Rapid technological development in many industrial branches requires increasing of the rotating machinery speed and performances. This tendency might be considered the main cause that induced numerous vibration troubles in the field of rotating machinery. Recently, in order to increase the machines performances the radial clearance between rotor and casing became smaller and smaller. As a result, severe vibration accidentally occurred in the rotating machinery systems. Especially in the case of high-speed domain, various kinds of vibration occurred, such as “synchronous vibration”, “sub-harmonic vibration”, etc. But, there is a lack of knowledge concerning such kind of problems, due to the complexity of the rubbing and the collision mechanisms. This paper presents a theoretical and experimental study of the rotor vibration due to the rubbing against casing for high-speeds regime, considering casing dynamics and different configurations of the casing.

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In rotating machinery, resonance phenomena occur with large amplitude in the vicinities of the major critical speeds. In this paper, a new vibration suppression method utilizing the discontinuous spring characteristics is proposed. This spring characteristic is made by additional springs with preload. This method has the following advantages : In designing these additional springs, we need not adjust their parameter values to the rotor stiffness and the system damping. The amplitude of vibration can be suppressed to the any desired levels. Although this method has a disadvantage that an almost periodic motion occurs above the major critical speed, two countermeasures are proposed to diminish it. We clarified these phenomena theoretically and experimentally.

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The magnetic damping force is generated by not only a rotating-conductor-type magnetic damper composed of a rotating conductor and a fixed magnet but also a rotating-magnet-type magnetic damper composed of a rotating magnet and a fixed conductor. In the previous report, it was demonstrated analytically and experimentally that a rotating-conductor-type magnetic damper for a rotating machine caused unstable vibrations at a rotating speed over the critical speed. In this report, the authors show that the rotation of the axisymmetric magnet on its axisymmetric axis affects the magnetic damping force very slightly by a simple experiment, and that a rotating-magnet-type magnetic damper for a rotating machine can be modeled by considering the whirling of the magnet only. As the reslt, the rotating-magnet-type magnetic damper never generates unstable vibrations analytically. The analytical results agree well with the experimental ones.

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The transfer stiffness coefficient method, which was developed in the previous report by introducing the concept of the substructure synthesis method into the computation process of the transfer influence coefficient method, is applied to a structure with closed loops in the system. Such a structure can not be analyzed easily by the transfer influence coefficient method. However, the transfer stiffness coefficient method becomes applicable to such a structure, since the cross-dynamic stiffness coefficient matrix is introduced to represent the relationship between the state variables of substructure. As a typical example of the structure with closed loops, an algorithm based on the transfer stiffness coefficient method is formulated for the free and forced vibration analyses of a framework structure constructed from some uniform beams. In the analysis, both the truss and rahmen structures are treated. The validity of the present algorithm concerning the computation efficiency and the computational accuracy is confirmed by comparing the numerical computational results obtained by the transfer stiffness coefficient method with those obtained by applying the finite element method and the transfer matrix method.

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This paper describes that eigen frequencies for two dimensional beam structures under gravity. Because the beam structures were consisted of extremely thin flexible components, the shapes of the structures were changed due to their self-weight. And both ends of the beam structures were assumed to be clamped, To analyze these phenomena, discrete equations using finite element in consideration with geometrical nonlinearity were derived as cubic simultaneous nonlinear differential equations. First, large static deformations of the structures due to gravity were calculated using the proposed FEM. Next, linear natural frequencies for the deformed structures were investigated. The calculated results for straight beams and shallow arches using the FEM were consistent with the theoretical results carried by authors previously. Further, the influences of self-weight on eigen frequencies of the structure which was comprised of three straight beams were clarified.

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This paper describes vibration analysis using finite element method for an elastic block supported by a nonlinear concentrated spring. This block is connected to another block by a linear concentrated spring. The restoring force of the nonlinear spring has cubic nonlinearity. In this system, resonance responses mainly involve nonlinearity due to two vibration modes. Finite element for the nonlinear spring is expressed. Then the nonlinear spring element and linear spring element are combined to the elastic blocks modeled by linear solid finite elements. Further, the discretized equations in physical coordinate are transformed into the nonlinear ordinary coupled differential equations using normal coordinate corresponding to linear natural modes. This transformation yields computation efficiency. Influences of Young's modulus on frequency responses are clarifed.

