Most of non-rubber type isolation systems apply frictional force. One of the famous non-rubber type isolation systems is Friction Pendulum Bearing (: FPB) system. When using friction pendulum system in the open air circumstances, some have pointed out that long term durability of the systems must have been taken into account and it might have been very difficult to maintain the coefficient of friction. In this study, dynamic motion of the isolated structure model with 4 of FPB systems are investigated, especially in in-plane mode, considering a variance of friction coefficient of one system, a distribution of the mass of superstructures. The result and the analysis of the shake table test using 3-storey steal-frame model is presented in this report.

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Most of non-rubber type isolation systems apply frictional force. One of the famous non-rubber type isolation systems is Friction Pendulum Bearing (: FPB) system. The superstructure supported lot of FPB systems may have produced the rotational motion from the dispersion of the frictional force. In this study, dynamic motion of the isolated structure model with 4 of Friction Pendulum Bearing systems are investigated, especially in in-plane mode, considering a variance of friction coefficient of one system, a distribution of the mass of superstructures. We carried out the shake table test using 3-storey steal-frame model. In this paper, the superstructure is considered in two models: the 4 material point frame model and the rigid body model. The experimental result of the shake table test using 3-storey steal-frame model was compared with the response analysis of those models.

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The excitation force produced by thermal bending was calculated as a couple of equivalent bending momentum, which causes an equivalent thermal bending shape. The unbalance produced by thermal bending was also calculated in consideration of stiffness of bearings and the rotor. We compared the calculated vibration with the measured vibration of a heater-mounted rotor. The calculation error of the vibration amplitude in resonance is about 12% at the loop of the vibration mode on a critical speed. We also compared the calculated result by this method with that by simple method, in which the eccentricity of the rotor at main bearings is zero. We found that in case of calculating a thermal bending unbalance of a rotor, which has more than three bearings and that bearings stiffness is low, we should consider the stiffness of bearings and the rotor to estimate a thermal bending rotor vibration.

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Full foam type seat cushion for vehicle is made of such elements as panel, foam pad, and surface seat and each element individually effects on dynamic vibration comfort performance during riding. The most important requirement is to reduce resonance magnification of seat in the frequencies close to 6 Hz, which is the natural frequency of the human body's internal organs. Conventionally, the prediction of the resonance frequency characteristics of the seat cushion has been seldom done by calculation at design stage before evaluation of prototype test. This paper reports that it becomes possible to predict vibration property of seat cushion at design stage by solving vibration equation, which is obtained by replacing seat cushion structure with vibration system model having spring element and damping element equivalent to designed seat cushion and by making graph of resonance frequency characteristics using calculation program provided in this paper.

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When a railway vehicle negotiates curved tracks at high-speeds, the car body collides with lateral bump/stop in the secondary suspension due to excess centrifugal force, and the ride comfort gets worse. In this situation, there is also a possibility that active suspension does not work effectively. This paper deals with the addition of centering control, which pulls the car body back to the central direction from the outer side, to the vibration control in the active suspension. Considering the difference in frequency range to be controlled between the vibration and centering controls, H_∞ control law is employed and an effective weighting function is offered for cooperation of the two controls. Numerical simulations show that cooperation can be realized in spite of the trade-off relation between the two controls. The cooperative work of both controls is confirmed in the experiment using a scaled half vehicle model under the condition with equivalent excess centrifugal force.

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In the previous paper, the simulated loci of high speed cornering are not correspond with the experimental results, because of the tire model is only used the sticking in Coulomb friction model. If the centrifugal force becomes larger than the cornering force of tires, the vehicle does not maintain the desired course. This demeanor includes the sticking and slipping condition of the tire. In order to simulate the trajectory at the high speed corner, this paper is assumed three stages of friction condition; the low kinetic friction force at the beginning of slipping, the period of kinetic friction force, and returning to the static friction at the small slip angle. In addition of the RR (Rear motor Rear drive) type vehicle, FF (Front motor Front drive) type with SSM (Sensor Steering Mechanism) and four-wheel steering mechanism is developed, and both robots run on the oval course at high speed. Numerical simulation and experimental results show the effectiveness of the presented friction model.

