The authors present a new step-by-step integration scheme by utilizing the cardinal B-splines. The new method organizes conventional implicit methods such as Newmark-β method and Wilson-θ method and so on, and provides a simple computation procedure so that the step-by-step integration can be carried out efficiently. In addition, when we analyze a nonlinear system with discontinuity the computational acuuracy can be improved by the approximate detection of the points of discontinuity by making good use of the two-scale relation. In this paper, we formulate an algorithm of a time historical response analysis of a straight-line beam structure as an elementary example of multi-degree of freedom system besides a simple single degree of freedom system. The cardinal B-splines used here are only the ones of orders 3 and 4 but the other cardinal B-splines are also available for step-by-step integration in the same way.

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The collocation method using analytical solutions has an important inherent issue that causes the loss of the eigen value convergence due to singular points existing in the vicinity of a domain. In our previous study, we proposed a way to cancel it in a specific domain including a notch by adding singular terms to the general solutions. This method, however, can not easily be extended to general singular problems. To overcome this fault, we present a newly improved method that employs a domain decomposition approach in order to relax the effects of any singular points. First, the conditions for continuity between two decomposed domains are derived. Second, the eigen value equations are formulated based on these condition. Finally, using some examples, it is confirmed that the method presented here provides a high acuuracy of eigen values in any problems accompanied by singular points.

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We propose an efficient method for calculating damping characteristics of 3-dimensional 2-layer damped structure containing viscoelastic materials to save computation time, by using single layer finite element model for only metal structure and normalized strain energy of out-of-plane and in-plane deformation. In this proposed method, iterative calculation of eigenvalue analysis in full size matrix can be neglected and matrix size of the eigenvalue analysis is smaller than taht of the conventional modal strain energy method which uses 2-layer finite element model. Also, when thickness or location of the added viscoelastic materials is changed, we do not have to carry out eigenvalue analysis again. Furthermore, from the calculated results of normalized strain energy, we can estimate approximate tendency of effect of viscoelastic materials on damping characteristics of the 3-dimensional structure. This proposed method is applied to simple 3-dimensional 2-layer damped structure and calculation results are compared with experimental data and calculated results by using complex eigenvalue analysis and conventional modal strain energy method. Calculated results by the proposed method agree considerably well concerning loss factor and natural frequency.

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A smart structure using piezoelectric devices electrically shunted by an inductor-resistor circuit was tested for passive microvibration control of an aluminum beam of a 1010×60×30^Tmm size simply supported at both ends. The piezoelectric devices were attached to the beam on the top and bottom surfaces at the middle point of it. It is known that such devices with a shunted circuit work like a dynamic vibration absorber. For the piezoelectric devices, 8d₃₃ stack type devices of a 10×10×20^Hmm size, and 2d₃₁ type devices of a 60×60×5^T mm size were tested, showing almost the same performance. Through the tests, it was confirmed that the smart structure could effectively suppress microvibration of the beam in a high frequency, and the smart structure could be applied to microvibration control of precision equipment.

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This paper investigates the structure of three types of free giant swing motions for a 2-dof link mechanism that were derived by both an optimum trajectory planning method and a forward dynamics analysis. Based on the modal analysis to the linearized dynamic equation of motion, we showed that three giant swing motions under zero gravity force are the rigid mode rotation, positive and negative superposition of the vibration mode on it. Since the frequency of the vibration mode decrease with increase in the amplitude of the vibration mode, free giant swing motions are realized at the amplitude at which two modes synchronize. There can exist odd number of periodic motions more than three depending on link parameters. The motion shapes are deformed by gravitational force, and two types of giant swing motions collapse as the motion period increases.

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This paper deals with the problem of quenching chatter vibrations of an automotive wiper. As a means for quenching chatter vibrations, we consider application of harmonic excitation normal to the sliding surface. To study whether the harmonic excitation is effective, first we study by numerical simulation and by experiments the friction characteristics between the wiper and the glass surface. We find that the harmonic excitation decreases negative slope in the friction characteristics. Then we study by numerical simulation and by experiments, effects of the harmonic excitaion on the vibrations. We find that, if the amplitude of the harmonic excitation is of the same order as the magnetitude of the static normal load, the harmonic excitation quenches the chatter vibrations. We also find that, for chatter vibrations of subcritical type, it is enough to apply the excitation for a short period till the vibration is entrained into an equilibrium state.