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The authors propose a new control method to synchronize nonlinear vibration systems simply by adding noise. It is found from a random dynamical point of view that a nonlinear vibration system and its copies subjected to a common sample process of noise are precisely synchronize with each other. The method works well with the saddle-node and pitchfork bifurcation arising in the forced Duffing system, and the Hopf bifurcation produced by the forced van der Pol system. The result shows that the noisy input results in purely random vibrations which are precisely synchronize with each other and that the synchronization is stracturally stable.

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The precise positioning stage is ordinary mounted on the vibration isolated table. For its stage, PID compensator is commonly implemented in the control loop and its parameter tuning is carried out through trial and error in the production field. This tuning easily introduces the tradeoff between the command and disturbance responses. Then, we have previously proposed the tuning formulas based on Kitamori's method. However, this calculating process was quite complex. In order to simplify the calculating process, this paper proposes that Kitamori's method should be applied using the open loop transfer function instead of the closed loop one. Firstly, the open loop transfer function of Kitamori's model is derived and the control strategy is clarified through the open loop frequency response. Secondary, the gain and phase margins are derived from Kitamori's open loop model. Finally, the denominator series expression is easily calculated by using the open loop transfer function and the same PID parameters that are derived from the closed transfer function can be quickly calculated.

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In order to communicate kinesthesic information, as well as visual and audio information, via computer network, we adopt the master-slave system that has been used in remote manipulation. The controller of the system via network should satisfy the following two requirements : a) the stability of the system can be guaranteed for any communication time delay, and b) the master controller can be designed independently of the slave controller. Several controllers have been proposed to meet the first condition, however, these controllers only guarantee smaller time delay than that estimated beforehand. This paper proposes a design method for a controller that satisfies both of the abovementioned requirements. Based on the small gain theorem, the stability criteria is derived such that each controller should be determined in order to make the gain of each complementary sensitivity function less than 1. The system designed by the proposed method can be stable for any time-varying communication delay and the controller of each manipulator can be designed even if we do not know the dynamics of the manipulator in a remote environment. The validity of the proposed method is confirmed by simulation.

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The authors propose a portable vibration-based generator consisting of a coil and a cylindrical permanent magnet rolling on an arced rail. The power produced by a relative motion between the magnet and the coil is increased by a mechanical resonance of the magnet-rail system. Since a natural frequency of a pendulum tends to be low, the generator is suitable for power generation from a low-frequency vibration such as a movement caused by a human walking motion. Following a discussion of an optimal design of the generator, a prototype is fabricated. The performance of the generator is examined through experiments using a vibration exciter that can imitate a vibration at a waist of a walking human. The results show that the generated power reaches 1.0 mW when a frequency and an amplitude of an excitation are 1.8 Hz and 2.5 m/s², respectively.

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Seismic response of the system is nonstationary random process since earthquake excitation. is nonstationary random process. It is not easy to obtain the statistical properties of nonstationary random response theoretically. Mean square value of the response is usually used to describe characteristic of random process. In this paper, integral of mean square value of the response during earthquake excitation is focused on and its simplified estimation method is proposed. Earthquake excitation is simulated by product of stationary random process and envelope function. Non-stationary mean square response is approximated by product of stationary mean square response and square of envelope function. Integral of mean square value of the response for single-degree-of-freedom system and two-degree-of-freedom system for some values of the damping ratio and the natural period are obtained. It is found that the proposed method gives exact value of integral of mean square value of the response.

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The purpose of this study is to develop the structural health monitoring system by using the bending wave propagation. We investigate the velocity of the bending wave, which is one of the characteristics of the wave propagation. In this paper, the rectangular aluminum thin plate is used in the experiment, which is a basic element of structures. The plate is excited sinusoidal at one point by the exciter, and the vibration data is measured by using two non-contact displacement sensors. The velocities of the bending wave are analyzed by wavelet transform analysis. Then we investigate the possibility of identification of damage by using bending wave propagation. As results, the velocities of the bending wave could be measured exactly by wavelet transform, and the proposal method was able to identify damage.