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At the first step, I studied the driver model in the drift cornering. At the second step, I studied the technique by which the performance of running in the vehicle at the drift cornering was improved. I have understood the driver is steered by feed back the body slip angle and the body slip angle velocity at the drift cornering. Moreover, I have understood importance in the vehicle movement performance improvement the cornering force characteristic where the maximum cornering force of the tire was exceeded.

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To reduce structural vibration of high-speed rotating optical disk drives, we developed an auto balancer. The auto balancer automatically corrects the imbalance when the spindle rotates; it consists of several balls in a groove on the spindle motor and insulators that support the rotating structure. We also developed a design method for the auto-balance mechanism. This method can determine the adequate resonance frequency, the damping ratio of the insulators, and the allowable tolerance in the eccentricity of the groove. It was found that the balancer reduces the vibration amplitude of the rotating structure by 80%.

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Flexible suspension system like bogie mechanism type suspension has become to be used for running equipment of crawler-type construction machine especially to improve the comfortability in riding. However, in the running equipment with bogie mechanism, there are many unclear points in the dynamic behavior and loads due to the complicacy. This paper describes a method for modeling of crawler-type running equipment with a bogie mechanism as a multibody system. By using the model, in traveling on a firm ground with a rectangular bump, some simulations to analyze the dynamic behavior are conducted and the acceleration at the operating seat position and the suspension forces are calculated. The simulation results are compared with experimental results and the validity of the simulation method is verified. And the dynamic behavior such as the time histories of suspension forces is discussed related to the behavior of track links and so on. This kind of simulation could be useful for designing and deciding the optimum running system under given environmental, economic and operational constraints.

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Elevators used in skyscrapers have very long main wire support ropes and elevator speed is very high, so it is feared that, when the buildings are vibrated by a strong wind or a big earthquake, the transverse vibration of the main wire ropes is resonant with the vibration of the buildings. Models were made of the dynamic systems of the main wire support rope and the building. These models are represented by the hyperbolic partial differential equations, which were solved numerically with a digital computer. A summary of the results is as follows: Not only the fundamental but also secondary vibration of the long main wire support rope used on high speed elevators are resonant with fundamental vibration of the building. Moreover, it was clarified that, when the speed of the elevator is as high as that of the transverse wave of the wire rope, there appears a standing wave near the forced point, which cases the elevator cage to vibrate.

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There are many different types of wharf constructed, i.e. Caisson type, sheet pile wall type and pier type. The natural period ratio between a pier type wharf and a crane is rather close to 1.0. Also the weight ratio between a pier type wharf and a crane is around 0.5 or higher. The behavior of container crane and pier type wharf during earthquake is affected by the interaction each other. Therefore, in this paper, to investigate the effect of the interaction between the container crane and pier type wharf, we carried out an excitation test on a 1/15 reduced scale test model of a container crane and a pier type wharf. And we proposed a simple double decked mass-spring model, The numerical simulation results showed good agreement with the shaking table excitation test results.

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In a pervious paper we proposed a new system for an active control hydro-pneumatic suspension which is composed of high speed on/off solenoid valves, instead of a proportional valve or servovalve systems commonly seen in conventional use. And the practicality of the proposed system has been confirmed. The choice of on/off valves driven in the digital mode, such as the pulse width modtilation method, provides the system economy and reliability. In this study, a preview control method is applied to the hydraulic active suspension in order to improve its damping performance. The dynamic characteristics of the system using the preview control in conjunction with a sky-hook control are investigated using experiment and simulation. These results are compared with those obtained, from a conventional sky-hook control, and the availability of the control method is confirmed.

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This paper introduces a variable resistance type energy regenerative suspension using PWM step-up chopper. The energy regenerative suspension has nonlinear characteristics with dead zone for low speed motion. Hence the energy is not regenerated nor it has damping force. In order to overcome this problem, a step-up chopper is introduced between the actuator and the charging circuit. This chopper is controlled by velocity-dependent PWM signal to improve the damping characteristics and the efficiency of the regenerative suspension. The suspension system changes its hight according to the carrier load. Hence linear AC motor is used to the isolation actuator. A simple experiment is performed. The results show better performance than the standard regenerative suspension.