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Because of the current air pollution problems in large cities, it is hoped that low emission vehicles such as electric vehicles or hybrid vehicles can be popularized. There are two main types of hybrid vehicles, series and parallel. The series type is basically an electric vehicle which uses an internal combustion engine to charge the battery for the electric motor. By using both a gas-powered engine and an electric motor is increased substantially to the point where comparatively little gasoline is required to run the gas-powered engine. The paralles type vehicle is different from the series type in that it uses the gas-powered engine as well as the electric motor to drive the vehicle. In this case it is important to effectively use both the electric motor and gas-powered engine to drive the vehicle. In this research a model matching control is used to effectively control both the traction forces. The effect of using this controller on the engine running performance and effectiveness are studied.

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This paper deals with the pre- and post-impact motion of vehicles. In general, vehicles incline their chassis due to the variation of wheel loads during motion. The authors have already suggested the analytical method for the motion of four-wheel vehicles in which the wheel loads were solved as unknown values. However, the inclination of chassis was not considered in the previous paper. When the chassis is inclined, the moments about the vehicle center of gravity vary because the projective distances between the center of gravity and the wheel contact points to road surface change. Therefore, we take the inclination of chassis into consideration in this paper. Since the equations of motion of the vehicle become nonlinear with respect to the wheel loads, they are solved iteratively under influence of inclination of chassis at each time step of calculation.

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This article presents a new levitation technique, which uses a small superconductor and a set of permanent magnets. In the system, a small superconductor is connected to the bottom of the vertical shaft. The gravity force and axial vibration force are supported by the superconductor. A circular permanent magnet is attched to the top of the shaft, and the other circular permanent magnet lies at the frame. The N-pole of one of the magnets faces to the S-pole of the other magnet, so a drag force acts between the magnets. The drag force is unstable in the axial direction, but the pinning force in the axial direction of the superconductor makes it stable. There is a restoring force in the horizontal direction between two permanent magnets, and in addition, there is a pinning force of the superconductor, so that both ends of the shaft are stable in the horizontal direction. This implies that the levitated shaft is stable without control. In general, controls have to be made in either axial or horizontal direction when the ordinary magnets are used. The levitation technique presented in this paper has advantages, Because, in order to have stable levitation, only one small superconductor is required, and a cooling system is simple. A method for passing through the critical speeds is also presented. In the method, rotating conductor disc is used to have the electromagnetic damping. Both the analysis and experiment are presented.

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This research deals with theoretical evaluation of electromagnetic force and torque acting on a permanent magnet (PM)above a high-T_C superconductor(HTSC). While, as one potential application of HTSC magnetic levitation, HTSC bearings for energy storage flywheels are expected, it has not yet been theoretically clear whether HTSC levitation can work as an efficient bearing. In this research, force and torque acting on a PM above a HTSC were evaluated by the advanced mirror image method, which is based on the fact that magnetic flux at the field-cooling is trapped in type-II superconductors. Numerical results based on the above method showed good agreements with experimental ones. For a magnetic dipole over a flat ideal HTSC, the exact analytical solution of the force and torque was obtained as functions of the displacement and the Euler angle. This solution shows that the force and torque acting on the PM are theoretically equivalent to ones acting on a rigid body supported by an overhung elastic shaft, and gives the magnetic flexural rigidity of the HTSC levitation.

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A new optimum design method of flexible rotor shaft configuration using closed loop system redesign is proposed. The rotor system is supported by active magnetic bearings(AMB). The proposed method is constructed from two steps. First, unbalance resonance vibration control loop of AMB is designed for a rotor, that has intial configration, to realize the specified closed loop pole assignment. The pole assignment is specified by the user in advance. And then, the rotor shaft configuration is iteratively modified to minimize the objective function under the closed loop pole assignment constraint. Objective function is defined as a linear conbination of the measures of optimality of the control system design such as the control energy consumption of unbalance resonance vibration control, the magnitude of critical resonant of the rotor system. A ccording to the redesign method, closed loop pole assignment is not changed in each iteration of optimization process. It means that the critical speeds of the rotor system and the corresponding Q-factor of each critical speed before and after optimization remain unchanged. The effect of the proposed method will be shown by the numerical simulation results of the flexible rotor design example. Not only the rotor shaft configuration but also the control gains of AMB are successfully optimized by using the proposed method.

