This research is about a statistical diagnostic method for a structural health monitoring which is applicable to existing structures from the present moment. In this method, structural condition is statistically diagnosed by change of a response surface which is regression model of sensor's outputs. Change of response surface is statistically tested with F-test. In the F-test, a threshold value of normal/troubled condition is simply decided from a theoretical F-probability distribution. Therefore, this diagnostic method only requires data of intact condition and does not require the complicated modeling and information of troubled condition. To confirm the effectiveness of the presented method, health monitoring of jet fan is conducted. Load cells are mounted to a supporting system of the jet fan. Response surface is calculated from vibration data measured by the load cells. As a result, structural condition of the jet fan is successfully diagnosed with the method.

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H_2 controller is designed with the reduced order model of smart pantograph structure which is obtained by finite element and modal analyses. The control force is applied by the piezoelectric film actuator and the feedback signals are detected by the accelerometer in the system. The vibration response is suppressed by modal control. The placement of the piezoelectric actuator and the H_2 control system are simultaneously optimized by using GA to achieve an enhanced vibration control performance. It has been verified by simulations that the enhanced performance for the vibration suppression can be achieved by the present method.

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Vibration suppression is very important to boost the performance of advanced mechatronics devices. 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. The smart structure is composed of the piezoelectric sensor and actuator in order to reduce the structural vibration. The placement of the piezoelectric actuator and H_2 control system are simultaneously optimized based on genetic algorithm to improve the effect on the vibration suppression. It has been verified by applications with an L-shaped beam and a plate-type smart structures that an enhanced performance for the vibration suppression can be achieved by the proposed optimal design method.

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Simultaneous optimization with respect to the structural topology, actuator locations and control parameters of an actively controlled plate structure is investigated in this paper. The system consists of a clamped-free plate, a H_2 controller and four surface-bonded piezoelectric actuators utilized to suppress the bending and torsional vibrations induced by external disturbances. The plate is represented by a rectangular design domain which is discretized by a regular finite element mesh and for each element the thickness ratio is used as a design variable. A nested solving approach is adopted in which Ricatti-based control syntheses are considered as sub processes and nested into the main optimization process using the method of moving asymptotes to optimize the structural topology and actuator locations. To obtain clear and manufacturable topology, the popular techniques in the topology optimization area including penalization, filtering and perimeter restriction are also employed. Numerical example shows that the approach used in this paper can produce systems with clear structural topology and high control performance.

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In the production factories and the construction site, as workers become older and the number of workers decrease, the demand for the automation of physical tasks is strong. Focusing on the automation of plant construction sites, one of the most laborious tasks is positioning pipes, valves, and accessories. Specifically, this work contains operations of lifting the object to be installed via multiple manual winches. TO automate this task, a parallel wire mechanism, that must be using inverse kinematics or a Jacobian matrix, can be applied. However, these methods need information of position and posture of the actuators and the objects before using systems. In this study investigates the feasibility of a power-assisted lifting device that directly detects the applied human force using load sensors, without using inverse kinematics or a Jacobian matrix, and that operates the actuators according to the detected force.

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In a car crash, if relative displacement of thorax of the crew is held in the tolerance, any aftereffect will not be remained. To realize this, the tension of the seat belt must be adjusted in a moment by the feedback control system. Therefore, an active seat belt which applied the shock control method using sliding mode controller is proposed. One of the features is no large power actuator is required because the tension of seat belt is controlled by brake mechanism. Then, the effectiveness is confirmed by the numerical simulation. As the result, the maximum deformation of thorax remained in the tolerance.

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Time delay by image processing exists in the information acquired from a CCD camera. Since the sampling time of image information is longer than that of control, control input delay occurs and the following performance to a target trajectry is not enough. In this paper, in order to improve feedback control performance by using a nonhonomic constraint condition peculiar to a space robot, the technique estimating the present state and the state between sample points from the image information is proposed.

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Recently, the demand for motion simulator used as testing devises has been increasing. For example, driving simulators is important for the observation and grasp of human's operation characteristic under various run conditions, development for vehicles design, and operation support system. When motion simulators are used as testing devices, the motion simulators cannot obtain the reliable experimental data without the running reproduction performance of real motion. Although, hydraulic servo system is often used for the simulators, the hydraulic system has the default that acceleration distortion arises by friction between cylinder and piston under conventional displacement proportional control. In this study, control technique that improvement acceleration tracking performance is proposed, based on dual model matching, for the hydraulic servo system. Then the effectiveness of the technique is verified through simulators.

