This paper deals with buckling of thin-walled cylindrical shells under compression. It is well-known that axially compressed cylindrical shells have buckling behavior which is very sensitive to initial geometric imperfections. However, current approaches using mathematical algorithms to optimize the linearized classical critical loads with respect to many design variables, generally ignore the potential reductions in elastic load carrying capacities that result from the initial imperfections. They present major problems for incorporation into design processes and often involve excessive computational effort. Adopting 6-ply symmetric, glass-epoxy cylindrical shells, the present paper carries out classical buckling analysis for perfect shells and nonlinear analysis for imperfect shells. In addition the present paper applies an alternative lower bound design concept called the reduced stiffness method. By confirming the correspondence between the lower bounds of nonlinear buckling analysis and the reduced stiffness analysis, it suggested that the reduced stiffness method could provide an important basis for design.

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The 2003 Tokachi-Oki earthquake caused severe damage to oil storage tanks due to liquid sloshing. Seven single-deck floating roofs had experienced structural problems as evidenced by sinking failure in large diameter tanks at the refinery in Tomakomai, Japan. The pontoons of the floating roofs might be buckled due to circumferential bending moment during the sloshing. The content in the tank was spilled on the floating roof from small failures which were caused in the welding joints of pontoon bottom plate by the buckling. Then the floating roof began to lose buoyancy and submerged into the content slowly. The authors had reported the buckling strength of the pontoons subjected to circumferential bending load in the previous paper. This paper presents the buckling strength of the pontoons subjected to both circumferential and radial bending load. The axisymmetric shell finite element method is used in the analysis. Linear elastic bifurcation buckling analysis is carried out and the buckling characteristics of the pontoon with ring stiffeners are investigated.

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Nonlinear responses of surface waves in square and rectangular tanks subjected to horizontal excitation along an oblique direction are investigated. When the direction of excitation is close to the diagonal line of the tank cross section, two sloshing modes (1,0) and (0,1) are directly excited and they also interact with each other due to nonlinear coupled terms. In the theoretical analysis, we derive modal equations of motion for the six sloshing modes with linear damping incorporated. Then, van der Pol's method is employed to determine the frequency response curves. Hopf bifurcations occur and amplitude modulated motions including chaotic vibrations appear depending on the excitation amplitude and frequency. The theoretical results were also observed in experiments.

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This study proposes a nonlinear vibration-response analysis method of cylindrical water storage tanks allowing coupling with the water in the tanks to be considered, and then demonstrates the proposed method can adequately simulate the experimental vibration response of tanks such as oval-type vibration. In addition, Application of the method to numerical experiment for the tanks during large input excitation, which can be hardly conducted by popular experimental equipment, is proposed. From the virtually experimental results, behavior of oval-type vibration and mechanism of occurrence of buckling is discussed.

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The nonlinear liquid motion in a partially filled cylindrical tank with two eccentric core barrels is investigated. The nonlinearity of the liquid surface oscillation is considered in the response analysis of the sloshing motion. Basic equations are derived by employing the variational principle. The nonlinear ordinary differential equations governing the liquid surface oscillation are then derived by applying Galerkin's method to the basic equations. The effects of the position and the radii of core barrels on liquid surface oscillation are discussed. The time histories of the liquid surface displacement are calculated to the harmonic excitations. An experiment was conducted using model tanks. A good agreement was found between the theoretical and experimental results. It is shown that the nonlinear analysis is important for estimating the sloshing responses.

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The Karman wake remains a classical paradigmatic system for the study of fluid dynamic systems. It exhibits, at once, the simple periodic oscillator form that complex flow around a bluff body can take; while at the same time exploding into complex dynamics when the stable oscillator is perturbed by external forcing. It is not surprising, then, that in practical applications, e.g. VIV and control, empirical relations are still used when estimation of VIV amplitudes are needed for design purposes. This paper, and in particular, the talk itself, investigates the influence and contribution of nonlinear dynamics to our understanding of the Karman wake dynamics and vortex-structure interaction in general. Much work has been done, 'proving' that the Karman wake behaves often like a low dimensional nonlinear system. The van der Poly oscillator exhibits many of the characteristics of the Karman wake-at least qualitatively. Lock-in, quasi-periodicity and chaos have been found. Yet, while qualitative agreement has been shown, quantitative comparison remains to be presented. The greatest challenge appears to be lack of a simple but realistic model for the Karman wake-if such a model exists. It is proposed that the full potential of recent developments recent in nonlinear dynamics is yet to be exploited.