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One of the most important functions of a cargo handing machine such as a transfer crane is sufficient cooperative operation with a container crane at a port container terminal. To minimize the container handling time, i.e.consolidate the convergence time of sway motion, a low-pass filter is used to separate a rocking vibration component from sway detection signal in a conventional control system. However, the characteristics of the low-pass filter produce a phase delay of the sway detection signal, which lowers anti-sway performance. In order to improve the performance, a notch filter with on-line system identification of rocking frequency is used instead of a low-pass filter as a filter for removing rocking vibration. Result of numerical simulations show that the proposed method decreases the convergence time for a sway of 200mm to 50mm from 10.9s to 6, 2s.

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Semi-active on-off damper can achieve a good performance close to that of an active control damper with much lower cost and complexity. However, the acceleration response of an on-off damper exhibits discontinuities at the time of switching, thus a significant jerk may be experienced by the system mass. In this study, based on analysis of present semi-active on-off damper, two types of new "on-off" dampers with the variable damping coefficient, which can improve significantly discontinuties at the time of switching, were developed. The time rate of change of damping force and jerk on mass(the time rate of change of acceleration)were investigated and used to evaluate the smooth degree of the damping force and the acceleration. The vibration performance was compared with that of conventional semi-active system. The result shows that the new types of on-off dampers can improved the vibration performance in the high frequency ranges.

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Aerodynamic stability is one of the most important themes in the design of super long-span bridges, and various methods for stabilization have been investigated. This paper deals with the effect of a tuned pendulum damper(TPD)on bridge deck flutter, and describes an analytical and experimental studies on the effectiveness of TPD in suppressing the wind-induced coupled flutter of a bridge deck. The flutter analysis and a wind tunnel test for a two-dimensional bridge deck model was performed. The flutter speed was increased by 20∼30% by TPD with 5% mass. Moreover, the mechanism of flutter suppression by TPD has been investigated by Bode's diagram. It was cleared that the mechanism of that was due to the decreasing the response of the deck torsional mode and the changing the phase of a flutter system.

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We propose a new regular position stopper mechanism of the running wagons being capable of the wide application about the weighty matter storing system. It is composed from the magnetic brake and the spring system installed on the wagon. The wagon decelerates in the preselected speed level by the magnetic brake. The brake mechanism installed in the wagon collides against the stopper and comes to a stop at the regular position suppressing the shock by the action of the spring system. It gives the distinction that the wagon is without using the feed-back control system and makes the rapid stopping action. About making up the 1.5ton wagon running test equipment, we made a clear for the fundamental design methods, analyzing the action modes, and stopping about the error 1mm.

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A new magnetic force control method using a giant magnetostrictive material(GMM)is proposed. Magnetization of GMM varies with applied stress. In magnetic circuit composed of a permanent magnet and magnetic yokes, the change of magnetization can be transduced into magnetic force variation. The feasibility of this method is examined by a simple experiment. For the purpose of estimating the force variation, the magnetic circuit is analyzed by finite element method on the assumption that the magnetization variation is equivalent to relative permeability change. This magnetic force control method is expected to be applicable to magnetic actuators and has advantages such as high response, low heat generation and high energy conversion efficiency inherent in the characteristics of GMM.

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For a large number of engineering problem, we may encounter hysteretic damped systems. Internal damping in the viscoelastic materials and structural damping at a joint, support, bearing, or other assembly are considered to be the hysteretic damping. The principal difference between the viscous damping and the hysteretic damping is that for the viscous damping the energy dissipated per cycle depends linearly on the frequency of vibration, whereas for the hysteretic damping it is independent of the frequency. In this paper, we derive the exact algebraic solutions for design of a hysteretic damped dynamic vibration absorber attached to undamped or damped primary systems for various performance indexes. The absorber is designed on the basis of the H_∞ optimization, that is, minimization of the maximum amplitude response of the primary systems to periodic excitation. The solutions obtained here are compared with the approximate ones based on the classical method familiarly called the fixed-points theory.

