The dynamical behavior of an viscoelastic body is known to be well described by fractional derivatives of the amount of deformation. The physical reason of this fact is the underlying fractal nature of the molecular structure of such materials. By using the Schiessel-Blumen ladder of mechanical system, it has been shown that the fractal structure would produce the asymptotic power law decay of the deformation, which is the most distinguished characteristics of fractional derivatives. So far, this has been shown by asymptotic behavior of the Laplace transform of the impulse response of the relaxation. Here, we generalize this result, and show that the exact solution of the impulse response function is obtained for a large class of parameter values in terms of confluent hypergeometric functions. The asymptotic expression is then readily obtained which shows the power law decay.

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The quasi-statical behavior and the nonlinear dynamical behavior of a viscoelastic (VE) column have been experimentally observed. Expressions for linear quasi-statical relationships between displacement and force of the model, in terms of the spring-pot model (statical model) that depends on the fractional derivative (FD) parameters q and c are obtained from the experimental results. Close inspection of the damping capacity which is obtained from the experimental results reveals that the damping capacity obeys fractional power law with respect to excitation frequency and exponential law with respect to compressive pre-strain. From these observations, we found that g and c of the FD model (dynamical model) with nonlinear spring term depend on the pre-strain ε_s when ε_s is relatively large.

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Rubber isolators are used for decreasing engineering vibration and noise. Many of rubber isolators are cross-linked rubbers filled with filler such as carbon black. The dynamic behaviors of the rubbers are nonlinear. It is difficult to analyze the nonlinear dynamic behaviors. We measured dynamic properties (storage shearmodulus, loss shear modulus, loss factor) of SBR filled in carbon black under various conditions of strains andfrequencies. In this paper, mechanical model composing of linear springs and linear dashpots and sliders is applied to dynamic behaviors of the rubber.

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CFRP is utilized as a material for the shank of boring bars, to achieve higher cutting performance than that of conventional steel shank bars or carbide shank bars. Natural frequencies of CFRP considered its anisotropy by the rule of mixture is calculated by FEM. The equivalent mass-spring method is proposed to estimate the loss factor of CFRP. Combination of ultra-high modulus carbon fiber and matrix resin formulated to have specific damping characteristics consistently gives both of high natural frequencies and high loss factors. The loss factors of CFRP boring bar are calculated based on the mode strain energy method. High damping CFRP boring bars can be stably used at higher surface speed with longer critical overhang without chatter vibration.

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Macroscopic loss factor for a sea-island type of polymer-based composite material is calculated by using the equivalent inclusion method combined with the Mori-Tanaka theorem. The effects of the loss factor and the elastic modulus of the island particle on the macroscopic loss factors of the composite are examined under the tensile applied stresses. The results obtained are compared with those calculated by the so-called modal strain energy method (MSE). Consequently, the present value of the macroscopic loss factor of the composite is good agreement with that of MSE result when the aspect ratio of particle becomes large, while both results are different from each other for smaller aspect ratio. Moreover, the contour maps of the macroscopic loss factor of the composite are calculated with respect to both magnitudes of the loss factor and the stiffness of the particle. The obtained map for smaller aspect ratio of the particle differs from that of MSE significantly.

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Macroscopic loss factors of a sea-island type polymer alloy are calculated by the use of the equivalent inclusion method combined with the Mori-Tanaka theorem. Effects of the shape of the island particles on the macroscopic loss factors of the polymer alloy are examined under the tensile applied stresse. Consequently, it is found that the polymer alloy whose value of the macroscopic loss factor is 5-10 times as large as one of the matrix polymer can be obtained by choosing the paticles whose aspect ratio is less than 0.1. Moreover, a value of the macroscopic elastic modulus of the polymer alloy can be maintained at one of the matrix polymer by adding glass particles whose aspect ratio is less than 1.0 into the matrix of the polymer alloy.

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A completely saturated styrene-isobutylene based thermoplastic elastomer, under the trade name SIBSTAR, has been produced at the industrial scale for the first time. Main grades are triblock copolymer in 1he form of styrene-isobutylene-styrene (SIBS) and diblock ropolymer, styrene-isobutylene (SIB) of Mn range 40,000 to 100,000. Due to polyisobutylene, which is as same structure as butyl rubber used as damping material, being a major component, SIBSTAR is superior in damping propaties. Due to its tiiermoplasticity, SIBSTAR can be processed as plastics into various shapes. A variety of useful applications are being developed for SIBTAR, for example viscoelasutic damper for construction and others.