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An improved shaking-table control method that can compensate the reaction force caused by a non-linear specimen in real-time has been developed. This method measures the reaction force and generates a drive force to cancel it. The compensation signal to generate the drive force is calculated by a reaction-force compensator, which consists of the inverse transfer function of the shaking-table actuating system, a filter to reduce the noise in the measured reaction-force signal, and a proportional element to stabilize the shaking-table characteristics. The motion of a shaking table loading a non-linear specimen was simulated. This simulation shows that the compensator effectively cancels the reaction force and that increasing the SN ratio of the measured reaction force increases this effect. Moreover, two means to measure the reaction force are presented. The first means are the loadcells between the table and the specimen. The second means are the loadcells between pistons and the table.

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This paper proposes a new Electric Power Steering (EPS) control strategy that enables remarkable progress on steering maneuverability for stationary vehicles. Using a conventional controller, undesirable steering vibration prevented us from reducing steering torque. To eliminate this vibration, we developed a new control strategy based on steering angular velocity control for specified frequency using a newly developed steering shaft angular-velocity observer. We experimented with this proposed control algorithm using a test vehicle and confirmed that it enables reduced steering torque without any perceived vibration for drivers from slow steering to rapid steering. Concerning the assist-map, the proposed control strategy enabled more than three times higher gradient compared with that of the conventional one. This proposed control strategy requires no supplemental sensors.

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This paper deals with a wave filtering method for a flexible beam using point sensors for the purpose of implementing an active wave control system. It is the purposes of this paper to present the novel wave filter which can be located at any position of the beam. Firstly, the design procedure of the wave filter using two or four point sensors is presented. When introducing four point sensors, the wave filter may be placed at an arbitrary location of the beam, while an approach with two point sensors has limitation of the sensor placement. Next, from a viewpoint of numerical analysis, the effect of near-fields on the wave filter accuracy is investigated. It is found that the newly proposed wave filter may extract the designated wave no matter how strong the near-field effect is. Finally, experiment of the wave filter is carried out, the accuracy as well as robustness of the wave filter being demonstrated.

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Magnetic resonance imaging (MRI) is a tomographical scanning system that has a strong magnetic field. In the MRI room, ferric materials and noisy electric circuits cannot be present or function. At an experiment that investigates a human brain function using the fMRI (functional MRI), such as the phase discrimination of temporal frequency between visual and auditory, it is difficult to measure the answering times and its time quantitatively. At this point of view, we have developed a new simple answering device. This device is made of the mouse that is popular at office. For the strong magnetic field, its circuit is removed except the clicking part. As it can be connected to a personal computer, we can measure the answering times and its time during the experiment using the fMRI. To do so, there are some problems to solve, such as the strong magnetic field. In this paper, the performance of the answering device is demonstrated by several basic experiments to solve these problems.

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In our conventional research, we proposed a new technique to Estimate the Smoothed value and the Differential value 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 noises by keeping the sudden shift of signals. In order to construct ESDS, we require the system that is globally uniform asymptotically stable at the origin. As the stable system, sliding mode system that has nonlinear switching function is used in order to compose ESDS. This sliding mode system is known as minimum time system, and it converges from the arbitrary initial states to the convergence point in minimum time. In this paper, we apply linear system and sliding mode system that has linear switching line to construct ESDS. As a result, we clarify the validity of our theorem and characteristics of ESDS.

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When both ends of the rotor are supported by self-aligning double-row ball bearings, the geometric nonlinearity appears due to the stiffening effect in elongation of the shaft if the movements of the bearings in the longitudinal direction are restricted. As the rotor becomes more slender, this nonlinearity becomes stronger. In this paper, we study unique nonlinear phenomena due to the strong nonlinear spring characteristics. When the shaft is supported horizontally, the difference in support stiffnesses and the asymmetrical nonlinearity appear due to the shift of the equilibrium position. By the influences of the internal resonance and the axial force, the nonlinear resonance phenomena become very complex. For example, a peak of resonance curves split into two peaks, these two peaks leave each other and then become a hard and a soft spring types, respectively, and almost periodic motions and chaotic vibration appear. We clarified these phenomena theoretically and experimentally.