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A wide range servo system for a magnetic head actuator was studied while considering the inphase property. The in-phase property can be defined for a structure system whose transfer function is described as a summation of a rigid-body mode component and flexible mode components. When impulse response of every flexible mode takes the initial derivative of the same sign as the rigid-body mode, the system is in-phase. It is demonstrated that the in-phase property brings much higher controlperformance than out-of-phase one. We examined feasibilities for a wide frequency range surpassing over resonance mode for an in-phase structure system of a magnetic head actuator. We also proposed a methodology for designing in-phase structures.

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For servo systems with unknown reference inputs, this paper proposes an adaptive servo control system identifying the unknown reference signal model. The controller is for a discrete-time, single-input single-output plant. According to the internal model principle of servo control systems, it is neccessary to include the model of a reference input in the servo controller. The servo controller proposed in this paper includes a model identified on-line as the internal model. The design is based on coprime factrization of the plant model over the ring of stable rational functions. It is proved that all internal signals in the control system, error equations and parameter identification law are uniformaly bounded. The scheme is applied to the cart position control of a double inverted pendulum control system.

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In assembling parts, we sometimes have to use large deformation of flexible parts. Buckling deformation of beam has been analyzed mainly for the strength of beam that supports large longitudinal load, but not for the large deflection. We know a rare research for assembling a beam into a hole in a specially deformed beam case, where the beam has small longitudinal load and the deflecting end(DE)lies on the tangent of fixed end of the beam(TFEB). This paper deals with large load acting at the DE and large deformation where the position of DE offsets itself largely from the TFEB and sets itself on shortened position along the TFEB compared with the beam length. Jumping position from a type of beam deformation to another type and the DE traces of those types are clarified and checked experimentally.

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In this paper, we consider a model referecne control for a plant which has both unknown static friction and unknown plant parameters. An adaptive controller estimating the unknown friction and parameters is proposed. This controller guarantees global asymptotical stability of output error between plant and reference model outputs. Extending the controller, we also construct a robust controller for L₂ disturbances. Finally, we have applied these controllers to a pneumatic valve. Experimental and computer simulation results show the effectiveness of the controllers.

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This paper explains an optimum design concept for a designer's intentions in controller design. We consider multi-objective optimization through the Nash bargaining model ; an optimum solution attainable from Nash's study. We then optimize a feedback gain of LQR(Linear Quadric Regulator)on a motor-mass system to show the concept's effectiveness. In achieving the LQR optimization, we aim to simultaneously reduce output errors and input amplitude. Based on the Nash bargaining model, the criterions, output errors and input amplitude, are represented by numeric values, called utilities, which formulate a compromise point. Afterwards, a design solution is evaluated from this point. The resultant solution satisfies a designer's intention.

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The purpose of this study is the improvement of the efficiency of design process that reaches to detail design from initial design. Genetic algorithm is applied to the initial design stage and conjugate gradient method is applied to the detail design stage. The design solution obtained by GA can be adopted as an initial design solution in the detail design stage because GA has the advantage of the capability of the global search in the optimization process. Furthermore, the regularization method is applied as an avoidance strategy of the ill-posedness that encounters at the process of the detail shape determination. The effectiveness of the proposed method is examined through an application to the optimization problem of the inner boundary shape determination in temperature field.

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Amusement robots and entertainment robots must have actions with fertile emosions. New systematic methods to design their actions are desired. For this reason, the authors analyze the actions of a Bunraku puppet. Bunraku is a classical puppet show in Japan and typical emotional actions are expressed by experts of puppet manipulation. The actions of a Bunraku puppet which is manipulated by the experts are observed and analysed. The emotional factor of the actions are extracted and the authors propose a method to design actions by emphasizing these extracted emotional factors.

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In order to establish method to design humanoid robots' motions with fertile emotions, the authors are analysing the Bunraku puppet's motions which are generated by the experts of puppet's manupulation. The many puppet's motions with some functions and with some emotions are observed. To simplify the observed puppet's motions, each puppet's motions are divided into the motion of the puppet's axes(the main part of the motion)and the relative motion(accompaniment). In this paper, the motions of the puppet's axes are analysed. The graphs of the motions of the puppet's axes consist of same factors if the motions have the same functions even though they have the different emotions. The graphs of the same factors have similar forms, but their time length and amplitudes differ, if they have the different emotions. The above factors are computed from the data of the motions of the axes based on the wavelet coefficients of the data which express the local forms of the graphs. The authors analyse how the time length and the amplitude of the factor changes as its emotion changes. This knowledge is applied to generate humanoid robots' motions with fertile emotions from their motions with no emotion.