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The nonlinear vibrations of an elastic structure carrying a liquid-filled cylindrical tank are examined. Modal equations goveming the coupled motions of the structure and liquid sloshing are derived when the structure is subjected to a vertical sinusoidal excitation and when the natural frequency of the structure is equal to twice the natural frequency of the first axisymmetric mode of sloshing. This system behaves as an autoparametric system. Then, van der Pol's method is applied to the modal equations to determine the theoretical resonance curves. This demonstrates that the resonance curve for the liquid sloshing changes from a soft spring type to a hard spring type as the liquid level decreases. The structure's resonance curve has a flat shape for an appropriate liquid level. In experiments the theoretical resonance curves were quantitatively in agreement with the experimental results.

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The response of the autoparametric system consisting of an elastic structure and liquid sloshing in a cylindrical tank is investigated. The structure is subjected to a vertical sinusoidal excitation and there is an approximate relationship of the ratio 2 : 1 between the natural frequencies of the structure and liquid sloshing. The modal equations derived in the first report are used to examine the influence of the internal resonance ratio's deviation, or the detuning parameter. As a result, it is shown that amplitude modulated motions appear depending on the negative or positive value of the detuning parameter for high or low liquid level. The bifurcation analysis, Poincare maps and Lyapunov exponents show that amplitude modulated motions and chaotic oscillations can occur. In experiments the theoretical resonance curves were quantitatively in agreement with the experimental results.

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This paper deals with a theoretical study of in-plane parametric vibrations of a curved bellows subjected to oscillating internal fluid pressure excitation. In the theoretical analysis, the curved bellows is modeled by FEM (finite element method) using beam elements including the effects of internal fluid mass and dynamic fluid pressure. Mathieu's type equation is derived from the equation of motion of the curved bellows subjected to oscillating internal fluid pressure excitation. Natural frequencies of the curved bellows and parametric instability boundaries are examined theoretically. As a result, two types of parametric vibrations, longitudinal and transverse vibrations, occur to the curved bellows. The longitudinal-parametric instability regions become broader with increasing the axis curvature (curve angle) of the bellows. On the other hand, the transverse-parametric instability regions become narrower.

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A flow meter whose flow rate is of the order of 10^-9l/s is developed. The previous meter ⁽⁴⁾ having the same measuring principle has a lower measuring limit of 10^-7l/s due to the heat conduction effect In this study, a new meter having a reduced heat conduction was designed and it enables us to measure the flow rate as small as 2.2×10^-9l/s. Numerical simulation for this meter revealed that there are two different heat conduction effects on the flow meter performance, i.e., (i) the conduction through the tested fluid and (ii) the conduction through the channel wall of the meter. The latter has a serious effect on the flow meter performance at low flow rate. It has been shown that thermal diffusivity of the wall material smaller than that of tested fluid realizes the lower measurable flow rate significantly.

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The induction heating type rice cooker generates forces in the pot by heating, and the force is then used to generate ultrasonic vibration in the pot to ensure the cooked rice tastes good. This paper describes the results obtained through a study of ultrasonic vibration. (1) A three-layer, rice cooking pot with an aluminum layer sandwiched between stainless steel layers was made to vibrate as a results of longitudinal vibration of the stainless steel layers. (2) A strong resonance is generated through the bending deformation and longitudinal coupling mechanism of the rice cooking pot. In other words, the resonance is caused by the bending stress generated in the stainless steel layer by the coil force which is converted into a longitudinal excitation force.

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Magnetorheological (MR) fluids can vary the rheological characteristics according to applied magnetic field strength and have been applied to various kinds of devices such as dampers, cluches, etc. In this paper, typical characteristics of MR fluids were measured under two types of working modes, shear mode and pressure mode, which typically appear in MR devices. Shear stress in shear mode and pressure difference in pressure mode were measured on changing flow rate, magnetic flux density, types of MR fluids and gap through which MR fluids flowed in MR devices. Using the experimental result, the force generated by MR devices was modeled to each mode. As a result, it was shown that MR devices could be designed in respect of the gap and magnetomotive force of the magnetic coil in the devices on the condition that the maximum controllable force of MR devices was given.