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This paper proposes a new modeling technique and control system design for a flexible rotor using active magnetic bearings to control its elastic modes. The purpose of research is to pass through critical speeds caused by elastic modes of the rotor in order to obtain a high-speed rotation. To achieve this purpose, it is necessary to control not only motion but also vibration. The new modeling method called as an extended reduced order physical model which simultaneously express motion and vibration of the rotor is used. Furthermore, a new controller combined PID with LQ control to flexible rotor is applied.

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This research aims at a seismic response control method for building structures arranged in parallel. The method for adapting a semi-active control is to use the connected building control one. MR damper as a variable damping device is used. In this research, a control model is created using reduced order physics modeling method. It extends to semi-active control system based on a state feedback system. This paper presents two designing methods for the semi active controller with Genetic Algorithm and LQ control theory. The simulation of a seismic wave input is performed. The simulation result demonstrate the availability and possibility of semi-active control for earthquake.

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The vibration isolation system using negative stiffness realized by active control technique was studied experimentally. An apparatus with two pneumatic actuators was developed. The actuators were used for realizing negative stiffness and for adjusting positive stiffness and damping characteristics, respectively. It was experimentally confirmed that the equalization of the amplitude of negative and positive stiffness enabled the system to have zero-compliance against direct disturbance.

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This paper presents the curving performance of railway vehicles with air suspensions. Air suspensions sometimes cause reduction of wheel load at transition curve, so it is very important to evaluate the performance on transition curve and to control air suspensions properly. In previous study it was found that the air suspensions have non-linear characteristics at low speed and that the performance is influenced by the initial condition, the entrance transition curve condition and so on by computer .simulation and experiments using one-car-modeled test bench. In this study, the new concept devices which have functions to make the link rod of air suspension systems extend or shorten were proposed. The control strategies to compensate the difference of initial condition at the curve entry and prevent the reduction of wheel load at exit transition curve at low speed were also proposed. These proposed control methods were examined by the experiments using one-car-modeled test bench and simulations. As the result, expected performance were obtained so that reduction of wheel load was restraint very much.

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The National Research Institute for Earth Science and Disaster Prevention (NIED) is now conducting for constructing a three-dimensional full-scale earthquake testing facility (E-defense). This facility has 24 actuators to supply enough power to the shaking table, and will be equipped basic controller that is designed by Three Variable Control (TVC) Technique. However the table was designed lighter than the capacity of max weight of test structure, it is supposed to have interaction between the test structure and the shaking table. Therefore, to equip a more highly developed controller, we should understand the property of table-structure coupled system with this basic controller. This study shows a simulation result of the structure-table coupled system with TVC.

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This paper proposes a new vibration control method for multiple tall building structures connected with active controlled bridges. Although the method to control the vibration of multiple tall buildings with a different height and dynamic property has been already established, it is difficult to control these buildings with the same height and dynamic property, because a reaction force is not obtained by each building. To solve this problem, the new method to set the hybrid controlled bridge by different height using supporting structure is introduced. Effectiveness of the proposed method is confirmed by simulation.

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In recent years, the space robot which does various work by the manipulator is researched actively, in order to cope with various problems in an astronaut's activities outboard. Unfortunately, the motion of a space manipulator causes disturbance to the spacecraft, because angular momentum is conserved in space. Since it is impossible to integrate the velocity constraint with respect to time, the system is considered to be a first-order nonholonomic system. In this paper, based on the idea of a multi-body dynamics, motion analysis is done in consideration of conservation laws of angular momentum to build an equation of motion in three dimensions.

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The functional model is a modeling method which defined more clearly than before the function of each part unit and the flow of the energy transmitted in them. In this research, it tries to express movement of two link arm in the two dimensional plane by the functional model. Furthermore, the validity of the control system design in the functional model is examined by building into the model of two link arms.

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In this paper, a motion of a rolling wheel on a elastic rail supported elastically with contact rigidity and slip is discussed. The accurate numerical simulation technique for the interaction between the wheel motion and the rail motion is required because of the difficulty of the experiment in practical systems. This motion analysis also includes the contact problem and the flexible multibody dynamics problem. In the system motion with high speed, the amplitude of lateral vibration of the rail increases comparing with the ordinary speed. We pay attention to the motion of the contact point between the wheel and the rail. The effect of the coupled motions between the rotation and the rail vibration, the elastic contact and the rail vibration and so on are clarified quantitatively.