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We develop a new method of trajecory optimization of redundant flexible manipulators for collision-free utilizing the B-spline function and a mathematical programming method. We adopt an approximate flexible manipulator model which consists of rigid bar elements and spring elements. We use B-spline function for determining the approximate trajectory and the expressions of the outline of obstacles. The used total performance index consists of 2 performance indices. The first is the driving energy, and the second is the trajectory deviation which is caused by the approximate modeling for the flexible manipulator. We design optimal collision-free trajectory of flexible manipulators by searching optimum position of the control points for B-spline approximation which minimize the performance index subject to constraint condition for collision-free. Some examinations through numerical examples show the effectiveness of the method.

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X-screw, a load-sensitive linear actuator that we have proposed, has many desirable characteristics, but one drawback is that the linear motion is much slower than a conventional lead screw. When the axial load is small, the transmission efficiency of X-screw is approximately the same as that of a lead screw since the transmitted power is low in this case. Therefore we have developed a Dual Mode version of X-screw called "DM X-screw". This mechanism is able to automatically switch between lead screw mode and X-screw mode in rewponse to the axial load. This feature makes it possible to apply DM X-screw to many mechanical system. We have used this mechanism in a pantograph jack that makes use of its dual mode load-sensitive variable transmission properties. This jack can be operated with a small imput force and unlike conventional jacks, several of these jacks can be used in combination to overcome the output force limitations of normal pantograph jacks.

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Tactile sensation of surface textures is an indispensable clue in a touch feel design task using a virtual environment or in a remote object manipualation task. In this paper, we discuss two methods to present multilevel tactile sensations followed by the introduction of a vibratory tactile display developed by the authors. The first method is to produce a pseudo-multilevel intensity on the basis of a binary dithering, which permits a reduced control load of the display. The exponent value of Stevens' power law was determined through an experiment. Regarding the second method employing direct amplitude control of display pins, the sensation intensity was scaled in terms of vibration amplitude based on a JND method. To evaluate the validity of the obtained scale, curves of intensity were presented on the scale. The result of the discrimination experiment exhibited a sufficiently high ratio of correct answer that suggested the availability of the scale for displaying multilevel textures.

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We aimed for permanently supplying the electrical energy to an apparatus for in vivo use such as a cardiac pacemaker and proposed a totally implantable electrostatic(ES)generator that harnesses the motion of a living body. ES generators need initial charge suplies(ICS). Since such a charge supply always consumes electrical energy while generating, we must take its life into account in case of a portable battery. The proposed generating system, which does not consume electrical energy of the ICS, consists of a battery as the ICS, a variable capacitor(VC)in which mechanical energy is converted to electrical energy, a capacitor for energy storage and two rectifiers. To verify validity of the system, a honeycomb-type variable capacitor whose capacitance varies from 70 to 210[nF]was used. It was possible to generate maximum electrical energy of approximately 34[μJ/cycle]in case of the ICS with constant voltage of 24[V]. We found that the ICS of the ES generator did not consume electrical energy in a cycle and its voltage should be chosen to be higher to generate higher electrical energy without lack of safety.

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We studied a magnetic recording head of a three-pad-slider which had flat-inclined air-bearing surfaces. We expected a small friction force and a small velocity dependence on the flying height from the configuration. We confirmed these expectations by manufacturing heads with MR elements. We also performed continuous 1000-hour seek tests and read/write tests and found that the variation of signal amplitude was less than ±20 percent. After the tests, there was no measurable wear for three heads at the front contact pads and the rear contact pads among the total four tested heads. There was no measurable wear on the disk surface as well. These results demonstrate the sufficient durability of the head-disk interface.

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Recently, spiral bevel gears have come to be used widely as transmission gears of cars Running test of gears was a most effective method for rotational vibration measuring of gears. However, the use of acceleration sensor equipped with gears for estimating of rotational vibration was not practical from the viewpoints of cost and production control. In this paper, we discussed a easy method measuring rotational acceleration of Oerlikon spiral bevel gears under various conditions, using acceleration sensor on the output shaft flange. It was shown that this method was effective to estimate behavior of spiral bevel gears under running condition. Additionally, the transfer function between the acceleratoin of the driven gear and that of flange were measured. It was clarified that applicable range of this method can be obtained by the transfer function under static condition.

