A new optimization method for the design of axial turbine stages is described, which can search for the global optimum solution and realize the robust design. In order to realize high efficiency in turbines, it is necessary not only to apply the latest technology to turbine apparatus, but also to optimize various design factors using conventional technology for the purpose of cost effectiveness. The feature of the new method include creating orthogonal arrays, changing the level values of design factors, and evaluating standard deviation of the objective function for every search step. The orthogonal array is selected based on the number of factors & levels, and the level values are changed based on the trend of the optimum solution. As a result of applying the method to the optimum design of turbine stages, it is shown that the method can search the global optimum solution and the tolerances of design factors greatly affect the robustness of turbine efficiency.

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A suspension of a vehicle is the support system between a vehicle body and wheels. The task of a suspension is to support the vehicle body and develop ride comfort. But if the attenuation force becomes large, the passenger will feel hard at high frequencies. If the attenuation force becomes small, the passenger will feel soft at low frequencies. If the coefficient of spring becomes low the vehicle's natural frequency of vibration becomes low, thus the heave, rolling and pitching will become large. In this study, a fuzzy sliding mode controller for real vehicle has been designed. Experiment results are presented to confirm effectiveness of this new algorithm

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This paper presents driver models for a vehicle avoidance maneuver in cornering. The models are based on a preview driver model which has either a compensation control or a pursuit control. The preview point is detected by a variation of the present radius which is equivalent to a third-order prediction model, including a centrifugal jerk. The unknown control gains in the models are determined by an optimization program based on a Legendre pseudospectral method. A second-order prediction model, commonly used in cornering analysis, is compared to numerical examples. For the compensation model, the Proportional-Integral (PI) control results in a steering angle with two distinct behavior clearly : 1) steady-state cornering due to the Integral (I) control and 2) transient response due to the Proportional (P) control. The pursuit control has a sufficient response when the steering angle for the steady-state cornering is provided via feed-forward control, even if the P control is used for the compensator.

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It is well known that asymmetric vane spacing can result in decreased levels of the excitation at specific frequencies. In this paper, the resonant response reduction of turbine blades due to asymmetric vane specing is studied theoretically for the most probable asymmetric vane in which the vane count of the upper and lower half is slightly different. First, a method for predicting the vibratory stress of the blade for the asymmetric spacing vane is proposed including the effect of the multi-resonance due to the excitation force clustered around the harmonic corresponding to the number of the vane count. Secondly, a parametric study is carried out to clarify the influence of the multi-resonance on the blade resonant response reduction for typical shrouded blades of steam turbines. Experiments are also carried out to verify the effect of asymmetric vane spacing on resonant response reduction using a turbine blade of turbocharger. From these results, it is concluded that asymmetric vane spacing is very effective for reduction of resonant stresses of a shrouded blade of steam turbine.

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This paper deals with the occurrence mechanism of the squeal phenomena generated in a new type of bicycle disk brake unit and its countermeasure experimentally and analytically. It was made clear that squeal was in-plane vibration in the direction of disk surface with frequency 650 Hz caused by frictional characteristics with negative slope with respect to the relative velocity, and was generated in the vibration system including brake unit and spokes, in the same manner of old type of disk brake unit. The countermeasure against squeal by using a dynamic absorber was conducted. The simple analytical model of the bicycle disk brake system was set up. Some features of squeal phenomena and the optimal design of dynamic absorber for quenching squeal were made clear analytically and it was confirmed that the analytical results agreed well with the experimental ones.

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Numerical results are presented on chaotic vibrations of a cantilevered beam under vibroimpact. The analytical model consists of a cantilevered beam, subjected to periodic excitation, and a bar that restrains the amplitude of the beam. Equation of the motion of the beam is discretised by the finite element method and impacts of the beam are computed by using the coefficient of restitution rule. Time responses of the beam are calculated with direct integration by the Newmark-β method. Then the responses are inspected with the frequency response curves, the Fourier spectra, the Lyapunov exponents and the principal component analysis. The numerical results are compared with the experimental results that are previously presented by the authors, which verify our numerical results. Effects of the location of the bar and of the clearance between the bar and the beam on the chaotic responses are examined by the numerical results. As the location of the bar becomes farther from the clamped end and the clearance becomes smaller, the frequency region of the impact vibration is enlarged. The chaotic responses of the beam generally have contribution ratio of higher vibration modes less than 5%. However, when the location of the impact is close to a node of a higher mode or super-harmonic resonance of a higher mode is excited, contribution of the higher mode increases up to 10% to 30%.