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Various mechanisms in mechanical systems have rolling contact. It is known that the wavy surface caused by wear, called corrugation, generates and develops due to the rolling contact of two disks under a certain condition. In this paper we focus on fluctuation of slip and contact force between two rolling disks. It is expressed as a restraint condition on the contact point that unilateral contact and the surface shape changes with time due to its wear. Modeling and formulation for such like a problem are proposed. Using the numerical results, we discuss about the characteristics of this closed loop system and the mechanism of corrugation development on the disk surface from a viewpoint of the phase shift between the contact force fluctuation and the worn surface profile.

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In mechanical designs much attention is to be paid to human beings from the standpoint of comfort and safety. Once the dynamic characteristic model of human body is built, the effect of vibration can be evaluated in various conditions. Since the spinal column is the main transfer path of vibration from the sheet, the model has a structure of the spinal column with the head. This paper presents a simplified model of sitting human body with the spinal column. The model is constructed so as to have the smaller number of degrees of freedom (DOFs) than the actual spine. Number of DOFs is determined in order to express the dynamic behavior of human in the frequency range of interest. The model parameters are searched so that the transmissibility of the model get agree well with experimental result. Further application of the model such as the load evaluation inside the spinal column is also examined.

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In motion analysis of vehicles, dynamic behavior of a tire is an important factor. Therefore, many models expressing the dynamic characteristic of a tire have been proposed. They are modeled considering the static characteristic of a tire and express the steady state characteristics with sufficient accuracy. However, It is important to investigate the transitional dynamic characteristic of a tire with sufficient accuracy, because it affects the vehicles motion during especially curving, accelerating or breaking. In this paper, the tire model that can express the static, the steady state and the dynamic characteristics with sufficient accuracy is proposed.

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The purpose of this paper is to discuss about how to model and formulate of the nonstationary vibration of a string with time-varying length using finite elements. The string is hung vertically and excited sinusoidally by a horizontal displacement at its upper end. It is modeled and formulated, using the method of multiple scales with a nonlinear scale. In the case that the string moves with the passage through the resonance, the numerical results using the proposed method is compared with the analytical approximate ones and its validity is confirmed.

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This study uses experimental and computational analysis to investigate the dynamic behavior of a fly line. Fly-casting is one of the most significant issues in fly-fishing. In order to cast a lightweight fly, the weight of a fly line is utilized. Fling speed, the casting process and the loop shape of the line while in flight are important for the proper presentation of flies. Moreover, the shape of a fly line is also important for a long cast or controlled cast. In this paper, the behavior of rod and line is investigated experimentally. And a rod and a line are modeled and calculated in the case of wrist fixed.

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The structural modification prediction is very useful based on FRF. But in case of micro devices, the conventional exciter gives additional constraint and mass loading. First using MEMS like structure, the alternative displacement input can not predict properly is confirmed numerically and experimentally. Then a new micro exciter is so developed as to apply successfully to DVD pickup.

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Vehicle component test of automobile is very important at early design stage to provide in-sight consideration of durability in terms of dynamic strain concentration. Based on the fact that the dynamics of component solely is different from those of system, a new strain sensitivity analysis is proposed to give proper mass addition applied to component, which provides same strain concentration as the system.

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This paper describes improvement of cymbal sound quality. At first we record the cymbal sound in time-domain to research the quality. In frequency-domain, we make a sound of cymbal to reduce the power level of frequency band by using FFT, and return in time-domain by using IFFT. We inspect in the method of paired comparison and choose best sound at the result of the inspection. To make a cymbal which has the good sound quality, analyzed the experimental mode, executed by using FEM and optimized the structure model. At the results, it is possible to link structure analysis and evaluation of sound quality

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Braces on Soundboard of acoustic guitar have an influence on sound quality. Usually, the bracing location depends on guitarmaker skill and feeling. There is no guidelines for designing bracing pattern. This paper describes a relationship between the bracing pattern, braces size and vibrational characteristics of a sound board, analytically. The following results were obtained: (l) Vibration surface area and radiation power of the sound board is larger, when the number of the braces on first string side is more than that on the sixth string side. (2) The distance among the braces have an influence on radiation power of both high note and bass.

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In this research, in order to solve the cause of the impeller for large-sized fan by which the crack entered during actual operation at the joint part of the main board and Blade, vibration and stress analysis using the finite element method were performed. The analysis result showed that the cause of a crack of impeller is for concentration stress to occur in the joint part of the main board and Blade owing to the wave phenomenon of the side board by centrifugal force. Then, the structure optimization by pseudo-inverse method was performed for the purpose of stress reduction. When the design variables were made into the board thickness of an element, design restrictions condition was made into the stress which generates a crack part and repetition calculation was performed, stress was able to be reduced to the target value by calculation of four calculations.

