulsation of the total hydraulic system. From the results obtained, this method is useful to evaluate the pulsation characteristics of the hydraulic systems.

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This paper deals with motion and vibration control for a flexible tower-like transportation system, taking account of elevator to lift payloads vertically. Applying a lumped modeling method presented by Seto and LQI-based control system, two controllers are designed which achieves good performance. Meanwhile, it is also rerealed that uncontrollable vertical vibration modes affects on control performance.

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This paper deals with motion and vibration control for a flexible tower-like transportation system, taking account of uncontrollable vibration modes called drumming mode. When the transportation system is constructed symmetrically, these modes are appeared as uncontrollable ones. For controlling vibration of whole modes under consideration, a structural modification in the design stage is carried out. Applying a lumped modeling method presented by Seto and LQI-based control system, the controller is designed which achieves good performance for controlling motion and vibration in the flexible transportation system.

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Rotational FRFs have not been measured in experimental modal analysis even though the importance of rotational FRFs have been recognized recently. Consequently it is difficult to utilize the FRFs on the basis of vibration testing for the structure modification analysis. The authors have proposed an estimation of the auto FRFs in rotation of structures. In the method a T-shaped rigid block whose inertia properties were known was attached to the measurement point on the structure. The estimation of three-degree-of-freedom (3-DOF) FRFs (one DOF in rotation and two DOFs in translation) of the beam structure using the T-shaped rigid block was demonstrated. The effect of estimated rotational FRFs against the random noise of measured FRFs were evaluated as a Reliability Factor. In this paper the estimation method of the cross FRFs in rotation and the reliability of the estimated FRFs are presented. A new rigid block whose overview is the cross-shape is designed for measuring 6-DOF FRFs. The 6-DOF FRFs of the beam structure is estimated. The structure modification analysis of 3D-rahmen structure based on experimental data is carried out.

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This study proposes new control systems to improve running stability of micro scale electric vehicle by using electric motor. Electric motor has the following merits : fast response compared with both an engine and a hydro-mechanical actuator, easy controllability of torque and formulation of torque characteristic, small and high power. These merits make it more feasible to implement traction control system on electric vehicles than conventional vehicle powered by engines. In this paper, traction control system based on LQI control theory is proposed for electric vehicles. The controller is designed with the objective to follow the disired relative velocity between the wheel and the vehicle body, instead of slip ratio as the conventional method. Finally, the effectiveness of the proposed controller is verified by the computer simulation and experiment that uses small scale electric vehicle with in whell-motors.

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This paper presents a mathematical model and numerical analysis for multiaxle vehicles operating on level ground. Considering possible factors related to turning motion such as vehicle configuration and tire slip velocities, equations of motion were constructed to predict steerability and driving efficiency of vehicles. Turning radius, slip angle at the mass center, and each wheel velocity are obtained by numerically solving the equations with steering angles and average wheel velocity as numerical inputs. To elucidate the turning characteristics of multiaxle vehicles, the effect of fundamental parameters, vehicle speed, steering angles and type of driving system, are examined for a sample of multiaxle vehicles. Additionally, field tests using a full-scale vehicle were carried out to evaluate the basic turning characteristics on level ground.

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This paper describes positioning and swing-rotation coupling vibration suppression of a cargo container. The cargo container is modeled as a rectangular rigid body suspended by four ropes from the trolley, traveling to the target position. The motion of the cargo container is analyzed and controlled, using the trolley with feedback traveling and an inertia rotor mounted on the cargo container. Eccentric loading causes swing-rotation coupling vibration and the control results are presented with experiments and simulations.

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In this paper, we propose the method used is the linear optimal tracking control, based on the discrete quadratic evaluation function. A new design method is presented for the tracking control with compensation input. This proposed method uses two degrees of freedom control, on condition of the limited terminal step. The optimal tracking control is formulated, and we have proved that this technique theoretically includes a preview control. It is shown by means of simulation, that the proposed method decreases the performance index value more than the preview control under some conditions. Finally, these approaches are applied to a manipulator, and the efficiency is verified by the proposed methods.