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The method of normal forms is applied to the nonlinear equations of the liquid motion in a rectangular tank. The basic idea underlying the method of normal forms is the use of local coordinate transformations so that the dynamical system can take the “simplest form”. In this study, the lowest symmetric and asymmetric modes are considered, and two sets of the transformed equations which correspond to the cases with and without internal resonance are derived. The obtained normal forms show that the stationary responses without internal resonance are described by only one state variable. The calculated frequency responses are compared with the results of the direct numerical integrations of the original nonlinear equations of motion. These results show that the response characteristics change from hardening-type to softening-type when the liquid depth is increasing. And it is observed that the time histories of the symmetric mode shift to the negative region. These phenomena coincide with the well-known results.

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The vibration characteristics of the translation motion and inclination motion coupled systems, which is the dynamical models of train, vehicle, and so on, are studied. The nonlinear vibration of such a system subjects to the base periodic displacement is investigated by numerical simulation and theoretical analysis. The occurrence of the auto-parametric resonance at the resonance point of the translational motion is observed when the ratio between the natural frequencies of the inclinational motion and the translational motion is close to 1 : 2. Also, the occurrence of an almost periodic motion is observed when this ratio is slightly different from 1 : 2. The occurrence regions of the auto-parametric resonance and the almost periodic motion are discussed. Besides, the influences of discrepancies of the center of mass which produce slight linear coupling terms between the translational motion and the inclinational motion are investigated. Furthermore, these theoretical results are confirmed by the experiment.

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One degree of freedom model has been used in many problems regarding dynamic analysis for overhead traveling crane. However, various loadings are carried out using a sling rope with increase of workplace. Therefore, crane operation conditions have been expanded in the field work. It is very important of safety and efficiency to operate an overhead traveling crane to suppress load sway. In general, there are two varieties of load sway of overhead traveling crane problem. One is a cart moving, another is after the cart stops. A load sway suppression method to the overhead travelling crane is proposed and discussed. First, in order to analyze the crane traveling motion, a simple two degrees of freedom model considered both of load and hook mass, is proposed. Second, a load sway suppression method is presented. In this method, optimally controlled traveling velocity is available by using the natural period of the crane which gives the minimum energy of the two degrees of freedom model system. The effectiveness of the method is confirmed by a numerical calculation and a model testing.

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In this paper, the engineering evaluation method of the crucian fishing rods is performed. Principal component analysis and multiple regression analysis are performed to the results of the questionnaire about the performance of crucian fishing rods. As a result, the performance evaluation index “stiffness · strength”, “weight”, “top stop” are obtained and the performance evaluation equations of the crucian fishing rods are established. It is cleared that these equations are enough practical in the sight of degree of accuracy. Then, the design of crucian fishing rod is performed by using FE model. The design of the rod with targeted performance is become possible by solving the optimization problem setting the diameter of the rod as the design parameters and the Principal component score as the evaluation function. It is thought that these analysis methods are applied to the tailored design of fishing rod based on the sensory requirement of angler.

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This paper considers vibration suppression of a mechanical transfer system, where the work is connected with the hand flexibly. We adopt the idea of jerk reduction of the hand. From the equation of motion, we first derive a state equation including the jerk and acceleration of the hand, but excluding the displacement and velocity of the work. Then, we design optimal state feedback for a suitable cost function, and show that jerk reduction of the hand is effective for vibration suppression of the work. Since the state feedback including the jerk and acceleration is not practical, we propose a computation method for suboptimal feedback of only displacements and velocities.

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In this paper, it is aimed to model aerodynamic force that acts on the train running at high speed in tunnel sections. An analytical model of the aerodynamic force is developed from the pressure data measured on car-body sides of a test train running at the maximum operation speed. The running simulation of 8-car train subjected to the modelled aerodynamic force shows following results. The simulated car-body vibration corresponds to the practical ones in quality and also in quantity, for the cars connected in the rear of a train. The separation of airflow at the back end of train increases the yawing vibration of the tail car while it gives little effect on the car-body vibration of adjoining car. And, the effect of moving speed of aerodynamic force on the car-body vibration is made clear, that is the simulation with the assumption that the aerodynamic force does not move can enlarge the carbody vibration most remarkably.