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Planetary Airship System (PLAS) has been proposed as the platform of planetary exploration. One of the most feasible missions of the system is in the below crowd environment on the Venus. Airships do not need the energy to lift, can fly long period without landing, and have the safely and the redundancy. Therefore, PLAS is expected as a flying platform of the planetary observation. In the present study, the basic modeling and dynamics of the PLAS are analyzed. In addition, Input Shaping Control is employed to reduce pitching motion due to the thrusting.

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The tension of space tether system consists of on-orbital gradient of gravity and Satellite's centrifugal force. In case of tether systems with equal mass and cross section properties, tension and stress of tether have maximum value at the end of tether connected to the mother satellite. These values of stress increase as the space tether systems are designed on a large scale, and the destruction of tether systems could be anticipated in the extremum. To reduce these gradient of stress value, tapered cross section tether is proposed and is analyzed its performance of vibration and control of lateral motion. Numerical results show the behavior of the tapered cross section tether, and the wave-absorbing control to suppress the vibration are shown to effective.

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Active control is studied to suppress vibration of large solar panel for a Space Solar Power Satellite(SSPS) employing tether tension A model employed in the present study is a cantlevered flexible beam. An actuator is tether attached at the free end of the beam is employed for the control Algorithm. Results of numerical analysis show excellent controlled behavior. Some experimental results are also shown.

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This paper deals with the active vibration control of parallel solar panel-like structures supported by a rigid-body rotor like a space station. Two flexible plates are connected with each other by the electromagnetic actuators through the flexible arms. As a vibration control mechanism, the method using the interactive force between structures is used for controlling vibration of these plate structures. Then, these structures are expressed by the lumped parameter 3-DOF model using the reduced-order modeling method. To prevent so-called spillover, a second order low-pass filter is inserted in the control system. The pole assignment method is used to obtain feedback gain. Computer simulations and control experiments showed the effectiveness of presented control method.

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This paper deals with motion control of 1-link flexible arm, using sliding-mode control. An estimate of all state variables is indispensable for sliding-mode control. So, we use Kalman filter or VSS observer. According to the experimental study, it is confirmed that the flexible arm moves to desired position smoothly, and this control has high robustness against change of payload's mass. Also, we considered a trajectory control to move to desired position in arbitrary time, using switching hyper-plane on which a pair of imaginary poles exists. Key Words: Flexible Arm, Motion Control, Sliding-Mode Control, Kalman Filter, VSS Observer

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This paper presents a design procedure of Hoo controller for motion and bending-torsional coupled vibration of flexible robot arm. In the case that the robot arm does not hold the inertial center of the payload, it processes uncertain bending-torsional coupled vibrations which affect in the accuracy and the stability of the controller. In this research, H_∞ robust control design scheme taking account of parameter variations as structured uncertainties is utilized to describe the uncertainty in coupled vibration to guarantee robustness against such uncertainty. The superiority of the presented controller design method is certificated.

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Recently, visual feedback control has become important, in order for the mechanical system to recognize dynamic environ- ment and then to achieve their purpose task in real time. The purpose of this research is to sense the state of the 2 dimensional inverted pendulum by stereo vision of universal camera and to stabilize it by 2 link manipulator. To compensate the long sampling rate and lens distortion of CCD cameras, a multi-rate control is applied to manipulator servo control, and a neural networks is trained the relationship between a world coordinate and image coordinates. Also, the image processing is included the pendulum's dynamics to avoid the misrecognition. We verify the effect of the controller and the visual feedback with universal cameras through the experiment of stabilizing the pendulum.

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In this paper, we will propose mobile manipulator which has wide movable range and new method to predict a future ball position considering spin and friction of air. Our purpose is mainly establishment of basic method to predict a future ball state. It is very difficult to predict a future ball position. As ping-pong is said sport of speed, it is a speedy sport in which players strike together in less than 3 meter court. Hence, prediction must be performed in short time. Additionally, ball is easy to get air drag, and it affects ball dynamics. Especially, when spinning, we have to consider force of Mugnus effect, and therefore we have a lot of parameters that must be modeled.

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The purpose of this research is to build the control technique which can pass through the complicated submarine geographical feature with the group which consists of two or more underwater vehicles which receive a non-holonomic restraint in while changing formation form, and to verify the validity by the simulation.The underwater vehicle treated by this research assumed that has 6 flexibility and only 3 inputs.