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This paper describes hovering and horizontal guidance control with H_∞ controller and performance verification through flight experiments for the hobby-class small-scale unmanned helicopter. Simple system identification method was applied to acquire single-input/single-output models. Cross-validation results have shown that those models were reflected in the actual dynamics very well. Attitude control has been constructed by proportional-integral feedback loop with derivative feed-forward compensator for improvement of reference following performance. H_∞ control theory was applied for horizontal velocity control. Four closed-loop transfer functions were shaped according to the design specifications given in the frequency domain. Also, horizontal position control has been designed as proportional-derivative feedback. In the flight experiment, good performance of hovering and reference following has been shown through 15 m square point-to-point traveling guidance control, and this also showed high accuracy of the models.

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We propose the speed compensation type Neural Network (NN) controller for position control of Ultrasonic Motor (USM). The USM has dead-zone which rotor doesn't rotate or rotates very low speed when control input is small. It is because the USM uses frictional drive as driving principle. The fixed gain type PID controller cannot carry out precise position control by influence of dead-zone. This proposed control method uses the NN controller such that relation between control error and rotation speed become linear. To realize this relationship, we introduce the weighting factor so that control error correspons to rotation speed. If the wieghting factor is chosen appropriate value, this controller realizes very small overshoot and precise position control. The effectiveness of proposed design method is confirmed by experiments using the existent USM.

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A new pre-teaching method for reinforcement learning using Self-Organizing Map (SOM) is described. The purpose of our study is to increase the learning rate using small number of teaching data generated by a human expert. In our method, the SOM is used to generate initial teaching data for the reinforcement learning agent from a few teaching data. The reinforcement learning function of the agent is initialized by using the teaching data generated by the SOM so as to increase the probability of selecting the optimal actions estimated by the SOM. Because the agent can get high rewards from the start of reinforcement learning, it is expected to increase the learning rate. The results of two computer simulations, mobile robot navigation and pursuit game, showed that the learning rate increased although the human expert had showed only a few teaching data.

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Numerical calculation of silica glass deformation in optical fiber drawing from preform has been carried out to reveal the effects of drawing condition on drawing tension and neck-down profile. Effects of drawing condition on drawing tension in optical fiber drawing are important in designing and setting of manufacturing process, because transmission characteristics of fiber is dependent on drawing tension when it is manufactured. Drawing condition is considered to have any effect on neck-down profile in drawing furnace, but it is not well known. This report presents numerical result of drawing tension and neck-down profile. It also shows how the distribution of value in drawing direction changes by drawing condition. The parameters of drawing condition are preform diameter, drawing velocity, heater temperature and its length. The ranges of them are 0.025-0.1m, 10-25m/ s, 2400-2550 K and 0.05-0.2m, respectively.

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Most optical styluses composed of laser diode and objective lens are troubled with signal noise when being traversed over engineering surfaces. The main cause of that signal noise can be attributed to laser speckle included in the reflected light from the object surface. It has been strongly demanded to decrease the influence of such speckle noise on the displacement signal of those optical styluses. In this study, a novel optical measurement system was proposed for a new optical stylus that has the speckle noise removal function. By using the newly developed optical stylus, surface profiles with less high frequency components were obtained for two kinds of machined surfaces with different surface textures. Applicability of the developed optical stylus to the profile measurement of engineering surfaces was experimentally verified.

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In this paper, we propose a new structural health monitoring method to detect bolt loosening using characteristics of local mode vibration of a thin plate sensor clamped to main structures by a bolt and a nut with washers. This sensor consists of a thin plate and some piezoelectric elements. The thin plate has a hole in its center to let a bolt pass through. An appropriate number of piezoelectric elements, normally four, are bonded on the surface of the thin plate. It actively vibrates in a local mode, which is not coupled with main structure vibration, in detection process using piezoelectric elements as actuators and sensors. In local mode vibration, the bolt's fastening force determines the boundary condition of the sensor. Bolt loosening changes the boundary condition and natural frequencies of the sensor. However, main structure's characteristics don't affect sensor's characteristics. That is, our method is not affected by the boundary conditions, the loading conditions and the vibration characteristics of main structure.

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This paper gives the pouring flow rate control of a cylindrical ladle-type Automatic Pouring Robot (APR). In order to obtain the control input, Betterment Process, which is one of learning control method, is applied to the pouring process. Furthermore, the pouring process model from the tilting angular velocity of the cylindrical ladle to the pouring flow rate, and blso to the liquid level in a sprue cup are built. The effectiveness of the proposed control method and the proposed pouring process model are shown through simulations and experiments of liquid level control on the Automatic Pouring Robot.