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The effect of spiral fin around a bare tube on aerodynamic noise was experimentally investigated. This fin was made from a thin plate and mounted spirally around a bare tube surface. We measured the intensity of velocity fluctuation, the spectrum of velocity fluctuation, the coherence distribution in the spanwise direction and the spectra of sound pressure level of noises. As a result it was made clear that the periodic velocity fluctuation caused by Karman vortex was observed in the wake of the fin tube although the fin mounted around a bare tube. The large scale vortices in the spanwise direction were formed in the wake of the fin tube. Aeolian tone induced by Karman vortex shedding was observed in the case of fin tube. However, as the pitch of the fins decreased, the peak levels of spectra of sound pressure level decreased.

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In the present paper the attention is focused on the symmetric vortex shedding from In-line tube banks on acoustic resonance which occurred in the two-dimensional model of boiler. We measured a spectrum, phase delay of velocity fluctuations in the tube banks, sound pressure level. As a result it was made clear that the symmetric vortex was clearly formed even in the case of Reynolds number, based on mean gap velocity, of about 1.1×10^4 with acoustic resonance in the longitudinal direction of the duct. The frequency of symmetric vortex shedding became 3-4 times as large as the frequency of natural vortex shedding in the tube banks.

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Free vibration tests of a sphere tethered in a vertical water tunnel were conducted at high Reynolds numbers. A 2m×2m square-section water tunnel and a sphere model of diameter 0.2m were used. Periodic vibrations of swirling mode were observed at sub-critical Reynolds numbers and the sphere drew circular or elliptical trajectories in the plane perpendicular to flow. Violent and less periodic vibrations were observed at the critical Reynolds number and the sphere contacted the side wall of the water tunnel; showing that the maximum displacement was well in excess of 4.5 times the sphere diameter.

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In this paper, we have addressed the vortex-induced transverse vibration of a spring-supported circular cylinder in a narrow channel. The characteristics of the two-dimensional laminar flow in a narrow channel depend on the oscillations of the cylinder. In experiments using the dynamical similar model, we clarified the effect of channel wall on the lock-in phenomena and we observed, as the spring stiffness becomes weak, a constant component (DC Offset) included in the time history of the cylinder displacement. Furthermore, the experimental results were compared with the numerical results.

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Coil springs are often used in industrial fields, such as chemical plants or nuclear power plants, in order to suppress structure movements or islolate the structures from undesired vibration. A coil spring can be seen as an assembly of multiple rings, and is often exposed to fluid flow, which will cause vibration of a coil spring and consequent failures. In this study, a part of a coil spring is extracted as a ring and the flow induced vibration of a ring is analyzed. As a first step, a ring is expressed as two circular or elliptic cylinders in tandem subjected to uniform flow. Fluid-structure interaction analyses are conducted by using a CFD software ANSYS, and vortex-induced vibrations are evaluated changing the pitch and aspect ratio of cylinders.

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An estimated damping ratio is used to evaluate the occurrence of the fluid-elastic instability. However, many structures contain some nonlinearity, especially in their damping ratios. Then, it is a great problem which value is used for the estimation of the critical flow velocity. When the nonlinear damping is estimated as a function of the vibration amplitude of tubes, vibrations of a tube with the negative damping due to the fluid flow have some limited amplitude if the nonlinear damping trend is strong. It is a limit cycle oscillation. This report shows an approximate solution by using a polynomial function, and compared with time-series simulation results.

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This research aims at proposing an intelligent flight control system which makes unmanned aerial vehicles tolerant of actuator faults. To make the unmanned system downsizing and low-cost, this study focuses on keeping the redundancy by software approach. The purpose of this study is to establish the systematic learning-based design method of control system with the evaluation function based on control purpose. The proposed technique adds to normal flight control system with detection, identification, and accommodation mechanisms. Each mechanism consists of neural network. In this study, the availability of the proposed system is verified by six-degree-of-freedom nonlinear simulation.