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Several packages analyse a set of eigenvalues of rotor-bearing systems at given speeds. But it is still hard to identify each eigenvalue behaviours depending to speeds. We propose a solver which can continuously follow an eigenvalue modification by speed change. In our method, an eigenvalue and eigen vectors are replaced by state variables which difference are defined by the sliding mode control. Hence, the numerical integration provides variables grasping the exact value in any speed. We study on the eigenvalue analysis of the rotor supported by oil-film bearings and the critical speed calculation to demonstrate the effectiveness of our tenacious solver.

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This paper presents the way to improve the effect of dynamics education for mechanics majors by using their mental models. Mental model is the images reminded in the first stage in learning first matter. If the mental model obtained from experience of everyday life is applied to dynamics, although it becomes easy for us to imagine a phenomenon, wrong recognition about force or movement may be carried out. Under the suitable guidance based on their mental models, they could obtain a right and essential understanding of dynamics. In order to improve their mental models, we used bodily sensation type teaching materials and visualization of phenomena.

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In this paper, estimation method of velocity and acceleration of joints of robot using Radial Basis Function (RBF) interpolation is discussed. Identification algorism of system parameters of robot generally requires displacement, velocity and acceleration of all joints. However, some state variables such as velocity and acceleration of joint angles cannot be measured directly and should be estimated from measurable ones. In proposed estimation method, sampled displacement data are interpolated with RBFs and estimated velocity and acceleration are derived from analytical derivation of the interpolation. Simulation results show that estimated state variables agree well with actual ones when 40 sampled data and 601 RBFs are used in the estimation. Parameters of robot are calculated in an error of 0.33% using estimated variables.

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A basic research is being carried out on transport of liquid drop in electrostatic traveling field. A liquid drop conveyor consisting of parallel electrodes was constructed and four-phase traveling electrostatic wave was applied to the electrodes to transport liquid drop on the conveyer. The following were clarified by the experiment: (1) The liquid drop which straddled less than three electrode array could transport in the traveling wave field. (2) The mode of liquid transport was classified into two; synchronous region that liquid drop motion was synchronized with the wave and delayed region.

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In this paper, the newly system that is decrease aerodynamic drag for supersonic flywheel at atmosphere is described. We produced flywheel energy storage system, using a CFRP composite flywheel and a newly designed motor/generator. This system be able to keep the rotation speed that circumferential velocity is supersonic, due to their high tip speed, the flywheel must operated in the specific shroud with regard to rotor aerodynamic drag. The present time, their operate in vacuum container as a example of the specific shroud, but the drag is decreased, temperature of the motor and the bearings with flywheel is increased. Therefore we take doing to study for aerodynamics that we put a newly theory on the practice them. We find a method that flywheel ring is operated in correspond number of the floating shrouds to the maximum rotor speed, and the temperature of system is easy to eliminate at atmosphere. I make a try to take analogical reasoning on electric circuit.

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This paper describes a study of classifying the abnormal tension signals, observed in the draw-texturing machines, which correspond to various types of abnormal operating conditions. The wavelet transform with inhomogeneous shift sampling is used to extract the feature vectors from the tension signals. Then, the supervised self-organizing map (SOM) algorithm is performed on the feature vectors to carry out the classification of the signals. A quality index is defined to evaluate the classification performance of the proposed algorithm. The comparison of the results with those by a skilled engineer shows the consistency of the developed classifier.

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The purpose of this study is the early detection of the fatigue crack caused by In-line flow-induced vibration. The authors have tried to detect the minute unusual signals from the crack included in waveforms using wavelet transform. Then, it is necessary to remove the end-effects and the unacceptable noise in the wavelet transform for the effective diagnosis. In this paper, we succeeded in removing the end-effects and the noise from the waveform which were limited to steady-state waveforms and the unusual signals were periodical. As the result, it is possible to detect the minute unusual signals from the fatigue crack.

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An abnormal vibration is measured when lubricant in bearings is reduced. It is found that the abnormal vibration changes from intermittent low frequency vibration to steady high frequency vibration as the lubricant decrease. Repetition factors are used to detect abnormal vibrations. The repetition factors are normalized with the largest vibration amplitude of each frequency component. So this diagnosis method can detect intermittent vibration and small vibration on beginning of failure. This diagnosis methodis applied to measured vibration and demonstratedits availability.

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In this paper, we proposed new parameter identification technique using orthogonal functions to identify the density and the modulus of elasticity of each segment of the beam. Using orthogonal functions, we could consider the parameter distribution in identification and identified the distribution of the density and the modulus of elasticity with a few parameters. We applied the Legendre series and the Haar series for the uniform, the combined and the cracked beam. We checked the applicability of our technique for the parameter identification by the simulation and found the considerable reduction of the calculation time and good regularization ability.