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A new concept of improving car behavior in curving by the control of creep force with friction modifier was proposed by the authors. The fundamental experiments were performed by two-roller-rig testing machine to evaluate the creep force characteristics between wheel and rail with or without friction modifier. The other hand, on-board spraying system for friction modifier had been developed by authors and equipped on the service car. And the test results in service line show that the effect of installing the friction modifier into railway system has improved the curving performance. This paper presents results of experiments with scaled model vehicle and theoretical analysis of improved curving performance by the proposed method with friction modifier between wheel and rail with scaled model vehicle.

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The rolling stock test plant at RTRI is used to test railway vehicles by forcefully oscillating its rotating rail wheels in the lateral direction to simulate actual track irregularities. However, the lateral vibration acceleration of car body measured on the test plant is different from that observed when a car runs on actual lines. This phenomenon is conspicuous in particular when the irregularity wavelength is short. It is difficult to predict actual characteristics of vehicle dynamics at high precision, therefore, from the tests to use actual irregularity data as it is. Thus, we numerically determined a weighting function to be applied to the track irregularity data to reproduce the actual car body response characteristics on the test plant and developed a system to oscillate the rail wheels accordingly.

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Conditions of track have conventionally been measured by using exclusive inspection vehicles. If the conditions of the track can be detected by attaching simple sensors such as accelerometers on board of commercial vehicles, more efficient maintenance of tracks would be possible. This paper describes rail corrugation detection from vertical acceleration of a vehicle body and the running noise by time-frequency analysis. An actual vehicle running tests on a commercial line was conducted, in which vertical acceleration of axle boxes and a vehicle body, and exterior noise were measured. In this paper we show first, the rail corrugation can be detected from the vertical acceleration of vehicle body by multi-resolution analysis (MRA) using wavelet transform. Second, it is shown that the incipient corrugation can be detected effectively from the exterior noise measured in actual vehicle, and finally, these methods can be applied to the detection of rail corrugation from interior noise measured in passenger room.

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Severe random vibration is easily induced to satellite structure during the flight. Ground acoustic test is conducted to verify the structural design and abnormal function of equipments. Prediction of the response variance, therefore, can be determined to define the design tolerance in probabilistic sense for achieving the conservative design purposes. This paper is concerned with the vibration response variance of the satellite plate subjected to high frequency diffused acoustic field excitation. Poisson point process theory for occurrence of natural frequency is employed to derive the theoretical model for the statistics of the response. The theoretical model is developed considering the spatial variance caused by modal function of the plate. The finite element modeling of plate and diffused acoustic field is executed to validate the variance value predicted by the theoretical model. The theoretical model is also favorably compared with the acoustic excitation experiment of the satellite panel.

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This paper is concerned with the vibroacoustic response of satellite equipment panel subjected to high frequency diffused acoustic field excitation. Various prediction methods for the response have been developed, namely : (i) mass ratio method, (ii) NASA Lewis method, and (iii) impedance method. The prediction accuracy of those methods, however, is poor for the case where the structure of the equipment is distributed in small area of the panel and can be regarded as a plate. In this paper, the new method dealing with that case in particular is developed considering area impedance coupling between equipment and satellite panel. The acoustic excitation experiments for nine cases of equipment mount are conducted to compare the exiting methods with the new method developed in this paper. The result from the comparison shows that the new method provides a wide flexibility not only for the case of main concern but also for the case of large area equipment where Lewis method may be the best approach for the prediction.

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This paper is concerned with the development of a curved beam element in the analysis of large deformation multibody system dynamics. The absolute nodal coordinate formulation which has been used in the large deformation analysis of multibody systems is generalized to the curved beam element which does not suffer from some of existing numerical problems. Using the position vector gradient coordinates used in the absolute nodal coordinate formulation, the rotation and deformation field within the element can be uniquely defined, and this formulation leads to a constant mass matrix for fully nonlinear dynamics problems. In existing beam elements in this formulation, however, since the elastic forces are defined using the Green-Lagrange strain tensor as a volume element, locking phenomenon associated with the shear and membrane forces leads to erroneously stiffer bending characteristics. In order to avoid this drawback, Hellinger-Reissner variational principle is applied to modify the shear stress distribution, while the assumed strain method is employed to avoid the membrane locking associated with the cross-section deformation. Numerical examples are presented in order to demonstrate the performance of the curved beam formulation developed in this investigation.