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Jump phenomena are observed at high speed range in the case of overhead valve mechanism. To simulate these peculiar vibration problem, a single mass model has shortcoming, because it cannot represent another high frequency vibration during jump period. Therefore, six mass model including Hertzian theory and EHL theory at the contacting surface, is proposed. Measured data agree well with predicted data of new six model.

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This paper proposes the model based control system design for autonomous flight and guidance control of Radio-Controlled Helicopter. RC Helicoper has been studied with fuzzy and neural network approach, but it is so difficult for unmodel based control to stabilize it. The system identification techniques and model tuning approach are applied for RC helicopter system to obtain the mathmetical model. In order to realize the full automatic controlled RC helicopter, we have designed the attitude controller and altitude controller with LQG based Kalman filter and trajectory controller with SMC (Sliding Mode Control) for RC helicopter. It has been clarified that the proposed scheme for attitude control, altitude control and hovering control are very useful by way of the simulations and experiments.

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This paper presents a non-linear control of a magnetic levitation system without current feedback based on passivity of a system. The magnetic levitation system is essentially non-linear. However, most researchers are modeled it as a linear system. If the object is far from the equilibrium point, a linear controller cannot compensate large gap between the magnetic coil and the object levitation. Some applications such as magnetic levitation conveyance system require large levitation gap control. In such cases, the linear controller sometimes makes the system unstable. In this paper, a non-linear controller based on passivity is introduced. The magnetic levitation system is decomposed into two subsystems, electrical subsystem and mechanical subsystem. The non-linear controller is designed for each subsystem. Controller for the electrical subsystem is designed by using kinematic-energy-shaping and PID controller is used for the mechanical subsystem. The asymptotic stability of the closed-loop system is proved by Lyapunov stability theory. The derived controller needs position and velocity feedback but not current feedback. Numerical simulation and experimental results show the validity of the proposed non-linear controller.

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Regarding the control of head positioning in hard disk drives, one of the barriers to achieve high positioning accuracy is the effect of the vibrations from the several mechanical resonant modes of the actuator. Thc resonances of high order modes are regarded as uncertainty, so that the conventional control system cannot reduce vibrations caused by high-order resonant modes. In this study, our purpose was to design the control system that can suppress the vibration from high-order resonant modes. The proposed method can do this by designing both the controller and the structure simultaneously using vector locus of open-loop characteristics. The experimental results from application of this method to actual hard disk drives are presented. The measured data show that positioning accuracy at high-order resonant modes can be greatly improved by proposed method.

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The local fluid excitation force acting on a rotated square tube bundle having transverse pitch to diameter ratio of T/D=3.1, in a single-phase cross flow was measured, and the Normalized Power Spectral Density (NPSD) and the correlation length in the axial direction of a tube were examined. The fluid excitation force acting on the interior tube was from 3 times to 10 times larger than that acting on the upstream tube. The fluid force was almost fully developed after the third row. NPSD of the fluid excitation force could be almost plotted on a single universal curve. Regarding the lift direction, there was a peak in NPSD at fD/u∼O.3 caused by vortex shedding. Regarding the drag direction, there could be another peak in NPSD around twice the vortex shedding frequency. In the region of fD/u >0.5 where the effect of the vortex shedding was assumed to be small in the lift direction, the correlation length of the lift direction was approximately 1.1D. When vibration displacement amplitude was estimated using above mentioned NPSD and correlation length, they were proportional to around the third power of flow velocity.

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In this paper, sheet flutter in a narrow passage caused by fluid-structure interaction is studied. The sheet is considered as a combination of mass less beam elements, springs and discrete mass particles, in which the mass of each particle and spring coefficient are calculated based on the beam model. Equation of motion of the system is obtained by the calculation of fluid-dynamic and frictional forces acting on each element vibrating around its equilibrium point. The linearized equation of motion results in an eigenvalue analysis. In particular, we consider the fluctuating flow rate at the inlet as a new variable to eliminate frequency dependency on the coefficients of the characteristic equation. Therefore, the eigenvalue can be obtained directly from characteristic function without iteration by this method. Then, calculated results were compared with previously reported experimental results and the validity of the proposed method is verified.