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CAE technology has been improved, and a variety of optimization techniques were introduced into the design of the machine structure. A purpose of the optimization technique is to propose the idea of measuring against the engineering problem. However, it was difficult to propose the efficient measurement in past optimization technique such as sizing optimization about the structural vibration problem. Moreover, there were problems in the formulation of the stiffness of the joint parts and the normalization of sensitivity-value in the sensitivity analysis in the transfer function synthesis method. Therefore, to establish the method efficient for the vibration problem, it is proposed the sensitivity analysis based on the eigenvalue and the eigenvector of the stiffness matrices. It will be expected that the field engineer could utilize this method.

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This paper presents a new development in the experimental method for identifying the set of spatial matrices. That is, to realize the identification of the spatial matrices in sparse matrix form in accordance with consideration of structural connections between measurement points. In the previous method that the authors proposed, spatial matrices are usually identified in full matrix form due to the difficulty of realizing sparse matrix. In this paper, the difficulty is broken through using the simplex method of nonlinear optimization. A simple beam structure is identified in sparse matrix form by the newly developed method and in full matrix form by the previous one. Some static and dynamic prediction analyses are then carried out to compare both methods. That is, to verify the validity and the usefulness of the spatial matrices identified by both methods. The results show some advantages of the new method.

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The dynamic behaviors at connecting part is very important for component synthesis of flexible structure like satellite. Two beam structure is used for accurate modeling at connecting part to approximate by translational and rotational springs. This method is applied to a satellite model and appropriate connecting part is predicted to shift the objective natural frequency.

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The Engine department of the Gas-Den, predecessor of the Hino Motors, Ltd. Was reorganized as the Tokyo Automobile Industries Co. and the Hitachi Aeroplane Co. in 1937 and 1939 respectively. In 1937, the Gas-Den, begun the development work of an unusual titled engine. A realization of the Stratified charge engine was done by Mitsubishi and Toyota at about more than half century later in 1996, the Turbo compound engine was done by Wright Aeronautical Co. in 1952, and the sleeve valve engine was succeed only by the Bristol Aeroplane Co. (includes Napier Co. with same technology) in spite of almost all major aero engine manufacturers tried its development. Although the development project of Gas-Den was broken at last stage of the World War II due to urgent development work of the another high power engine, the concept and the will was great. This paper describes an out line of this unusual engine.

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This paper describes an industrial archaelogical aspect of Japanese Semi Diesel Engine.

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This paper deals with the urban traffic infrastructures developed by two Brunels, Marc Isambard Brunel (1769-1849), and his son Isambard Kingdom Brunel (IKB, 1806-1859). They are admired as the great Victorian engineers in England, especially IKB played leading role in the transport revolution of the 19th century. Marc bored the Thames Tunnel with his son, applying his tunneling techniques patented. IKB designed the Clifton Suspension Bridge, over the River Avon in Bristol. Meanwhile, in March 1833 he was appointed their chief engineer of the Great Western Railway (GWR) and his work began with the line that linked London to Bristol. IKB adopted the broad gauge in the whole GWR lines. He also constructed a network of tunnels, bridges and viaducts for the GWR. He laid down three large steamships to cross the Atlantic. His many works are still in use, which are not only urban traffic infrastructures but also technological heritages in the Victorian age.

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For the purpose of electrification program of Tokaido trunk line from Tokyo to Kohzu, fifty-nine electric locomotives were imported from the UK, USA, Germany and Switzerland. In these locomotives, USA made Class ED10, ED53, EF51 (WH/BLW) and ED11, ED14 (GE) are good results for operation. Fundamental design of domestically made Class EF52 electric locomotives were guided by the Japanese Ministry of Railway and associated with four private electric and rolling stock builders. In this report, 1) Historical background of design to domestically made Class EF52 electric locomotives, 2) Outline of this domestically made electric locomotives are introduced.