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A traveling wave-type ultrasonic motor (USM) has a self-locking characteristic due to a static frictional force present when its power supply is turned off, because its rotor is pressed strongly to the stator in the USM. We propose a pulse width modulation (PWM) method in consideration of this self-locking characteristic in order to control the motion of USM. The vibration waveform and the driving characteristics of USM were examined experimentally at different switching frequencies under PWM. When the period of PWM switching pulse is longer than the time constant of the piezoelectric element in USM, the rest duration appears in the vibration waveform of USM. It was confirmed that the rotor speed of USM was approximately proportional to the duty ratio of the applied voltage under the condition of the low switching frequency of PWM, and the large torque was obtained even when the duty ratio was small.

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In non-destructive inspection, it is very important to know in-pipe corrosions form because its information is available to infer kind of corrosions and cause of corrosions. An ultrasonic flaw detection method is often used for because of easy operation. However measurement accuracy is not good. Especially it is very difficult to get accurate thickness information at complex corrosions area where there are multiple corrosions. In this paper, we proposed the algorithm to improve a measurement precision of ultrasonic flaw detection method by measuring multipoints data and frequency characteristics of ultrasonic wave signals. The wavelet analysis of ultrasonic echo is used in order to detect candidates of reflect wave from a crrosion. We applied the algorithm to a pipe with the natural corrosions which have complex form and showed the utility compared to thickness measurement method.

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Most heat treatment equipments that control a large area to uniform temperature are divided into two or more zones, and the temperature control of each zone is carried out individually. However, for two or more zones with time delay, nonlinearity, uncertainty, and unknown disturbance, it is difficult to control each zone to an uniform temperature. Therefore, we propose a master-slaves control that can make those temperature loci in agreement with high precision. The proposed method is designed based on model reference sliding-mode control (MRSMC). Experimental results illustrate the effectiveness of the proposed method with applying to the multi-zone cooling plate for chilling a 300 [mm] wafer. By the proposed method, the temperature range across the wafer in cooling process is reduced within ± 0.1 [°C].

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We have developed an adaptive reference filter to control a tip position of a wire-driven mechanism using electric motors. For the tip positioning control system following operational reference, we have to solve the problems of friction, wire slack and form state change of the tube covering the wires. We have proposed the reference filter, which compensates for the delay from motor reference to tip position caused by friction and wire slack. In this paper, we propose the adaptive reference filter, which estimates friction changed by tube shape and converts the coefficient of the reference filter. Experimental tests show that the new control method using the adaptive reference filter decreases position error to about 30-50% less than the conventional method.

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This paper presents a method for multi-moving target tracking with 2D laser range sensor (LRS) within indoor environment. Tracking candidates are extracted from LRS's output via heuristic rule and Interacting-multiple-model (IMM) estimator ; the heuristic rule extracts the forehand objects in the field of view of LRS while the IMM estimator does the curved line objects. Moving targets (i.e., moving curved-line objects) such as walking persons are found from the candidates, and they are tracked based on Kalman filter. An assignment algorithm in which a joint likelihood function is maximized provides the reliable data association related to multi-targets and multi-measurements in cluttered environments. A track masagement method is also presented to allow tracking multi-targets under their moving conditions such as temporal occlusion, crossing, merging and splitting conditions. An experimental result in which four walking persons were tracked in a corridor environment validates the proposed method.

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We have proposed a new technique to estimate the smoothed and differential values of the sensor inputs by using sliding mode system (ESDS). ESDS is one of the nonlinear digital filters, and it works very effectively to eliminate the impulsive noise by keeping the sudden shift of signals. However, because ESDS is nonlinear system, it is very difficult to clarify the behavior of system analytically. In this paper, we clarify the signal tracking performance of ESDS by performing phase plane analysis. As input signal, we assume the step function, direct function and quadratic function, and we show the signal tracking performance with discrete representation. At the same time, we discuss the limitation of its analysis by using phase plane.

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In this study, in order to extract the abnormal components in an unsteady signal, we first propose a wavelet instantaneous correlation (WIC) method that utilizes the signal to create a Real Mother Wavelet (RMW). Our approach then was applied to the extraction of a knock signal, and the following very encouraging results were obtained : 1) The RMW has two kinds, a complex type and a real type. A real type could be constructed by taking out the abnormal part from the signal, multiplying it by the window function and subtracting the average value from it. A complex type could be obtained by the Hilbert transform of the real type. 2) The Hanning window function was found to be comparatively better than the Cosine window and the Gaussian function from the viewpoint of the smoothness of the window function and the resolution of time and frequency. 3) The time of occurrence and the strength of the abnormal signals were able to be extracted simultaneously by thresholding the value of the WIC R (b).