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This paper presents a new experimental modal parameter estimation method to be applied to point symmetric structures, and shows an application to modeling of tires for passenger-cars. The method decomposes frequency response functions into the components of individual natural modes based upon Fourier transform algorithm in the circumferential direction of spatial domain at first, and then determines the modal parameters using the components of each natural mode. In this paper, we explain the theory of the method, and present a challenging application of the method to an actual tire for passenger-cars. The tire is experimentally identified about its dynamic characteristics under the free-free boundary condition, and the result of the identification is expressed as a set of spatial matrices. The number of degrees of freedom of the identified spatial matrices is 152. Finally, in order to demonstrate the validity of this model, we carry out a prediction analysis of the tire under a clamping boundary condition, and compare the result with experiment.

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We presents a tunable acoustic filter using a combination of functional acoustic elements such as an acoustic resistance, an acoustic inertance and an acoustic capacitance. Various acoustic structures can be provided through a combination of acoustic elements. Most of conventional acoustic structures can provide only fixed acoustic characteristics due to thier fixed structural parameters. We have studied tunable acoustic elements to solve this limitation. This paper proposed a compact impact drive actuator for an acoustic capacitance control. A proposed actuator is designed and integrated into an acoustic structure so as to save its occupied space. Acoustic filters will be demonstrated as a combination of tunable acoustic elements. Characteristics of a proposed tunable acoustic filter with developed compact actuators will be discussed through theoretical and experimental investigation.

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A relationship between a motion space and a constraint space is studied and a method for determination of their bases in order to represent vectors of velocities (twists) and forces (wrenches) in a computer program has been developed. The reciprocal product, which is a bilinear form, between a velocity space and a force space determines the relationship of reciprocal spaces which is invariant to the coordinate transformation. It is shown that the bases of a velocity space and a force space must be determined based only on this characteristic, but the selection of suitable reference coordinate systems helps to determine simple bases. As an example, the force analysis of a mechanism having multiple loops with different Lie algebras is discussed and it is shown that the representation of velocities and forces by means of the bases thus determined is effective for the analysis.

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Equations of motion for a wheelchair in consideration of road inclination and caster motion were derived premising the following three assumptions: (1)Zero slip angle at every tire is assumed since a wheelchair is considered to move slowly. (2)The inclination of a slope is gentle and changes smoothly. (3)No other external force and moment than constant drag and moment about the vertical axis act on a contact point of caster tire. From the second assumption, it was theoretically derived that the inclination of slope is dealt with by considering the inclined gravitational force at angles of the slope acting on a chair in a level plane. The equations of motion for a wheelchair with casters were numerically solved and experimentally verified by implementing the U-shaped turning tests.

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Improving signal to noise ratio is a key problem to detect early faults of machinery under environment noise conditions. An effective method is presented for improving the signal to noise ratio by the adaptive neural network. This paper has made a comparison of failure detect-ability between least-mean-square (LMS) algorithm and adaptive neural network under heavy environment noise conditions. Experiment results have shown that using adaptive neural network is an effective means to extract early symptoms of machine fault under heavy environment noises and low rotating speed conditions.

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The authors developed a human-like head robot WE-3 RV (W__-aseda E__-ye No. 3__- R__-efined V__-). It realized the pursuing motion in 3 D space using coordinated head-eye motion with V.O.R. (Vestibular-Ocular Reflex) as well as pursuing a motion in depth direction psing the angle of convergence between the two eyes. Moreover, it can express human like facial expressions using eyebrows, eyelids, lips, jaw, facial color and voice.