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In this paper the position control of a hydraulic cylinder using hydraulic transfomer is studied. In press machines or lifting equipments using hydraulic cylinder, a hydraulic transformer is used as a control component instead of control valve and a component for recovering potential energy of load. The transformer is a combination of a variable displacement pump/motor and a fixed one. Multiple closed loop controller with displacement feedback of variable pump/motor, speed feedback and position feedback of cylinder are designed and inplemented. With these controllers the friction torque and the leakage of the transformer can be compensated for and sufficient accuracy of positioning is achieved.

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This paper presents a disturbance estimation methodology on a Hexapod-type parallel kinematic machine tool of the Stewart platform. The disturbance estimation by monitoring an armature current of servo motors has been commonly done on conventional serial mechanism feed drives. On a parallel mechanism feed drive, a disturbance observer must have a more complex structure with a precise model of the gravity effect on servo motor loads, which significantly varies depending on the position and the orientation of a spindle unit. The estimation performance of the proposed disturbance observer is validated through static load tests and cutting experiments.

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Attitude expression suitable for directing an axis of a spacecraft to a specified direction is discussed. An expression that features no singularity between attitude parameters and a direction cosine matrix is introduced. Both new and former expressions are summarized from a unified viewpoint and the kinematical relations are derived. Then, the application of the proposed expression to pointing control of a spacecraft and to utilization of gravity-gradient torque is investigated. In pointing control, the proposed expression provides simple PD-type control to stabilize an axis direction. In utilization of gravity-gradient torque, it derives a simple and exact attitude that achieves an arbitrary gravity-gradient torque. The validity of the expression is shown by numerical examples.

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In our previous work, we developed a compact 6-DOF haptic interface as a master device which achieved an effective manual teleoperation. The haptic interface contains a modified Delta parallelink positioning mechanism. Parallel mechanism is usually characterized by a high stiffness, however, it is reduced by elastic deformations of both part and bearings. Therefore, to design such a parallel mechanism, we should analyze a structural stiffness of a parallel mechanism, including elastic deformation of both parts and bearings. Then, we propose an simple analysis method of structural stiffness for a parallel mechanism using bearings. Our method is based on common ideas such as static elastic deformation. However, important things of our method is how to combine these ideas and how to get a value of a elasticity coefficient of a rotation axis in a bearing. Finally, we will apply ous stiffness analysis method to the modified Delta and evaluate the reliability of our method.

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Aiming at the reduction of therapist burden in rehabilitation exercises, the authors have developed a technology to make a robot manipulator to be an assistive worker in kinesitherapy rehabilitation exercises by physical therapists. As for the kinesitherapy exercises, there are an exercise to sustain and to increase the arm joint's mobile range, an exercise to strengthen the muscle power and muscle endurance, and an exercise to train the muscle coordination function. This paper described some key technologies for the robot-aided assistive system : (1) a method to implement the four kinds of kinesitherapy exercises, (2) methods to estimate physical parameters were explained. The effectiveness of these methods was clarified by the practical experiments with a patient manipulator and an able-bodied person.

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Recently, much research regarding time-frequency analysis using wavelet transformation, WT, has been focused on analyzing wavelets, AW's that are derived form a mathematical approach. In the analysis in this study, the measured signal is adopted as the AW. In a general way, this method is applicable to inquiry of noise in industrial instrument and analysis of sounds, vibrations and biological signals. In an application of the proposed system, the correlation between brain waves of healthy elderly people and of senile dementia sufferers is analyzed. Brain waves are complex and non-stationary signals. To apply this method to time-varying signals such as brain waves, a new concept of instantaneous correlation factor, ICF, is introduced. This method uses WT by employing the measured signal as the AW. In this study, we use brain waves as the AW. As a conclusion, it is proved that a dominant feature of the correlation can be estimated by the ICF. Time-varying correlation is effective in the analysis of brain waves and will be useful in the diagnosis of senile dementia.

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We propose a method to evolve designs based on a user's personal preferences. The method works through an interaction between the user and a computer system. The objective of the method is to help a customer set design parameters by simple evaluation of displayed samples. An important feature of this method is that the design attributes which a user pays more attention (favored features) are estimated with Reduct in Rough Sets Theory and are reflected while refining the design. New design candidates are generated by the user's evaluation of design samples generated at random. While values of attributes estimated as favored features are fixed in the refined samples, the others are generated at random. This interaction continues until the samples converge to a satisfactory design. Thus, a personal and subjective feature is evaluated by this efficient design process. This method is applied to design a 3 D cylinder model such as a cup or a vase. This method is then compared with an Interactive GA.