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The overturning possibility for the vehicle running at very high speed subjected to the base excitation is investigated. One-half of the whole vehicle is analytically modeled. The vehicle consists of the body, the truck and the wheelset. The body and the truck have 3 degrees of freedom (horizontal, vertical and rolling direction) respectively, and the wheelet has 1 degree of freedom (horizontal direction). Considering the stoppers, the springs between the body and the truck, and that between the truck and the wheelset are treated by the nonlinear springs. The creep force between the flange of the wheel and the rail are considered. The vibrational behavior of the vehicle is calculated when the vehicle is subjected to the actual seismic input in horizontal and vertical directions simultaneously. The possibility of rollover of the vehicle is evaluated by "risk rate of rollover". The risk rate of rollover of the running vehicle is investigated both in a straight track and a curve track.

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In this research, we use a chain model causing soliton in which many pendulums aligned in two lines without contact are magnetically coupled with each other. The discrete nonlinear schrodinger equations derived from the equation of motion show that an envelope soliton and a dark soliton occur, depending on the parameters such as the wave number and the distance of pendulums. The above theoretical results of the propagating waveform and the range of causing an envelope soliton wave were confirmed numerically.

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In order to get insight into the physiological response under mental stress, we applied infrared thermography for assessing the distribution of temperature over the surface of face. Five young adults were subjected to 30-minutes typing using personal computer and also 30-minutes arithmetic as stressors. The temperature measurement was conducted with 3-minutes interval during the test. Skin temperature around nose was found to be most sensitive over the surface of face under the two stressors. The temperature around nose was found to decrease markedly 3 minutes after the start of typing and of arithmetic as well in every subject. After 6 minutes, the changes in nose temperature showed considerable scattering from person to person.

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In this study, relationships between nose surface temperature and salivary amylase were examined in image stimulation stress. The infrared thermography and the salivary amylase monitor were used for the measurement of the surface temperature and salivary amylase, respectively. As a result, nose surface temperature was decreased immediately after onset of the stress load, on the contrary salivary amylase was increased. These responses are considered to be due to the excitement of sympathetic nerve. It might be useful to examine these changes immediately after stress load to understand the degree of stress.

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This study investigated the effect of the stretch pole exercise in young and elderly groups on the range of the motion at shoulder joint, sitting trunk flexion, standing posture, EEG, and mental factors. After the stretch pole exercise, the range of motion at shoulder joint, sitting trunk flexion and α land α 3 in EEG increased in each group. The feeling after the stretch pole exercise in elderly group for relax, and loose of muscle were obtained of comfortable.

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Recently, a system which can monitor a car driver's biological condition and warn the driver of drowsiness is being proposed. Many researchers have presented evidence that biological signals like brain waves, pulsation waves, and cardiac beat, are different between a normal state and a drinking state of a person beforehand. However, current systems to measure those signals are assumed to be used in a laboratory or with invasive monitoring. A basic theory of the system that prevents drunken driving beforehand is constructed by establishing a new algorithm that distinguishes the person's state and ordinary drinking.

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This study measured the characteristics of exert muscle strength using a new made playground equipment and assessed the pleasure on the proposed new game for elderly. From EMG analysis, it was appeared that the tibialis anterior and rectus femoris of lower limb was used mainly during the new game, and the exerted muscle strength was approximate value at the movement of human gait. The subjective evaluation of the pleasure of the proposed new game was high scores in elderly. Therefore, it was proved that the new playground equipment and its game have remarkable effect on the lower limb exercise in elderly with pleasure and safety.

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Drink bottle shapes are considered in this study from the viewpoint of Kansei engineering. Nine different bottle models, that imitate PET bottles widely used for soft drinks, were fabricated and are used in the test. The impressions over the bottle model surfaces are targeted by surveying and collecting human reactions on the twelve sets of word (adjective) pairs from examinees. After applying some statistical treatments, such as the semantic differential and factor analysis methods, the general tendency of human emotional reactions to the bottle shapes are discussed.

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The simulation capability for intraoperative brain tissue deformation by the surgical procedures using computational Finite Element analysis is demonstrated in this paper. Our research group has been developing the patient-specific three-dimensional Finite Element brain deformation model consisting of precise anatomical structures. In the numerical simulation, the computation of the intraoperative cerebellum tissue deformation due to retraction with two kinds of spatulas for the operation on the posterior fossa surgery was conducted by ABAQUS/Explicit. The illustrative results successfully demonstrate the interaction between brain tissue and spatula. Moreover, it aims to achieve modeling the sense of touch and the shape of the brain tissue, and to simulate the retraction with the force feedback device.