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This paper presents a study on reduction of gear noise with active noise control(ANC). An ANC system of feed forward control type on the basis of the Filtered-X LMS algorithm was developed. As a basic study of the noise reduction with ANC, the ANC experiment using duct was carried out with recorded noises of SCM 415 case-hardened and ADI gears for the cases where the gear noise and the signal of sinusoidal waveform with mesh frequency were used as the reference signal in the ANC system. Furthermore, the noise reduction of ADI gears with ANC using an actual power-absorbing-type gear testing machine was examined for the case where the vibratoin acceleration signal of bearing box was used as the reference signal. It was shown that the present ANC system was useful for the reduction of gear noise. The frequency analyses of gear noises were carried out, and frequency components reduced with the ANC were determined.

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A new form relief grinding method for an involute pinion cutter with almost no regrinding error is proposed. In the method, the tooth flanks of pinion cutter are finished as those of involute helical gears with excessive(lager and smaller)helix angles than that of the pinion cutter. The obtained results are as follows : (1)In the conventional generating method, it is impossible to finish an involute pinion cutter with no profile error. (2)The profiles of grinding wheel to finish a pinion cutter under excessive helical motions are calculated. (3)Profile errors of a pinion cutter being finished by the proposed method are smaller than those finished by the conventional method. (4)The finishing test of pinion cutter(m_n=2.5mm, N=39, β=15°)was conducted on the NC form grinding machine and the pinion cutter with the accurate cutting edges was obtained.

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Sharpening of a hob with helical flutes is a difficult problem in the gear production field because interference between a grinding wheel and hob rake face is apt to occur. In this paper, mechanism of interference in hob sharpening is analyzed and the condition without interference that causes a trouble is shown by means of the figure. Then, the profile of grinding wheel for sharpening the hob with helical flutes is calculated using the element removal method in the same way as form grinding of the helical gear with a profile of straight line. Also, the relation between the depth of hob flute and the tooth height of hob rake face being finished is shown by means of the figure. The sharpening test of the involute worm hob(m_n=5, N=3, γ=23.917°)was conducted using the CNC gear form grinding machine. The radial alignment of hob rake face after sharpening was less than 5μm.

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The dynamics of speed ratio control system of a metal V-belt CVT depends upon the clamp force characteristics at a concerned speed ratio. The system is getting unstable in the region of maximum reduction ratio at no load where the speed ratio changes easily by a small change in clamp force ratio. This paper clarifies this phenomenon by making analyses on the steady state relation between the clamp force ratio and speed ratio on the basis of a friction drive theory, and on the linearized motion control. The parameter defined by the change in the clamp force ratio per unit change in the speed ratio varies the damping ratio of the system. Especially in the reduction ratio range the damping ratio becomes small, which explains the instability observed in the experiments.

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This paper describes a general methodology for the optimum design of magnetic head sliders, in which the objective function to be optimized is defined as weighted sum of the static and dynamic flying characteristics such as the minimum spacing, maximum difference in the spacing due to variation of the radial location of head, and maximum amplitude ratio of the slider motion, etc. As an example of optimum design, the optimum design variables of IBM 3380-type magnetic head slider are determined, and the results obtained are compared with the randomly selected design variables to confirm the effectiveness of optimum design. Moreover, the characteristics of optimum solutions are discussed by checking the variation of design variables with progress of optimization.

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This paper describes the optimum design methodology for remarkable improvement of the static and dynamic characteristics of hydrodynamic journal bearings and its application to elliptical journal bearing design used in high-speed rotating machinery. The hybrid optimization technique combining the direct search method and the successive quadratic programming(SQP)is applied effectively to find the optimum solutions. In the optimum design of elliptical journal bearings, the four design variables such as vertical and horizontal bearing clearances, bearing lenght-to-diameter ratio and bearing orientation angle are determined to minimize the objective function defined by the weighted sum of oil film temperature rise, leakage flow rate and the inversion of whirl onset speed of the journal under many constraints. The results obtained are shown in graphical form for a wide range of journal rotational speed. Comparing the optimized static and dynamic characteristics with the characteristics calculated from the random selected design variables, the effectiveness of optimum design is verified.