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In this paper, as the first step of trajectory control of aerial vehicles for live-line maintenance work, by servo valve attached to the derricking cylinder, a trajectory control method of bucket in the vertical plane is discussed. Here, we reorganized the equation of motion for the aerial vehicle and linearized the servo value by introducing the current compensation. Based on these equations, we derived the simple model of the controlled variable corresponding to the altitude of the bucket gravity center and the control rule. Simulations demonstrate that current compensation can improve the precision of trajectory control effectively, and good results can be obtained for the changing of the bucket altitude and sinusoidal reference trajectory by using the proposed method.

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The improved high precision and high performance are required to antenna structures. However, this kind of structures tends to deform easily as their size is enlarged. Therefore, in order to keep the surface accuracy of antenna, it is important to estimate a surface configuration of antenna from limited information provided by embedded sensors in structural elements. This paper shows a fundamental examination about the static shape estimation of truss antennas. Two approaches of shape estimation are proposed to deal with the case where measurement points are limited to the distortion in a subset of truss elements. In the first approach, based on the static modal analysis, the modal expansion method, in which the surface deformation of antenna is expressed by summation of natural modal displacements is employed. In the second one, the polynomial approximation method is used based on the assumption that the temperature distribution acting on the antenna can be approximated by a low-order polynomial. In this method, to minimize the shape estimation error, the sensor placement can be determined by the optimal location technique including the singular value decomposition. Some numerical examples for the shape estimation of large truss antenna using the proposed estimation methods are illustrated in this paper. From the results of examples, the validity of the present approaches is verified.

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In structural design, the stiffest structure is considered optimal. However, a structure having flexible parts offers certain advantages over a rigid structure in terms of mechanical function criteria. A typical mechanical example is compliant mechanisms, which use the design concept of structural flexibility to achieve a specified motion. In this paper, a new topology optimization method is constructed based on the continuous approximation assumption of material distributions for the design of compliant mechanisms. First, the relaxation scheme of a design domain based on this assumption is briefly discussed. Next, structural flexibility is formulated using a mutual energy concept. A new objective function taking the ratio of the displacement at the input location to the displacement at the output location into consideration is proposed. A multi-objective optimization problem is formulated and its algorithm is constructed using Sequential Linear Programming (SLP). Finally, several numerical examples are presented in order to confirm the validity of the method proposed here.

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This paper discusses a control system design with various specifications in both the time-domain and the frequency-domain. First, a control system design is formulated as a multiobjective optimization problem, and it is transformed a fuzzy satisficing problem by introducing aspiration levels and unsatisfying functions. It is solved by a Genetic Algorithm (GA) interactively. Then, the proposed method is applied to the design of the two-degree-of-freedom LQI servo system with the virtual command signal. The effectiveness of the proposed method is demonstrated by a numerical example, which has an undesirable undershoot.

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Using the technical data of front engine rear wheel drive vehicle, the effects of DYC applied to turning vehicle over critical range are studied. Control signal is calculated by the automatic search algorism using 4 tires vehicle model. The results show that DYC is effective at critical range of turning vehicle, but is not effective over critical range. There is the limitation in DYC control to protect the running idle of inner driving wheel, and this limitation reduces the effects of DYC over critical range.

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In order to enhance the speed of wheel slip prevention control for railway vehicles, modeling of adhesion characteristics after saturation of adhesion force, which had hitherto not been performed with trains, was performed via a beam model. The behavior of adhesive force between the wheel and rail in a wet condition was examined with a brake performance test stand for an actual vehicle. Results of comparing the model and test values indicated that the beam model represented test values well. We propose the disturbance observer to estimate adhesion force. The disturbance observer was effective in estimating adhesion force that is difficult to measure directly.