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This paper describes the mechanical design and the speech planning of an anthropomorphic talking robot WT-1R (W__-aseda T__-alker-No. 1__-R__-efined) for the production of consonant sounds. In 2000, we mechanically produced Japanese vowels (/a/, /i/, /u/, /e/, /o/) using a first robot WT-1 (W__-aseda T__-alker-No.1__-). In 2001, we developed a second robot WT-1R, which was improvement over WT-1's mechanisms for producing natural vowels and consonant sounds. WT-1R has articulators (the tongue, lips, teeth, nasal cavity and soft palate) and vocal organs (the lungs and vocal cords). The total DOF (degrees of freedom) is 15. Furthermore, we proposed the speech planning of WT-1R by considering the complicated phenomena of consonant sound as three parts (steady consonant sound, transient consonant sound and vowel). WT-1R could mechanically produce Japanese vowels (/a/, /i/, /u/, /e/, /o/), some consonant sounds (/s/, /h/, /m/, /p/) and continuous sound /waseda/.

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In this paper, a control method of robots for human-robot cooperative manipulation is investigated. We propose estimating human motion using the minimum jerk model for smooth cooperation. Using nonlinear least-squares method, we identify two parameters of the minimum-jerk model in real-time. The estimated position of the human hand is used to determine the desired position of the end-effector of the manipulator in virtual compliance control. The motion estimation enables robots to coordinate actively even for unknown trajectories of handled objects that human partners intend. We implemented the proposed method on an industrial 6-degree-of-freedom manipulator with a force sensor. In experiments of cooperative manipulation of a rubber pipe, the motion estimation improved human feeling in coordination. The improvement was quantitatively evaluated from the viewpoint of "unnecessary energy transfer."

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An adaptive multifinger gripper system was developed for underwater ROV. The system, named The Artifact 'K' apture Operator (TAKO) gripper, provides soft and adaptive envelope grasp with three articulated fingers. Each finger comprises five segments and performs like an octopus tentacle. The gripper has 15 segments in total, yet they are coordinately driven by one single motor and tendon mechanisms. This design allows the gripper system compact, light weight, and less expensive. The TAKO gripper is mounted on an underwater ROV named Triton that is a research oriented test platform developed at Santa Clara University. The TAKO-Triton integrated test was carried out successfully for the artifact pick-up operation from the bottom of the water.

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Study on Housekeeping Robot which puts away laundry is promoted in order to improve ability for handling a flexible object. This paper proposes the way of unfolding clothes and obtaining grasping points to generate unfolded state of clothes. There exists dynamical phenomenon that clothes is naturally unfolded by influence of gravity if it is hung up under clothes grasped at two points on its outline. Human skillfully deforms clothes by using this phenomenon as empirical knowledge and this is considered as a useful method to unfold clothes for a robot. At first, condition for determining grasping points to enable to unfold clothes is derived based on the phenomenon. Secondly, the task of deformation of clothes for unfolding including an action for restoring torsion on a sleeve of a shirt is described. Lastly, the validity of the proposed method is shown by experimental results.

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In case of finishing a variable lead screw, the grinding wheel contacts with the screw surface at one point. When the wheel generates the screw surface, and the contact point moves on the screw surface, the contact point forms a locus on the surface. Between the contact point locus and the next one, the generating profile error is established. In order to evaluate this generating profile error, this report shows a method for searching of relative mean curvature between the theoretical screw surface and the surface generated by the grinding wheel. The numerical analysis clarifies as follows. At the bottom and the tip of screw surface, the radius of relative mean curvature is small. As getting far away from the common perpendicular of the tool shaft and the screw axis, the radius of curvature increases.

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The purpose of this study is to examine a practical application of a finish rolling process using a screw-shaped tool to consolidate the surface layer of sintered Fe alloy gear teeth and to improve the load carrying capacity. In this paper, preliminary rolling experiments of sintered Fe alloy rollers are firstly done. The consolidation in the surface layer of rollers saturates by setting the amount of rolling stock 200 μm or more. Secondary finish rolling experiments of sintered Fe alloy gears are conducted using a screw-shaped tool with a standard tooth profile. The void rate in the surface layer of gear teeth can be decreased to the target level by adjusting the amount of rolling stock normal to the tooth surface 150 μm or more. Gears with a good tooth profile and a good surface finish are produced through the rolling process of P/M gears with a convex tooth profile. It is also confirmed that the tooth trace accuracy can be greatly improved by two way rolling pass.