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The purpose of this study is to improve the accuracy of the matrix tactile sensor and to confirm its usefulness. The matrix tactile sensor consists of 12 sensor elements. A single sensor element can measure the triaxial forces using the strain gauges. For raising accuracy of the measurement, we clarify the relationship between forces and strains based on the experiments, predict forces using the value of measured strains, and estimate the uncertainty of the measured strain values from the statistical point of view. These results suggest the actual measurement force value and the predicted force value show high coincidence. For confirming the usefulness of the matrix tactile sensor, we discuss about the detection of then center of gravity movement.

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In order to acquire the vibration information in 2-dimensional space, it was thought that vibrations in two axes should be simultaneously measured using two sensors. When vibrations in many directions are measured using the vibration pickup of a single axis, there is no simultaneity between the measured data. For this reason, it was thought that 2-dimensional measurement could not be performed. This paper reverses this common sense. In this paper, the RMS values in three places are measured at time to differ using the vibration pickup of a single axis, and the theoretical elucidation for obtaining the vibrating action in 2-dimensional space only from the measured values is performed. Next, we verify that the theory is correct by measuring the vibration of rotating machine which unbalance has generated. The display method of the vibration information in 2-dimensional space as a combination of elliptical orbits for every frequency component is proposed. On the orbit of vibration with two or more frequency components, the method of determining the rotation direction using the measured vibrating waveform is also proposed.

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Bolted joints are commonly used for many machines and structures. They sometimes suffere bolt loosening and may sometimes induce accidents. Therefore, bolt loosening detection techniques are essential for many machines and structures having bolted joints. Authors have proposed a new bolt loosening detection sensor using a natural frequency of a thin plate. The natural frequency is identified by admittance of piezoelectric elements attached to the plate without human commitments. However, this method requires function generator, voltage-current measurement circuit, A/D converter and computer with data processing software to identify the natural frequency. In this paper we propose an oscillator circuit which include piezoelectric elements as an easier natural frequency identification method. The oscillating frequency of the circuit is determined by the natural frequency of the plate. The relation between axial tension of the bolt and oscillating frequency is measured experimentally and validity of proposing method is confirmed.

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A three-dimensional shapes measuring system using an optical spatial modulator have been proposed. The system is composed of an optical spatial modulator from which grating patterns are projected on the surface of the object, a CCD camera controlled by a robot arm, and a computer. The patterns on the surface of the object were taken into the computer by the CCD camera, and the 3D coordinate of the surface of the object was calculated. Accuracy of vertical direction was improved using arbitrary position of camera.

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In order to disseminate distributed energy systems, an autonomous diagnosis of the system is imperative. The purpose of this study is to develop the diagnosis method using the fieldbus technology, which makes it possible to share much information of field devices. The authors constructed an experimental apparatus of a heat exchanging process, which is one of the key component of distributed energy systems and a measurement and control system with fieldbus devices. In this paper, the integration algorithm of the process diagnosis on the basis of the calculation of the overall heat transfer coefficient and the device monitoring using the statuses in the FOUNDATION fieldbus was developed and its effectiveness was confirmed experimentally.

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A method was developed to estimate bearing wear of seawater pumps in operation. Bearing wear is estimated from over-all value of shaft vibration measured by ultrasonic vibrometer, which can measure shaft vibration from outside the pump casing. A pump vibration analysis model was developed and validated by bearing wear tests using test apparatus. The change of shaft vibration in an actual pump by bearing wear was calculated using this analysis model.

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Control method is studied in this paper for the deployment of space tether using a reel device facility. The reel device consists of a drum type reel, a "wheel to simulate space environment, and a measuring device of the tether tension. A filtering device is designed to reduce noise contained in the tether tension measurement The velocity of the tether deployment is employed as an input and numerically simulated forces acting through tether are put into the wheel to simulate environment A control algoriflim of the Mission-Function control is employed in the experiment to control the deployment of tether in the present experiment Results of the experimental and numerical analyses have obtained to provide an excellent insight into performance of the tether reel device.

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We developed a new method for accurate estimation of the excitation force of an electric motor by inverse system using measured acceleration response. To solve this inverse problem, we employed an accelerometer to measure the accelerations of the supporting beams of the motor. In the experiment, the acceleration of a beam was measured when the motor was in operation. Additionally, the inverse system was created by using the equations of motion for both the motor and the supporting beams. The results obtained by this method agreed well with the results of the excitation force measured by using a load cell directly.