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Spatial filter whose importance has been recognized is useful for suppressing modal observation spillover and making reduced-order model of the structures. The authors have proposed a design method of spatial filter of structures. The method is able to get rid of the selected modal amplitudes from measured responses in vibration testing. A small number of sensors are used to design spatial filter that are below number of the modes in target frequency range. In this paper FE-model based filtering methodology is presented. The following is the filter design procedure : a fundamental spatial filter is designed from FE-model of the structure, its experimental model is identified by using experimental modal analysis, and finally, spatial filter corrected by the experimental model is obtained. This paper installs the evaluation of optimal sensor position for establishing spatial filter. The workability of the method is investigated by experimental application to a cantilever beam.

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This paper describes the basic theory for modal decomposition and modal cluster decomposition on two-dimensional frequency domain, based on the two-dimensional Fourier transform of array sensor outputs. At first, the concept of modal cluster decomposition was introduced. Then, an objective function was derived to determine the sensor placement to place each modal cluster on any selected line in two-dimensional frequency domain. As a numerical example, the optimal sensor placement was computed for a simply supported beam in case the number of sensor is two. It is shown that this decomposition is used for suppressing several selected modal amplitudes, or placing each modal cluster on any selected line. Moreover there exists the sensor placement that is used for suppressing multiple modal cluster simultaneously.

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Because of the large scale model of the finite element method in these days, it is required to find the method, which can be applied to the optimal analysis, to minimize the time for estimate of dynamic characteristics when changing the structure. We develop here a new perturbation method with complimentary term which is effective to this purpose. Here we show by both numerical and theoretical analysis that the accuracy of the estimate is greatly improved, including the case of without the lower modes, by using the complimentary vector adjusted to the change of structure and input style, which is obtained by Ma-Hagiwara modal method. We can show the possibility by using the method proposed here to reduce the analysis time drastically when the structure is even much changed on a large scale model.

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A technique for compensating friction in a pneumatic servo system to perform position control is addressed in this paper. In our technique, a friction observer is introduced into the control system in order to cancel the effect of the friction, since it is capable of estimating dynamically varying friction. Prior to its application to the control system, a conventional friction observer is extended for adapting to a pneumatic actuator by taking account of the influence of pressure inside the cylinder chambers on the friction at the seal. The effect of this modification on the estimating accuracy is confirmed experimentally. The modified observer is also incorporated into a pneumatic positioning device based on pressure control, and the control performance on the positioning accuracy is evaluated. In addition, it is demonstrated that the device's control performance is maintained by using both the above observer and a velocity observer, even when neither an accelerometer nor a velocity sensor is used for the construction of the lower cost system.

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We have developed a new type AFM (Atomic force microscopy) for semiconductor wafer testing with coarse-fine movement mechanisms, coarse XY stage and fine xy scanner. XY scanner was used both sample positioning and AFM scanning, A unique birds-beak type z-scanner was designed to be constructed with an optical microscope. Firstly we examined basic characteristics of each positioning mechanisms, 20 mm positioning with coarse-fine control in 0.25 s, 2 nm step moving with xy scanner. Secondary the resolution of the AFM system with 0.3 nm and the frequency response with 1 kHz in AFM operation were measured. Finally as AFM observations, a compact disc surface and bare-Si surface of 0.19 nm Ra were clearly measured. We confirmed the usefulness of the new AFM mechanism.

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Recently, practical use of soft actuators is expected in the field of welfare robot. However, feedback control system for soft actuator has not been realized because appropriate sensor did not exist. Potentiometers or optical encoders which are generally used as displacement sensors have high stiffness and such sensors diminish the compliance of soft actuator. This paper presents fabrication of flexible displacement sensor and FMA (Flexible Microactuator) using this sensor. The flexible displacement sensor was fabricated by depositing conductive paste on the surface of rubber. A paste injection system was utilized to deposit the paste and it realized precise control of thickness, width and pattern of the film. Firstly, an experiment on flat type flexible displacement sensor was carried out to evaluate and improve the sensor. The experimental result showed enough linearity and detecting range. Then Intelligent FMA was fabricated by depositing conductive paste on the surface of FMA. Servo control system for Intelligent FMA was set up and high positioning accuracy was confimed by servo driving experiment.