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In this paper we deal with a two-machine robotic unit of flowshop type, in which each of n jobs is processed on the first machine and later on the second machine. Transportation of the jobs in this flowshop is performed by robots. There is an intermediate station with its capacity bound Q (1?Q?∞) between the two machines for intermediate operations such as washing, chip disposal, cooling, drying and/or quenching. The bounded intermediate station can process at most Q jobs at a time. The permutaion scheduling problem of minimizing the makespan (i.e., the maximum completion time of all jobs) is NP-hard for any fixed Q, although it has been known that the problem can be solved in O (n²) time if the intermediate station is unbounded (i.e., Q=∞). In this paper, we propose a heuristic algorithm for the problem with the bounded intermediate station. The performance of the proposed heuristic is examined by means of numerical experiments, and the results are reported.

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Many studies have been done to optimize the Kanban system as production control system. However, most of them can be effective on only limited conditions. Therefore, these studies have difficulties to be applied in practice. The purpose of this study is to propose the practical method to operate Multi-types and Multi-stages Kanban system using discrete event simulation. The method sets the number of Kanbans much larger than the estimated number on the simulation model. From the simulation result, the surplus inventory is found. By subtracting the surplus inventory from the maximum inventory, the necessary number of Kanbans and the average of inventory are determined. Also the changeover time is calculated from the simulation result. The performance of Kanban system can be measured through the average of inventory and the changeover time. The best plan to operate Kanban system is selected among many alternatives based on that performance. To confirm the effectiveness of the method, an actual test case is tried out.

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In the conventional end-milling research, operation planning is fragmented into partial planning such as determination of fixturing method, tool path generation and selection of cutting condition. Fragmented plans in operation planning are generated separately, although those generations are dependent each other. Advanced machining operations are directed to complicated and/or thin shape workpiece precision machining. This trend requires considering the interdependency among the partial plans. This paper presents a besic framework and procedure of coordinative generation of total operation planning. A distributed constraint satisfaction based schema is introduced in order to manage the interdependency among partial plans. A prototype system of coordinative generation is evaluated by a low-rigidity workpiece machining problem as an example problem. The results of example shows an effectiveness of the method.

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The use of ultra-violet curable resins as bonding agent can greatly reduce production cost by shortening the curing time from hours to minutes and by reducing air polluting fumes compared with thermosetting resins. Dicing blades with ultra-violet curable resins have been developed to enhance such advantages. A new conceptional blade has been proposed and developed, which is called a three-layered dicing blade. It has the structure composed of an inner layer with coarse abrasives for cutting and an outer layer with fine abrasives for finishing up at the same time. And in order to optimize uneven wear between the inner-and-outer layers of the blades, concentration of diamond abrasives in outer layer was increased and some kinds of fibers were mixed with resin as filler. As a result of the cutting experiments, in comparison with thermosetting resin blade and other single-layered ultra-violet curable resin blades, cutting performances have been improved.

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This paper reports about cutting load characteristic and deformation behavior of coated paperboard during indentation of a trapezoidal center bevel cutter. The cutter indentation was simulated numerically by using elastic finite element analysis in the initial compression stage without any cracks or fractures. By investigating the uniform compressive testing of paperboard in the thickness direction, the equivalent orthotropic moduli, included the strain dependency, were derived experimentally and applied to the numerical analysis model. Through this analysis, it has been revealed that the magnitude of the first peak load, being caused by the surface layer breaking of paperboard, is related remarkably to In-plane mechanical properties such as the tensile strength in the surface layer. On the contrary, it has been found that the equivalent moduli of the thickness direction characterizes primarily the cutter load response in the initial compression stage.

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The effects of cutting atmosphere and the repetition of intermittent contact-uncontact of tool-chip interface on cutting force and chip formation were examined on the case of 50 Hz vibration cutting. To confirm which matter in the air degrades the friction between the rake face of tool and the chip, some vibration cutting have been conducted under the atmosphere with inert nitrogen gas and the air. The resultant data shows that under nitrogen atmosphere, decrease of the friction was observed only the case on the vibration cutting in the air. On the other hand, there were no change on the conventional cutting and the vibration cutting in the nitrogen gas. This means some lubricative layer is made in the intermittent contact and uncontact between tool and the chip. Chip formation process in vibration cutting was also analyzed by Finite Element Method. In the intermittent situation in vibration cutting, loading and unloading are repeated. But no significant difference in chip formation can be observed, the change of frictional state has larger effect to chip forming process.