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The accident that human falls down during a walking is an important problem in Japan where the aged society is rushing in. In addition, a person nearly 6,000 loses their life by a fall accident every year. In this study is given categories as the risk factor that an accident is easy to occur by a fall, we realizes that affinity is always most suitable even if we can observe what kind of change at the foot part and hips where sensor instolled footwear into about footwear and affinity of the floor side. At the time of the walking, an anglur acceleration change is examine a for dangerous factor like a spectrum data by using an acceleration sensor singnals when we control the tach of sole at the floor side slippy condition, and floor side changes in what a sole controls.

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Elastic viscostic materials with fourteen kinds of hardness and stickiness were processed by mixing soft flour and hard flour with water, and comparison experiment between sensory evaluation by human perception and mechanical measurement was performed using the materials as analogy of excrement. It was found that human perceived hardness and stickiness of the material by maximum standardized value. Moreover, in case that the hardness of the elastic viscostic material was low, human's detection was superior to mechanical measurement.

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In this study, to seek the relationship between moving patterns and transport efficiency of a peristaltic pump, water in an open channel with peristalsis of a side wall is investigated by cellular automata and experiment. The rule for cellular automata derived by the principle of conservation of momentum and the continuity condition of water level is introduced to simulate long waves in the open channel and study the transport efficiency. The results show that a peristaltic pump transports water most effectively if the propagation speed of the side wall's displacement is nearly equal to the propagation speed of long waves.

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The phenomenon that the powder in the sound tube forms the particle pattern like the wind ripple is reported. In this study, the factors which influence the particle pattern formation is investigated experimentally by changing kinds of powder and sound particle velocity, and measuring the interval between the particle pattern formed by sound wave. As a result, the particle pattern can be formed if the sound particle velocity is more than a certain velocity, and the interval of the particle pattern becomes long in proportion to the sound particle velocity.

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In the present study, characteristics of the acoustic field in an enclosure bounded by fractal walls are investigated using Cellular Automata (CA). CA is a discrete system which consists of finite state variables arranged on uniform grid (cell). The dynamics of CA is expressed by temporary updating the states of cells according to the local interaction rules, defined among a cell and its neighbors. In this paper, the influence of fractal shaped boundary structure to the reverberation and sound absorption characteristics of an enclosure is investigated for two dimensional acoustic wave propagation model described by CA. Local rules are provided for the construction of fractal patterns as well as representation of wave propagation phenomena. It is known by the numerical simulations that the damping enhancement and also frequency-selective absorbing behavior is seen for specific fractal patterns and stage numbers.

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Artificial neural networks have been applied to pattern recognition, prediction and control, because they have abilities of learning, generalization and nonlinear mapping. These conventional neural networks have not had "intelligence" yet. Not so many researchers of neural networks have been reported that introduce the structural and functional characteristics of the brain obtained by the progress of neurophysiology. In this study, we focused on the cerebral neocortex, which deals with recognition, language and imagination, introduced its characteristics to neural networks and investigated the possibility of emerging its functional characteristics of the human brain.

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This paper describes the control method to excite a MDOF system at resonance frequency. When the excitation point is corresponded to the detection point in the MDOF system, the phase delay at a resonance point and the phase advancement at an anti-resonance point alternately appear in the vibration characteristics, and the phase delay becomes 90° at all the resonance frequencies. Then, if the controller that has the phase delay 90° in a wide frequency region is used, the self-excited vibration is generated at each resonance frequency. In addition, the self-excited vibration mode is freely switched by changing the frequency of a minute sine wave that gave the chance of the self-excited vibration.

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In the measures of the noise in the compartment, structure-acoustic analysis which considered vibration and noise is needed. For the noise reduction in the compartment, the sensitivity analysis that considered sound pressure of the evaluation point in the compartment directly is suggested, but it is sensitivity analysis based on CAE analysis in many cases, and, as for the example of sensitivity analysis based on an experiment measurement, it is rare. Therefore, in this study, I aim at suggesting sensitivity analysis for the noise reduction using measurement data and a structure change method.

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Recently, the concern for the low noise design of the hoisting machines has been growing. The structure of hoisting machine differ from general electric motors, and the influence of the noise radiated from the rotor is large. In this report, the experimental modal analysis and the numerical vibration noise analysis of the hoisting machine were carried out, and the high accuracy result was obtained. As a result, the characteristic of structure-borne sound radiated from the stator and rotor of hoisting machine by the electromagnetic force was clarified, and the low noise design of thin type hoisting machine was achieved.