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A simple method was devised for predicting how much the crank pin journal temperature of a modified bearing specification would change in relation to the baseline specification. In this study, analyses were first conducted to determine the oil flow rate at the big-end bearing which is a major determinant of the crank pin journal temperature. A bearing oil flow rate analysis was conducted by using the bearing oil film thickness found by an elastohydrodynamic lubrication(EHL)analysis and the crank pin oil hole outlet pressure found by an oil hole pressure analysis, and the bearing oil flow rate was predicted. An analysis was then conducted to predict the crank pin journal temperature using the oil flow rate and friction loss found by the oil flow rate analysis and EHL analysis. That method was then used to examine the effect of each bearing specification on the amount of change in the crank pin journal temperature.

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This paper deals with the influence of concentration of Ca sulfonate on tool wear and finished surface roughness in hobbing. Experiments were carried out using a fly tool. The effect of concentration of Ca sulfonate with using(Al, Ti)N coated tool is greater than that with using TiN coated tool. With a(Al, Ti)N coated tool, the concentration of 10%∼15% of Ca sulfonate is suitable for obtaining longer tool life, which is superior to the chlorinated fatty acid ester. Though the crater wear trends to increase with an increase in concentration of Ca sulfonate, the finished surface roughness has a tendency to decrease. It was suggested that when the Ca sulfonate was used for coated tool, the Ca composition affects on the effect of coating film, resulting the extension of tool life. The use of Ca sulfonate is effective for environmental pollution control and for improving the safety of the operator.

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An abrasive jet is a water jet that contains abrasive grains, and has a greater processing force than that of a water jet. It is quite difficult to know how an abrasive moves in a high speed water jet, and the machining mechanism involved has not been revealed yet. In order for abrasive jets to be used effectively in a wide range of fields, their mechanism must be clarified. We analyzed the surfaces of workpieces processed by an abrasive jet and the forms of chips to know the machining mechanism involved. It was revealed that in the case of a water jet, the surfaces of workpieces deteriorated in both the upper and lower sections, while an abrasive jet produced good surfaces in the upper section, but its surfaces deteriorated as it moved down the workpiece. This is because the abrasive's speed is great enough in the upper section to grind the surface of the workpiece, but when it slows down as the machining proceeds through the workpiece, the abrasive loses its effect. It shows that in the lower section the erosion mechanism of an abrasive jet is the same as that of a water jet. It corresponds to the results obtained from the analysis of chip forms, too.

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It has been required that the packaging density of PWB(Printed Wiring Boad)is improved because high packaging density technology has allowed downsizing. Therefore, high-quality micromachinings are necessary for PWB. Especially, it is necessary that a great number of through-holes have to be drilled with high reliability to make a circuit. So it is required to improve the quality of the drilled hole. However, it is inevitabole that the quality of the drilled hole is varied owing to the wear of the cutting edge in a great number of drilling. In this paper, it is shown that the shape of the cutting edge is related to the damages around the drilled hole. And the internal damage, the surface roughness and the smear of the drilled hole are increased, as the number of drilled hole is increased. Additionally, it is cleared how the variation of edge shape due to diamond coating affects the drilled hole quality.

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Recentoly, as a product with complex form increase for multiple functions or high quality, a worker must machine and assemble some parts with high precision. Especially, if worker assemble the plural parts with high positional or high attitudinal deviations, long time and high cost are necessary. Therefpre, in this paper, a tightening system of bolt for assembling during plural machining was developed. This system consists of a tightening shank of bolt for assembling some parts and a bolt stocker for supplying some bolts to the tightening shank. The tightening shank of bolt can be installed in the main spindle by the automatic tool changer. After one part A is finished with a machining center, the tightening shank of bolt takes out some bolts from the bolt stocker, and can tighten with some bolts between the part A and another part B. The part B is supplied by a robot. At last, the part B is finished with the machining center. This system was evaluated by the experiments of positional and attitudinal deviations ; these are parallelism, squareness, concentricity and position between two parts. It is concluded from the results that ; (1)This system can assemble the plural parts with high positional and attitudinal deviations. (2)A product with complex form can be made with short time and low cost.