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Recenrty, our technical high school students make a new attack on the research of food machinery. For example, the sunny-side up egg machine, the chiaotzu (=gyoza) machine,the tea maker. When we attempt to make a food machine, we can set a definite goal which make a certain food. And also, we can study the method of designing and making automatic machinery. Many of them work on sequence control. This paper describes the educational practices of food machinery in our technical high school

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In our laboratory, manufacture and flight tests of PET bottle rocket in the first semester of 2nd grade have been carrying out as introductive education of fluid engineering. The objective of this paper is to investigate a stall phenomenon arising in the PET bottle rocket at the optimum launching angle, which is calculated computationally. The separated vortex patterns over the PET bottle rocket at the attack incidence range 45 to 70 deg have been visualized by hydrogen bubble method and tungsten halogen lamp in the improved water channel experiment.

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The purpose of this study is to develop a learning material for the diesel engine learning students in technical high schoo1,technology colleges and the engineering faculties of universities. This animation material programmed by the software of Homepage Builder 7 to explain the mechanism of diesel engine and its fuel injection systems. By using this, student can learn the basic knowledge about diesel engine more easily and effectively.

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Fundamental exercise of laser education has been recently popular in practices of Mechanical Engineering of Tokyo University. The Mechanical Engineering has naturally introduced Laser education into the curriculum ever since 2000. One of fundamentals of education is to stimulate and to promote students' interest in studying the mechanical engineering. It considered a device to produce a good pedagogical effect on the students'. The present report is summary of procedures and results in the publish

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A curriculum of Fundamental Engineering Drawing, which serves to support engineering design education, is beginning a series of lecture on spring term of the freshman. In this course, students experiences the "learning of basic skill for drawing" , "drawing of idea for personal article" and "communication through drawing". As a result they are able to acquire "drawing skill for engineering design" using their own abilities.

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Recently, a barrier-free environment has been needed in various fields. The educational improvements for disabled students have been carrying out at a number of higher education institutions. In this study, integrated manufacturing practice to a physically handicapped student was tried through the manufacture of Scotch-yoke mechanism. It was found that a physically handicapped student could gain manufacturing experience, enjoying the progress of this work.

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Recently the change of the environment which surrounds engineering education and engineering education is remarkable. The especially, reduction in school hours in elementary school education and junior high school education in engineering education. The decrease in physics engineering applicant who is represented in the language of science and technology detached room. Various systems such as intern ship, PLB, creation education, promoter education, on-the-job training are examined in other side, and they begin actually. It systematically does not commit these in being respectively active, and in cooperating it clarifying system and discussion by today these education system a situation grasp in a past should be carried out as the previous step.

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The apprenticeship in Japan for typical japan industrial present-states are observed at Wajima-city, Yamanaka-town, Aizu-Wakamatsu city, Kawatsura-town. Old traditional industrial system on the hand craft technology have been said to be destroyed and abandoned off because of its low industrial economical efficiency, however, real present states are contrary different. Traditional hand craft technology based on strict apprenticeship still alive in above mentioned industrial areas to produce excellent lacquer wares, so called japan. Younger peoples who has come hopefully to be become professional workers are willing to obey strict apprenticeship training in the craft shop in the city. Industrial importance of apprenticeship is being emphasized, and educational bureaucracy which so far has denied the apprenticeship on the reason of its old fashioned idea, is strictly criticized to make renaissance in traditional Japanese cultures.

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Impact compression was applied to the strip specimen with line of the circular cut-outs made by PMMA. These holes were consist of a central and added two cut-outs which were varied diameter, d, and distance between the cut-outs, pitch p, on the strip. Elastic dynamic strain ε were. Measured on the minimum section of cut-outs of the specimen and also the strain concentration factors K were obtained. Strain concentration factors K at the central cut-out were decreased with the diameter of added cut-outs were increased. It was considered the interference effect of stress wave. Numerical analysis also showed similar results.

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Recently the compatibility of crash safety and lightweight is one of the most important technical subjects in body design. It is considered that the resistant strength has to reach a balanced level between the energy absorption structures and the deformation control structures for crash safety design. Although the CAE technology has been widely and successfully used to get the characteristic values in the crash safety evaluation, it is necessary to accurately estimate the ultimate strength of the structural member of car in the initial stage of the design for time saving. In this paper, the buckling behavior of the structural member is considered and an analysis method is developed. By assuming the displacement during the buckling and applying Galerkin method, the buckling subjected to combined compression and shear stresses, is obtained.

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This paper is concerned with a compression in the case of equal eccentric at the upper and lower ends of carbon steel square pipes with a circular hole in a short column range, supported by a spherical seats. The opening position shifts in a parallel direction with load. Consideration has been given to the formula which is the combination of the analysis based on the energy method with the experimental result. The measurement results show that the formula is in good agreement with those obtained experimentally for a short column range.

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