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In a drum-type washing machine, when rotating speed exceeds 1000[rpm], the frame-panels cause elastic deformation and generate radiated noise. Recently, for the solution of such a problem, the researches used CAE are performed. In this work, first, we constructed a vibration analytical model that considered vibration mode of the frame-panel in order to evaluate the vibration and the radiated noise of a drum-type washing machine. Simulation results were quite similar to experimental results. Finally, using the constructed analytical model, design parameters tests to reduce the vibration of the machine subject were conducted. As a result, low-vibration design was proposed.

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A purpose of this research is to explain the relation of the sound and vibration mode by experimental modal analysis. A cylindrical shell that has clipping in the center part is used as test piece in this experiment. The natural frequencies and vibration mode of the test piece are obtained from impact hammer testing. When an impact point is a node of vibration mode, it decreases the sound pressure level of corresponding peak frequency. As the results, it is clear that the vibration mode correlates with the radiated sound.

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Vibration of bearing has been clarified theoretically in previous researches. However, research on vibration modes of the bearing structure mounted on an electric motor has never been conducted. In this paper, radial vibration of the bearing structure mounted on motor is examined by three different methods: a) finite element analysis b) experimental modal analysis under static condition, and c) operation modal analysis. Moreover, researches regarding the vibration effect of a bearing on the bearing structure under different grease condition were also carried out.

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This paper proposes an impulse testing by using a laser ablation. In conventional vibration testing by using an impulse hammer, excitation forces to structures have not been included in high frequency region. The laser ablation can be applied the excitation forces of ideal impulse wave form to the structure's excitation point. Therefore it is possible to measure the Frequency Response Function (FRF) including high frequency range in this method. A cantilever's FRF measurement by using the laser ablation is demonstrated in this study.

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In the vibration analysis that we use the Finite Element Model of automotive body, it will be hoped that promotion of efficiency of the measures planning for vibration reduction. However, we need much time in it because it is uncertainty that the effect on the body by modifying of transfer paths such as the body frames. Therefore I thought it allows the effective measures planning by making it clear that the response of the body contribute to what kind of vibration of transfer paths. This paper is written vibration analysis method and inspection of the validity using the sample model.

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Transfer Path Analysis (TPA) is frequently used for Noise and Vibration problems especially in vehicle development stage. TPA finds the input and transfer path having the major contribution to the evaluation output. The precision and the easiness of TPA analysis is strongly demanded in order to attain the noise reduction and to shorten the time length of design cycle. Recently, a new TPA technique based on operational analysis and the principal component analysis has been proposed. This paper focuses on the new TPA technique, and the investigation is carried out by comparing the new TPA with the conventional TPA.

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In this paper we aim to combine of driving stability and energy saving by using the camber mechanism. We used 1/6 model vehicle for the purpose. The cornering method was elected an effective five kinds in cornering and energy saving. The tire map of the model vehicle tire was made with a tire examination machine. From the examination of the model vehicle, cornering and energy saving are evaluated from the step response test and cornering performance test. As the best cornering, method of adding camber angle in the opposite direction of the back and forth wheel is performance important, and the method of adding the camber angle only to the rear wheel is practical important.

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Active safety technology of automobile is developed dramatically by introducing active control. At the same time, there is an increasing possibility of causing disharmony between human and machine. In this study, we present intelligent neural network control system of active steering, considering with cooperation of human-machine system. In this steering system, driver's steering has a priority over control output as far as spinning out can be prevented by his own ability. As a result of numerical simulations, it is demonstrated that the proposed system is effective.

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A steering command from the driver to an active steering vehicle can be excessive, especially in lower road friction conditions. The present paper discusses protection functions for active steering vehicles. The grip margin is defined as the residual tire force normalized by the radius of friction circle. The isotropic brush model is reanalyzed so that a cubic equation for the estimation of the grip margin can be obtained. A protection function similar to that used in fly-by-wire aircraft is developed for active steering. This protection continuously updates the upper bound for a steering command according to the present vehicle state and the estimated grip margin. The proposed scheme is simulated using CarSim and the numerical results show their basic functionalities.

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Steer by wire technology in automobile will bring feasibility of complex steering control that is impossible to carry out until now. If characteristics of steering system, which is fixed at present time, can be changed timely, it may assist a novice driver in his/her emergency driving. The objective of this paper is to find the possibility that lane change performance is improved with a variable characteristics steering system. Effect of a proportional, a differential and an integral control element on vehicle motion and steering behavior in emergency lane change are studied by computer simulation.