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Small oil particles generated from lubricant of rolling bearings in HDD sometimes cause fatal problems as head crash. A labyrinth seal is, therefore, often used in HDD in order to prevent oil particles from scattering on the disk surface. In this paper, the seal performance of labyrinth seals for small oil particles is investigated, numerically and experimentally. Two types of a labyrinth seal are prepared. One is an annular seal and the other is a bent one. It was consequently found that the seal capability of a labyrinth seal is generated by the centrifugal force exerted on oil particles when they pass through the seal gap and that the passing rate of particles largely depends on the air flow rate through the seal gap.

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Aerostatic journal bearings with compound restrictors have been often used in high speed spindles because of low friction and high accuracy of motion. However, they also have disadvantages such as lower bearing stiffness and smaller load capacity than hydrostatic bearings. We, therefore, propose the method to increase bearing stiffness and load capacity by raising supply pressure to the medium pressure region. In this paper the dynamic characteristics of aerostatic journal bearings with compound restrictors in medium supply pressure region are investigated numerically and experimentally.

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The characteristics of surface topography have a great influence on the frictional features. Wavelength analysis for the frictional surface topography of rubber is an important method to elucidate the complicated frictional phenomena. In this paper, a method is proposed to evaluate the power spectral density function of the frictional surface topography of rubber under the reciprocating sliding conditions by using fractal dimension, and the relationship among fractal dimension, the friction coefficient and test conditions are examined. As abrasion patterns grew, the power spectra of long wavelength became larger and fractal dimensions were dec-reased. There was a proportional correlation between the fractal dimension and the friction coefficient. The equation of estimation on the friction coefficient with a high multiple correlation coefficient of 0.749 was represented from power spectrum function density by using multiple regression analysis. As a result of simulation on the wavy patterns that made use of fractal dimension and phase, the simulated wavy patterns were similar to the experimental results.

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Recursive propagation method is an information exchange procedure proposed by the authors for decentralized manufacturing resources in order to cope with various changes in the manufacturing environments. According to the information exchange procedure of the recursive propagation method, each resource can inform its revised plan to the other resources and obtain information about the influence caused on the whole system by itself when it changes its own production schedule. In this paper, the recursive propagation method is improved in order to reduce the time required for the information exchange among the resources. The validity and feasibility of the method proposed here are examined on a platform consisting of plural personal computers which can communicate by using UDP/IP on a network.

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Industrial design support system for eyeglasses frame, which permits a customer to participate in the industrial design process was developed to respond to the quickly changing and diversifying customers' requirements. Our system was developed, based on Interactive Evolutionary Computing (IEC) technique so that a customer can express his or her Kansei requirements through images by interacting with the system. It should be noted that the design of an eyeglasses frame cannot be determined alone, but must be determined considering if it looks good with the customers' face. In our system, the user evaluates each sample suggested by the system, and then narrows down the candidate gradually. Its usefulness was demonstrated by the operational experiments and additional questionnaires.

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Development of assistive technologies (ATs) includes many complicated difficulty, because it must be based on daily life of users with some disabilities. This paper describes bottlenecks in development process of ATs and their solutions. 10 cases of AT development processes were investigated, then the bottlenecks and their solutions were extracted from the investigations. The results revealed that developers were frustrated with gaps between developed devices and practical devices for the users. There were many bottlenecks for improving the developed devices to the practical devices. Discussion with AT developers resulted in indication of two paradigms for the solution. One is development process that includes solutions of each bottleneck predicted. Another paradigm is relationship with human society that includes outcome research, social system, thoughts of users and stakeholders. AT development research should consist of these two paradigms and will advance creating truly useful AT for the users.

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This paper presents a system analysis to study function and failure of snow melting machines. Since the snow melting machine has short history of about ten years for its development, the systematic design guideline has not been established well in order to shorten the development period and respond to diversify of the needs. Based upon such technical needs, an analysis is made first to clarify the function of the snow melting machine and express directional graphs of the model by the ISM and DEMATEL methods. Secondly, six hundred sets of data on malfunction of the machine are analyzed by using the matrix chart and co-relations existing among various types of malfunction are discussed.

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