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An electroforming technique that enables the fabrication of grinding tools with fine diamond grains and high grain density was developed. A plating rig was employed in which a cylindrical cathode connected to a stepping motor was covered by an acrylic jig with a groove of 2 mm width and 15 mm length. In the case where a discontinuous rotation technique was employed, electroforming was conducted simultaneously with the sedimentation of abrasive grains by stopping the cathode rotation when the groove rotated to the top position. In addition, sedimentation and electroforming were conducted under the rotational vibration of the cathode when the discontinuous rotation technique supported by rotational vibration was employed. The grain density of the coatings was successfully increased to 45 Vol% when the discontinuous rotation technique supported by rotational vibration was employed.

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An attempt to develop a high-speed electroforming technique that can produce fine nickel/phosphorous alloy at high speed was made, in order to fabricate a microgrinding tool with superior bending strength. The amount of phosphorous acid dissolved in the plating solution was increased in order to decrease the deposited Ni/P grain size. The amount of nickel hydroxide that is commonly used for adjusting the pH of the plating solution to a fixed value was used to increase the current efficiency for high-speed electroforming. In addition, citric acid was employed as a pH buffer agent to prevent plating burn when the amount of nickel oxide increased. The current efficiency was successfully increased from 5 to 60% by using a citric bath where the pH of the plating solution was increased by the addition of nickel hydroxide. In addition, it was verified through the bending test that an electroformed coating with a deposited Ni/P grain size of 20 Å pocessed the same bending strength as the cemented carbide that is commonly used for the cutting tool.

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A method for predicting gear noise produced by a gear system was developed. This method calculates the distribution of sound pressure around the gearbox and identifies the areas from which noise radiates intensely. According to the sound-power level calculated from this pressure distribution, a low-noise gearbox was designed by adding ribs. The appropriate adding points were then calculated from the viewpoint of mass variation. It was found that to decrease the noise, ribs should be added in two places : (i) along the line with maximum curvature through the antinode of the gearbox's vibration mode or (ii) the minimum-length line which crosses the most contour lines through the maximum point of the sound-pressure contour map. It was also found that in the case of a gearbox with a vibration mode in which the gearbox side faces vibrate in opposite directions, noise can be effectively reduced by connecting the ribs on both side faces.

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Swing pad journal bearings consist of several segmented pads supported by curved laminates of rubber and metal. The pads swing and tilt because of the radial and circumferential deformation of rubber layer due to the hydrodynamic pressure in the oil film and also the frictional force. This type of bearing is expected to form a superior converging wedge in the oil film if the suitable values of design parameters is properly selected. Therefore, in the design of swing pad joural bearing, many parameters must be considered. The present paper evaluates such design papameters as the preload factor, the number of pad and pad configuration in simplified swing pad journal bearing whose pads are supported by a single layer of rubber. As the results, the swing pad bearing with lower preload factor and fewer number of pads is found to have superior performances. Furthermore, pad configuration and bearing temperature is found to affect the static characteristics in swing pad journal bearing.

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To clarify the dry friction and wear characteristics of spheroidal graphite cast iron under high sliding speed and high contact pressure, especially those in the state of thermal wear, the wear tests of sliding a cast iron pin on a mild steel disk were carried out by using the pin-on-disk type test rig. The variations of the friction force, the wear rate and the temperature rise with the sliding distance were experimentally measured and the relations among them were clarified. The friction and wear of spheroidal graphite cast iron pin are strongly influenced with the friction-induced tempera ture rise. Its wear rate changes in three steps as the increment of sliding distance because of the changes of its hardness by temperature rise (the first, the second and the third wear regions in order). The thermal conductivity and the hardness change by temperature rise of spheroidal graphite cast iron give the effects on thses three step changes of wear. Meanwhile, the coefficient of friction decreases in the first and the second wear regions as the sliding distance increases, and it finally converges to some constant value in the third wear region. From the experimental results, some empirical formulae giving the relations between the coefficient of friction and the wear rate versus the sliding conditions were derived.

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