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A multiaxle vehicle with wheels driven by each individual electric motor is prospective for efficient driving and mobility on rough ground due to the controllability of electric motors. Experiment and numerical simulation with an electric model multiaxle vehicle are conduced in order to clarify traveling characteristics and discuss a method of controlling electric motors. The model multiaxle vehicle is designed to drive with eight controllable motors for each wheel by two ways of control methods, speed control and torque control. Traveling characteristics of the model vehicle was clarified under two control methods, and suitable control system for electric vehicles was discussed.

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A method of optimal wheel torque and steering angle determination for electric motor vehicles is presented. Electric motor vehicles are increasing with the rise of public interest in the environmental protection. In the case of vehicles driven by controllable motors on each individual wheel, the determination of the wheel torque is an essential factor for efficient drive. In this research, a method of optimal torque and steering angle determination has been formulated by using the variational principle to minimize frictional work done by the tires with the ground contact. Optimal torque and steering angle on each wheel for a four-wheel vehicle was numerically obtained by solving the equations under several driving conditions. The result of the numerical simulation is useful as a guide to control the motor torque of electric vehicles for efficient driving.

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The structure of living things seems to be optimized so that they can adapt to the environment. Especially the research on the dragonfly wing has possibilities to give a suggestion for making lightweight and high rigid engineering structures. The purpose of this research is to investigate the structure of dragonfly wing from the viewpoint of structural dynamics with the pursuit of smart engineering applications. We perform detailed observation of wing structure and dynamical properties by microscope and vibration test. Finally we make an appropriate FEM model.

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Rhonrad is a gymnastic tool that is interesting in terms of dynamics and control. Prom the governing basic equations of a Rhonrad with a fixed gymnast mass, we analyzed the fundamental characteristic of a steady Spiral motion of Rhonrad. First, we obtained the condition for a steady Spiral motion. By examining the eigenvalues of the perturbed motion of the Rhonrad from a steady motion, we next obtained a stable region of Spiral motion against a small disturbance, and discussed a common rule of gymnast for a stable Spiral motion. We further analyzed a feasible region of the stable Spiral motion without slipage for a limited frictional coefficient.

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To achieve high-efficiency biped walking, we proposed a self-excited walking of biped mechanism and clarified the characteristics of the self-excited walking whose supporting leg's knee is straight and bending by the simulations and experiments. This paper presents walking characteristics of a self-exciting biped mechanism whose stance leg's knee is bending, focusing on the combination effect of the bent knee angle and configuration of feet and upper body mass. We examined the walking characteristics for a biped model whose upper body mass is attached to the front position of the hip. As a result, we found that the walking period decrease and the walking velocity can increase greatly by shifting the additional mass only slightly.

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This paper presents an active biped robot based on passive dynamic walking. In the first part of this paper, a Passive Dynamic Walker that achieves 3-D biped walking along a shallow down slope was presented. We then showed an active biped robot which can walk straight on a level ground. Through the experiment of passive dynamic walking, it was shown that the foot form of the robot might be considerably important for smooth walking. Because the foot form has great influence on the shape of the potential field between the center of the gravity of the robot and the ground, the gradient of the potential field was utilized to walk by actuating a part of mass for locomotion of the center of the gravity. As a result, smooth biped walking on a level ground was realized according to this mechanism.

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In this research, flexible structure is used as robot's foot to improve the running motion. At first in this paper we give the model equation of flexible structure, and analyze the flexible foot using computing tools such as DADS, ANSYS and MATLAB. Next, to realize the goal motion pattern motion, we unproved the VCC (Variable Constraint Control) to control the runbot with flexible foot. By simulating the hopping motion in computer, we proved this control method is effective. The result of simulation is showed at last in this paper.

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In late years, Several types of running or walking robots have already been studied and developed. However, there is no robot which runns with spine joints. Our Runbot Project team has already created a robot 'Runbot2C' which succeeded walking motion and running motion in three dimentional plane using a piece of robot Therefore, we have .developed a new running skill for 'Runbot2C' using spine joints.ln this skill, we just use simple PD control.