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In human face-to-face communication, both verbal and nonverbal communication such as nodding and body motions are rhythmically related and mutually synchronized between talkers. This synchrony of embodied rhythms generates the sharing of embodiment in human interaction, which plays an important role in essential human interaction and communication. Further, humans make also body actions which express their intention. These nodding and body actions realize smooth and natural human communication. In this paper, we develop an embodied communication system which is composed of speech-driven embodied entrainment characters InterActors and a force sensor. In this communication system, InterActor makes body actions which express intention of affirmation and negation by force sensor inputs as well as entrained body motions by speech input. The effectiveness of the proposed communication system is demonstrated by sensory evaluations.

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A compact and wearable blood extracting medical device applied for biomimetic medical electronic machine (Bio-MEM) such as a health monitoring system (HMS), was newly developed. This medical device can detect blood sugar level for diabetic patient and inject insulin on a measurement result. This device consists of (1) a microneedle indentation unit using a shape memory alloy (SMA) actuator, (2) a blood extracting unit by restitution rubber, (3) a MOSFET type biosensor by employing Glucose oxidase (GOx) enzyme and (4) a insulin injection unit by restitution rubber. The performances of elements were evaluated as : (2) ability of blood extraction, (3) ability of measure blood sugar level and (4) ability of insulin injection. A blood extracting unit extracted human blood at the flow rate of 0.15.μl/sec. Output voltage depended on a blood sugar level with human blood. An insulin injecting unit drained distilled water at the flow rate of 6.5 μl/sec. By this study, basic of medical device was newly developed.

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It is very important to test the intelligent prosthetic ankle joint in various conditions to ensure the usability of the equipment, however, there are some difficulties to evaluate the performance of the first prototype which is controlled by a bulky system adequately for the inferior mobility of the controlling system. In this paper, a prototype with an intelligent prosthetic ankle joint controlled by a mobile system constructed from a notebook computer and a compact and light control unit was developed to enable testing experiments in various environments. Walking experiments with the prototype was carried out and the usability of the intelligent prosthetic ankle joint was confirmed.

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This paper proposes the method that a hexapod robot is traversed irregular terrain such as the stairs or slopes using the hierarchical decentralized system. A higher subsystem, analizes the stability while walking and instructs lower subsystems, is made to participate in the decentralized system of which a lower subsystem that one leg is controlled object. So the robot was achieved walking that adjusted to an environmental change in cooperated operation between subsystems. A conventional “Zero Moment Point (ZMP)” is a useful criterion of stability, but it does not evaluate the degree of stability. Therefore this paper proposes a “Acceleration Stability Margin”. Amount of acceleration that ZMP is necessary for limit in stability area to move. Then Six-legged Walking Chair Robot achieved walking on irregular terrain that improved a movability while keeping the lowest stability margin by evaluating Acceleration Stability Margin at each environmental change.

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Multiple mobile robot system under decentralized control has become more popular because of advantage of fault tolerance and extensibility. This paper focuses on a planning method for an interactive transportation task by multiple mobile robot system. In this task, task assignment is important to solve interaction among mobile robots. In this paper, we propose the self-generating task assignment algorithm in order to realize efficient sorting task. First, we considered parallelism in transportation task. Second, we defined variable of “Progress” in order to estimate value of tasks which can execute independently and in parallel. Using Progress, robots can select executable parallel task and generate task assignment based on efficiency. We developed multi-robot simulator and multi robot system in order to verify the effectiveness.

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The aim of this research is to establish the quantitative evaluation method for lifting task and to clarify the safety posture and optimal motion. This paper firstly examines the operation from differenet three start-on postures with four items : the maximum compressive force and share force on L5/S1 joint, the energy efficiency index, and the degree of contribution of each joint. As a result it has been shown that the load not only to lumbar vertebra but to knee joint should be emphasized and the pose-C is an appropriate start-on posture in which the knee is flexed almost at right-angled and the upper body is raised. Moreover from the simulation using minimum jerk model we found a proper operation, but the actual operation has earlier timing to extend the lower body than presumed. So not only the criteria on the whole operation or the relative criteria but also the absolute criteria paying attention to a portion like knee joint moment seems necessary to study the optimal lifting motion.