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Increased deceleration in high-speed and high-density train operation worsens riding comfort and frequently causes wheel skids. This requires introduction of control engineering to upgrade control performance of the brake system on rolling stock. We are now studying a control method for mechanical brake that uses friction, a sort of non-linear element as the basis of brake force. One of our targets is to develop a brake control method that can control deceleration along with the decelerating pattern that optimizes riding comfort and prevents wheel skids. In this paper, a feedback control system of brake for decelerating pattern tracking is shown. At first, mathematical model of pneumatic, cylinder and friction coefficient are made up with considering non-linear property, parameter changing and dead time. Next, Smith's method is intoroduced as compensation of dead time. Finally, control effects of this system are confirmed with numerical simulation and experimental results.

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This paper presents a method to suppress the vertical bending vibration of railway vehicle carbody by using carbody-truck (or bogie) interaction. It is shown from the running test result of an actual Shinkansen vehicle that the bending vibration can greatly be reduced when the rigidity of carbody-truck connecting elements in the longitudinal direction (i.e., rubber bush rigidity of traction links and anti-yaw dampers) Kx is set at the optimum value. The mechanism of the effect to reduce such vibration is analyzed theoretically. As a result, it is found that the truck frames and wheelsets act as dynamic vibration absorbers against the bending vibration of carbody. A formula to adjust Kx to its suitable value is derived. The accuracy and validity of the formula is evaluated numerically.

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In this paper, a power assist system for an overhead crane is presented. This system is realized by measuring the swing angle of a crane, which is caused by the direct operation to the object, and by moving the trolley and girder in the desired direction. Operators can move a heavy object freely by slight force. In this paper, two kinds of controllers are proposed. One is a PD controller that emulates the dynamics of object with damping and it moves the object in proportional velocity to the operating force in steady-state. Another is a PID controller that maintains the velocity of object continuously after operators cease their force. Its dynamics, damping characteristics, steady-state and admissible condition of controller gain are discussed. This system is applied to an experimental overhead crane, and the effect of energy saved by the power assist is shown by measuring the heart rate of operator.

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The disabled can acquire driving licenses, if they have physical ability to transfer from wheelchair to car seat, and also to drive it with steering wheel, even if it requires any special supporting devices. However, transferring to a vehicle and driving with a steering wheel are very difficult tasks for people with severe disabilities such as damage on the cervical vertebrae, and therefore they are not able to acquire driving licenses. As a result, they do not have any mobility tools other than powered wheelchairs, which means their traveling ranges are limited. If they use automobiles that they can get on easily from their wheelchairs, and they can drive by joystick instead of steering wheel, it is greatly expected that their quality of life must be raised. This paper proposes such type of vehicle named EVD, and design of prototype and examines its feasibility and effectiveness.

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Response time is measured as a psychophysical quantity with the event related potentials P300 as physiological signals in order to evaluate the response properties in visual task of driving a road vehicle. It is examined for subjects in the electro-proof shield room to detect or recognize a target index in a foreground scene superimposed on the front view scene in a road vehicle that is a background scene. It is shown by ANOVA (analysis of variance) and quantitative analysis that what kinds of factors are sensitive to the response properties such as the appearance region, size and intensity of illumination of target index, and fixation task in foreground scene and speed of a road vehicle and demand of traffic in background scene. It is also seen that the event related potentials P300 explain the differences between the effect of speed of a road vehicle and demand of traffic in background scene.

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The aim of this paper is to explore and present proposal for the accident preventive element for safe driving. The method of this research is to consider about the effects of using a car-navigation on the visual-information management of elderly drivers from the experimental approach. The evaluation indexes are measuring the movement of the driver's fixation point, the reaction time and the visibility time of a navigation screen. The results show the following : (1) In usual operation, the move area of an elderly driver's eye-fixation point becomes small and the tendency to gaze at the front of a car. (2) If a navigation screen is installed near 15 degrees surround directions and 15 degrees of horizontal directions from the driver front, the reaction time will become short. (3) The factor of the character size in navigation information is effective in reduction of the visibility time of the elderly drivers under driving. (4) The factor “Blue” of the color in navigation information is expectable in reduction of the visibility time of elderly drivers.

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Recently, various types of robot hand have been researched and developed. Most of them are multiple finger types that have multiple joints. However, each mechanism of them is complex, and usually enough grip power can not be formed. It seems that the most important objective of them is to make human-like hands. However, sometimes, it is reasonable that robot hands should have functional mechanisms instead of human-like fingers. In this research, we developed an functional end-effector (hand) that has more practical use. It has two parallel fingers that has a large grasping power. It includes a functional mechanism of vision sensor and belt conveyers, which are not in human hand. Experiments verified each function, such as the grasping mechanism, the vision sensor's mechanism and the belt conveyer mechanism.