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Recently, the concept of realizing product needs the high level creativity of the rapid application for demanding the changes and the varieties of the value. It is demanded to ascertain the true characteristic of the desirable structure with a big fault of the process which finds the structure of the high originality from the function design. CAE technology is usually used in many cases in the structure design process. But, there are a few CAE tools using to create the high originality structure design from the function design. This paper is described "the high originality structure design" for the creative design tool. The visualizing CAE simulation results and many kinds of visual thinkings support the more creative

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In order to improve noise and vibration of industrial sewing machine, modal analysis and frequency response analysis were performed. More than 10 modes are obtained below 3000Hz, and some modes are relative to . vibration of an oil-pan. According to frequency response analysis results, the oil-pans local frequency mode may have strong affection to the noise and vibration. Finally design optimization was performed and obtained the direction of the effective shape modification.

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In this paper, we introduce a new approach to surface mesh improvement problem. In contrast to previous methods we do not tend to preserve new mesh vertices on the original discrete surface. Instead our technique keeps mesh nodes very close to a smooth or piecewise-smooth surface approximated by an initial mesh. As a result, the algorithm is able to improve mesh quality while preserving essential surface characteristics and features. Proposed approach can be applied iteratively not only to polygonal meshes but also to 2D and 3D curves that allows to treat sharp edges and surface boundaries. We demonstrate effectiveness of our method using various triangular and quadrilateral meshes..

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In these years, various types of machines have advanced to be more high-performance, light and small. On the other hand, it becomes hard to achieve a required performance of the systems only by structural design. It has been expected that technology of smart structure will contribute to the development of small and light-weight mechatronics devices with the required performance. In this study, the smart pantograph mechanism installed in a precise positioning device is composed of the PZT sensor and actuator in order to reduce the structural vibration. The placement of the PZT actuator and H_2 control system are simultaneously designed based on genetic algorithm to improve the effect on the vibration suppression. It has been verified by applications that an enhanced performance for the vibration suppression can be achieved by the proposed integrated design method.

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CAE technology is indispensable to present design & development in every industries. But because it is the main purpose that the CAE tools are used for grasp the phenomenon, it owes a good deal to expert engineers that in order to do the better design. In this context, optimization tools have started to get a lot of publicity as the ways to improve the situations. The optimization tools are used for not only finding the optimal solutions but also improve the system of design & development of its own. This report shows some examples using the general-purpose optimization tool in Fluid dynamics, Structure dynamics, Control regulation and so on.

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The synthesis process from the function design to structure design is most important for such new creative development. It is effective to combine the graphical design process, the function designs process and also the structure design process, based on a development concept. The usual prediction technology by forward CAE is poor at a creative process. "Visual Thinking", to help the imagination to new structure/design, and "Thinking CAE", to grasp the essence of new developed structure, are key technology. The construction of the digital engineering environment to digitalize directly the visual information of new image, as virtual reality, becomes needed.

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Strategy of multidisciplinary optimization for laser-driven micro-airplane is demonstrated in this study. The laser propulsion is significantly effective to achieve the miniaturization and lightening o of the micro-airplane. The laser-driven micro-airplane has been studied with a paper-craft airplane and YAG laser, resulting in a successful glide of the airplane. The integrated laser propulsion/tracking system has been developed to achieve an actual flight and control of the laser-driven micro-airplane. It is expected that the performance on propulsion and control is effectively improved by the multidisciplinary optimization of structural/fluid dynamics and control system. In this paper, the optimizations of the wing shape, the propulsion mechanism and the smart structure used as wing have been conducted to enhance the performance of the laser-driven micro-airplane.

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For the vehicle interior noise, muddle sound should be reduced. To reduce the noise, new honeycomb can be used. In this paper, in order to reduce the interior noise by new honeycomb structure, firstly the honeycomb structure is designed and optimized. Secondly frequency response analysis of the interior noise is performed. It is found that the resonant frequency of the indoor air is lowered. Finite element method is used to analyze the interior noise reduction.

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In this paper the reduction analysis of the so-called 'booming noise', which occurs due to the resonance of vehicle cabin, is tried to carry out by using finite element method. For the reduction method a Helmholtz resonator, which is well known in the field of acoustics, is attached to a vehicle cabin. The resonance frequency of a Helmholtz resonator can be varied by adjusting the length of its throat. Therefore the resonance frequency of the resonator can be considered to follow the acoustical characteristics of the cabin by using an Origami structure. The simply shaped Helmholtz resonator is set up to the back of the cabin according to the resonance frequency of the cabin and the frequency response of the sound pressure at a driver's ear position is calculated by using finite element method. It is confirmed that the acoustical characteristics of the cabin is changed largely by attaching the resonator and the sound quality is quite varied. In future the analysis by using an Origami structure Helmholtz resonator should be performed.

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