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This paper discusses an application of sliding mode control theories to remote automatic operation of skid steer vehicle. Since it is very hard to control the angular velocity of the left-right wheel directly by an operator at middle or high speed, we have already proposed a model reference sliding control system by using a virtual steer angle demanded from the operator. However, it was assumed that the moment around the center of gravity of the vehicle could be generated as a control input. In this paper, a control subsystem to generate the desired moment is investigated. The unknown tire/road friction property is estimated, then a wheel velocity servo controller is designed in which the reference velocity is determined by the estimated tire/road friction property.

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This paper deals with the influences of body stiffness on vehicle dynamics. The influence is investigated through the comparison of the theoretical model and experimental results. The theoretical model denotes 2D Vehicle model that takes two bending modes into consideration by experimental modal analysis. Beside, an experimental vehicle and a road simulator are built to observe the dynamical behavior of flexible vehicle. Then, we compared the dynamical behavior of the analytical model and the experimental vehicle to specify the influence of body stiffness on vehicle dynamics. The mechanism that the body stiffness influences on the vehicle dynamics is discussed.

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The purpose of the research is advancing the circling speed in steady circle test with formula SAE vehicle that we developed. The data base consisted of the result that was measured by the load movement distance in the experiments. The changing of the turning performance when changed the suspension setting was estimated by these data.

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These days, the searches for sustainable Personal Mobility Vehicle (PMV) are ongoing worldwide. The authors proposed the two-wheel vehicle which has two transformable modes; a two-wheel steering and two-wheel driving (2WS/2WD) bicycle and a stabilized parallel two-wheel vehicle. This paper investigates the 2WS/2WD bicycle and proposes the stabilization control. It shows that by steering rear wheel to the negative phase to the front and by driving rear wheel to the negative phase to the front, it cancels back and forth movement and reduces the roll angle.

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In this paper, we design a control system to stabilize a motorcycle during steady-state circular turning at the low speed. The nonlinear dynamical model of a rider-motorcycle system is derived and linearized to perform the eigenvalue analysis and the frequency response analysis. A reduced-order model that can be used to design the control system is derived on the basis of the frequency response analysis. The attitude stabilization control system is designed to assist the front steering by H_∞ control theory. It is verified that the H_∞ control system designed can stabilize the attitude of motorcycle against a front-steering torque disturbance during steady-state circular turning.

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In order to improve the riding comfort of railway vehicles, it is effective to suppress the vibration of the vertical bending mode. Therefore, the primary suspension damping force control system with variable axle damper is being developed, which can control its damping force continuously. This paper reports how the relationship between the natural frequency of the primary suspension and that of the first bending mode of the carbody influences the vibration reduction performance of this system. Numerical simulations and running tests have been carried out, and the results have shown that the efficiency of vibration suppression is dependent on that relationship.

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Large vehicle as a construction vehicle is bounced because of running rough road. This vibration bounces the cabin and transmits the driver. The driver gets tired and his efficiency of work grows worse. This paper examines reducing cab vertical acceleration to make it same level as others against a load variation with the active suspension system using the proposed method of designing a vibration control system. The controller was designed by applying the H-infinity control theory. The numerical simulation results show that the ride quality for driver improved by the active suspension.

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In recent years, many researches on semi-active suspension systems have been done to improve comfortableness and handling stability. In the previous research of our group, a control method of a semi-active suspenision system with actuator dynamics was proposed. But the system requires the states of the body and the damper, and the states should be measured. This paper proposes the method of designing an adaptive Variable Structure System (VSS) observer which can suppress the effect of disturbances for a semi-active suspension system with actuator dynamics. The performance of the estimation is confirmed to be very accurate by simulations and experiments.

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This study aims at achieving simultaneous realization of ride comfort and steering stability for vehicle semi-active suspension considering driving condition. In this study, we proposed the algorithm which can improve both ride comfort and steering stability considering human sensitivity and phase difference of vehicle body motion by separating control range in terms of frequency domain. In consideration of the above concepts, we designed frequency weightings and the criterion function in frequency domain. Furthermore, we proposed the design of the integrated controller adapted driving condition such as steering and road condition. And we confirmed utility of the suggestion technique through simulation.

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