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New architectures of manufacturing systems have been proposed aiming at realizing more flexible control structures of manufacturing systems which can cope with dynamic changes in volume and variety of products. They are so called as holonic manufacturing systems, autonomous distributed manufacturing systems, random manufacturing systems and biological manufacturing systems. The objective of the present research is to develop an integrated process planning and scheduling system which is applicable to the holonic manufacturing systems. In the previous paper, a systematic method is proposed to select suitable sequences of machining equipment, by applying the genetic algorithm (GA) and the dynamic programming (DP) methods. The method is extended, in the present paper, to consider the production schedules of the machining equipment.

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This paper presents an algorithm for solving a multi-floor facility layout problem. The most apparent difference and also the potential difficulty in a multi-floor facility layout problem, compared to a single floor facility layout problem, are the problems regarding the placement of the vertical transportation equipments (elevators), which are to be used for vertical transportation occuring within the facility. Many solutions generated by algorithms presented for the multiple floor layout problems in the past had problems : irregular-shaped workshops and/or unnecessarily large unusable space (=dead space) within the facility. In this paper, we implement and improve Slicing Tree Structure for generating layout. Layout generated by using Slicing Tree Structure has a unique characteristic of making no dead spaces within the facility at all. We will present an algorithm, which generates near-optimal layout of workshops and elevators in a facility without dead space by improving the structure of Slicing Tree.

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An instrument capable of measuring arbitary dynamic NC tool path in three-dimensional space has been developed. The instrument has three rotating axes connected with two serial links. The rotational motion of the axes are measured by three rotary encoders. A precise steel ball is attached at the end of the second link, and a magnetic tool cup assembly, which is mounted to the machine tool spindle, attracts the steel ball. The purpose of this paper is to describe the principle and structure of the instrument, which was then subject to several measuring experiments. The results of these tests validate the new measuring system.

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Numerical simulations are systematically executed for pipe flanges with wide variety of nominal size by using finite element analysis, which can simulate the bolt-up process of a pipe flange connection. Effects of the gasket modeling method on the bolt-up simulation and the bolu-up procedure which can prevent open up deformation are evaluated. It is indicated that the simplified linear modeling of gasket, in which two different Young's moduli are used in loading and unloading, is valid for estimating the variations, of mean bolt preloads during bolting up operations. The bolt-up procedure, in which four bolts located 90 degrees apart each other are tightened uniformly with the target bolt preload at the installation process, is effective to prevent the open up deformation. Finally, the methodical guideline for bolt-up operation of pipe flange connections with joint sheet gasket or spiral wound gasket is proposed.

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It is important to analyze the deformation distribution on friction surface under friction condition in order to clarify growth and wear mechanism of the abrasion pattern of rubber. In this paper, the aspect of the contact surface under sliding friction of rubber and glass plate was observed, and it was tried that the displacement vectors on friction surface that abrasion pattern was created was calculated by the digital image correlation method. As a result, the displacement on contact surface of rubber repeated the reciprocating motion. As abrasion patterns grew, the amplitude of reciprocating motion increased and the period was long. Even if the position of friction direction is different, the deformation of friction surface was similar the period and the amplitude, but there was a time lag. The normal strain and shearing strain on friction surface were calculated by the displacement vectors. Their strain repeated increase and decrease as well as the displacement. The range of strain increased, as the load was bigger.

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When the design point P₀ is given in the coordinate system C_s which consists of the line of centers and the axis of relative angular velocity, the plane S_t including the two peripheral velocities at P₀, the design reference line g_t which is the intersection line between the plane S_n perpendicular to the relative velocity V_rs0 at P₀ and the plane S_t and the design vertical C_n which is perpendicular to both gt and V_rs0 at P₀ are introduced. When a pair of paths of contact intersecting at the design point P₀ are given on the plane S_n, it is clarified that there is an equivalent rack which has the same pair of paths of contact and moves along g_t on the plane S_n and its dimensions (pitch, pressure angle, working depth, tooth thickness and so on) are calculated. Through designing the equivalent rack, the dimensions of gears, namely, the adequate inclination angles of the pair of paths of contact, the outside diameters and the face widths of the gear blanks, are designed to have tooth pairs with no topping and the required contact ratios which are calculated along the paths of contact in the region of mesh of the gear pair.