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NC programless machining which is realized by the virtual copy milling system have been demonstrated. In the virtual copy milling system which is developed in this study, a stylus and a master model in copy miling are defined as geometrical surface models, the stylus motion corresponding to the tool motion is simulated by applying copy milling principle. This method is simple enough to generate the tool motion in real time, because it detects only the collision between the stylus and the master model which are defined. Experimental cutting have been succeeded to show that the virtual copy milling system is able to perform NC programless milling of sculptured surface. The real time tool path generation accomplished by this system aims to be used for the adaptation of cutting conditions such as depth of cut and feed speed to maintain stable machining. The adaptation of cutting conditions is an important function to realize an autonomous NC machine tool towards 21st century.

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The purpose of this study is to develop high efficient electrodes for the wet optical sensor by the use of various manufacturing processes of the thermal apraying method, the light been melting method, cooling method and so on. From experimental results, it was clear that the photoeffect characteristics of the remelting electrodes were higher than that of sprayed coating electrodes. Especially, the best film which absorbed the light could be made by the methanol cooling after melting of the spraying deposit.

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Several types of non-destructive testing method are used for detecting weld defects. Because the X-ray radiographic testing method is particularly useful in inspecting the inside of weld metal, it is often used in industries. However, since skilled inspectors for X-ray radiographic testing are gradually decreasing, recently several methods to detect weld defects from films automatically have been investigated to improve the quality of detection results. However, a X-ray film involves a number of noise, and defect images show very low contrast and various shape in spite of the same kinds of defect. Moreover, boundaries between defect image and background are unclear, and it makes difficult to automate the inspection of X-ray films. If a type of detected defect image is judges by expert system or neural network which learns a rule of professional inspector, the boundaries of defect image has to be detected like recognizing by human's(inspector's)sense of vision. Therefore, in this study, new image processing applied the genetic algorithms which has been investigated on the computer science for search problem were constructed, and applied to detection of defect boundaries in detail.

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This paper describes about the method to decide hypotheses priority ranking by memory, COCOM. In order to increase the reasoning efficiency of Reasoning to Anticipate the Future(RAF)that controls AGVs(Automated Guided Vehicles)in a decentralized autonomous FMS(Flexible Manufacturing Systems). COCOM includes the memory that shows the past production conditions and the AGV actions. By using the memory, COCOM changes the hypotheses by giving the first priority ranking to the hypothesis that is likely to become a true hypothesis. COCOM was applied to the decentralized autonomous FMS which was constructed in a computer. As a result, the number of changing a true hypothesis was reduced, compared with the conventional reasoning.

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A novel method was developed to design a stick-free guideway for a ticket alignment unit in an automatic checking and collecting machine. In a ticket alignment unit, tickets in various orientations are aligned by being transferred along a guideway. Conventionally, using either an empirical or an experimental approach, the guideway is designed to transfer the tickets smoothly. In the proposed method, the stick-free guideway is designed by analyzing the reaction forces from the guideway wall to the ticket. Design maps made by this method and some experimental results are presented.

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The reduction of vibration and noise is getting more and more significant in machine design, because it is accepted as a measure of quality. Thin plate structures are normally used for the housing of machines and instruments, and their vibration originates so-called structure-borne noise. From these view points, a method of optimum design of thin-plates for low noise in developed. The finite element vibration analysis and the boundary element acoustic analysis are combined and used to evaluate the sound power radiated from the plate, and it is minimized with respect to the thickness distribution of the plate. The result is compared with the plate of low vibration and the similarity of the methods is discussed.

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By using a tube law, which is the relationship between cross sectional area of a collapsible tube and transmural pressure, that is, the pressure difference of the inside from the outside of its wall, coupled problem between flow in the tube and its wall deformation can be formulated easily. In this paper a numerical method for calculating two-dimensional deformation of the tube and comparison with experimental results are reported. The calculation results are compared with those of ref.(6)to show validity of our calculation method in which the tube wall thickness is taken into account for contact behavior of the tube wall. In the experiment we use silicone rubber tubes as the collapsible tube. The tube's cross sectional shape is visualized by using laser light sheet method. It is shown experimentally that the tube law calculated by dividing inner volume of the tube by its length has large error in the wall contact region. In the tube law calculated in ref.(6), the tube wall thickness is not treated in rigorous way in the wall contact region. But according to our results, effect of the wall thickness on the tube law is not negligible in the contact region.

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