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Because the Flexible Spline is very thin in Strain Wave Gearing (SWG), it is easily broken. So, it is necessary to know the tooth root stress in SWG. However, the teeth in the small SWG are so tiny that tooth root stress can't be measured using strain gages. Therefore, in this report, the large SWG was used. In the first place, tooth root stress of Circular Spline in the large SWG was measured using strain gages. And load distribution on tooth flank was calculated using those measured values. And tooth bearings on Circular Spline were measured.

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In this paper the three kinds of skew gear pairs having uniform expression of contact condition similar to that of spur gears are discussed. The three kinds of skew gear pairs are the gears (gears I) having the tooth surface of involute helicoid group, and the gears (gears II) having the tooth surface of spherical involute group, and the gears (gears III) having a rotating tooth surface. The uniform expression is effective to clarifiy contact space image and contact characteristics of the skew gears, and to derive contact condition and solution of contact condition of the skew gears. First, tooth surface formation of the gears are discussed. Second, contact space image and contact characteristics of the skew gears are clarified. Third, contact condition and solution of contact condition are derived. This solution is very important in engineering and contributes to effective calculation of the zone of contact and the mating tooth surface. Finally, for examples, the solutions of contact condition of the skew gears are applied to the hourglass worm gears.

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This study proposes a new method on 3 D micro fabrication using a combination technique of nano-scale processing and wet chemical etching. The (100) surface of single crystal silicon was processed by using the mechanism of friction force microscope (FFM). A processed area was protuberated in the condition where normal load is less than 372 μN. The sample processed in this condition was etched by KOH solution. After the etching process, convex structure was made on processed area. The effect of processing condition on etch rate of processed area was studied. It was found that etch rate was changed with normal load, pitch of processing line and number of processing. Also, mechanism of height change was investigated under those conditions and some 3 D microstructure were fabricated by these results.

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This study proposes the 3 D micro-fabrication method on single crystal silicon using a focused ion beam (FIB) process with masking effect for chemical etching. It could be seen that the area processed by FIB remains though it was etched by KOH solution. The dependence of the masking effect on experimental conditions and its mechanism were studied by various parameters and structural analysis respectively. Some attempts to fabricate 3 D micro-structures were made based on these results. Subsequently, the costs can be decreased to fabricate 3 D micro-structure and the process be simplified compared to that using a traditional photoresist-masking method, owing to the simple sequential processes of the chemical etching followed by FIB process.

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This paper reports ultra fine plastic forming (nano forming) of hard brittle materials by indentation of diamond tools. Soda glass, firelite glass and quartz glass were examined by a nano indentation tester specially designed for this study. Two types of diamond tools were used for the experiment : one was a knife edge type tool and the other was a stamp type tool which was machined by a focused ion beam equipment. Indentation tests by the knife edge tool showed that glasses are available for ductile plastic deformation where no cracks are generated when indentation depth is smaller than their critical depth. Deformation characteristics of nano forming were found to be almost similar to macroscopic plastic work even on a hard brittle material. Indentation test of the stamp type tool succeeded in fabricating dot array structures on the glasses. Deformation of work material was however not uniform but depth of dots and density of cracks were distributed in a imprinted structure. Such distributions were explained by stress variation under the tool in imprinting.

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An improved single shear test is carried out to investigate shear characteristics of metal powder compact. By this experimental procedure, relation between the normal stress and shear stress at shear plane can be measured directly by shearing the powder compact at single plane with various normal stresses. Iron powder and stainless powder are tested and their shear fractures are investigated. Shear characteristics are evaluated by approximating relation between critical nominal friction coefficient and relative normal stress, where the relative normal stress is derived as the ratio with forming pressure and normal stress. As the result, the critical nominal friction coefficient at shear failure plane increases with increasing compact density, but it can be expressed without density dependence as a function of relative normal stress. Therefore the shear characteristics of powder compact with various compact densities can be expressed by this approximation.

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