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In this paper, we propose a new algorithm, referred to as the Model-based control algorithm for Anti-Gravity Muscles Assist with Ground Reaction Force feedback, to control a wearable waking support system. In this algorithm, the joint support moment of human is calculated based on the term of the antigravity and the ground reaction force of necessary joint moment of human, which is estimated based on the dynamics of a human approximated model. The algorithm is implemented in a wearable walking support device, referred to as Wearable Walking Helper-II and experimental results illustrate the potential of the proposed system.

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This paper presents a virtual reality enhanced hand rehabilitation support system with symmetric master-slave motion assistant for self-performing rehabilitation therapies. The developed system consists of hand exoskeleton device, which provides individual finger joint motion of disabled persons, and a lateral symmetric master-slave motion assistant system joined with virtual reality (VR) environment. Most of disability caused by CVA (Cerebral Vascular Accident) or bone fracture are hemiplegia and impaired hand is only in one side. Based on the peculiarity of this disability, we adopted a symmetric master-slave motion assistant system in which the impaired hand is driven by the healthy hand in the opposite side. Furthermore, in order to provide a pleasant and motivating training environment, VR environment displaying an enjoyable exercise is introduced. To verify the effectiveness of this system, the clinical trial was executed to one subject. Evaluation result of subject's functional recovery is also presented.

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Tactile ground surface indicators installed on sidewalks help visually impaired people walk safely. However, these indicators could be an extra barrier for people who do not use those indicators. In previous study, we suggest that a functional leg length discrepancy while walking on the indicators is one of the reasons for the extra movements of the lower extremities for young. This study examines the effects of these indicators to the elderly comparing the kinematic and kinetic variables of walking on 1) a path without indicators, 2) a path with normally installed indicators, and 3) a path with recessed indicators. The results suggest that walking on the normally installed indicators causes extra movements of the lower extremities such as increased minimum toe heights during the mid-swing phase by raising entire lower extremities, and functional leg length discrepancy while walking on the indicators is one of the reasons for the extra movements of the lower extremities.

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We propose a video-based system which recognizes objects moved and/or left by human, and contribute for the realization of a ubiquitous environment which finds lost properties and suspicious objects in public areas. One method to identify an object moved by a human action is to trace the object and determine times at which the object is grasped and relieved. In case the sizes of the moved objects are at most similar to the sizes of human bodies and the human movements including those to handle objects occur intermittently, an another method is considered, which detects the starts and ends of the human actions and specifies the positions of objects before and after the movements. We adopt the latter approach. The starts and ends of the actions are detected by subtractions of frames captured from a video camera. A series of frame subtractions is used to distinguish between human movements and object movements. An effective background subtraction is developed to identify more than one moved object and objects going autonomously. The history of object movements is recorded and utilized to know where and when the object has appeared.

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The aim of this study is to examine the relation between recognition on visual motion perception and the display of character strings moving horizontally. The method of this research is to consider the effects of the velocity of character strings moving horizontally on visual motion perception from experimental approach. In this study, the subjective evaluation, the eye movements such as the eye fixation and the pursuit movement are measured as the evaluation indices. The results show following : (1) It is shown that the difference of the velocity of character strings moving horizontally effects the eye movement such as the eye fixation and the pursuit movement on visual motion perception. (2) The characteristic of eye movements such as the eye fixation and the pursuit movement is important in the clarification of visual information processing on visual motion perception. (3) It is shown that the optimal velocity of moving horizontally for the recognition of the character strings is from 5.08 to 8.89 (deg/s), when the display range of characters is from 7.62 to 14.54°. (4) The estimation equations that show the relationship between the eye movement and the velocity of character strings moving horizontally are proposed.

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This paper presents a near-infrared light detection method of colon cancer lesion using a marking-clip, which is applied to laparoscopic surgery. In this method, the near-infrared light backscattering from colon tissue and marking-clip is captured on the abdomen side by an endoscope. In this study, irradiating 700 nm near-infrared light, the visualizing experimentation was demonstrated using a colon phantom. The marking-clip can be imaged as decreasing and increasing intensity regions, i.e. cold spot and hot spot. Monte Carlo simulation was carried out to compare with the experimental results and evaluate the system parameters, e.g. irradiating wavelength. Cold and hot spots could be simulated as an image of marking-clip and their contrasts were related to reflectance of marking-clip and irradiating wavelength. Consequently, cold spot was considered to be visualized due to the non-transparent volume of marking-clip, according to the shield of light scattered by medium and reflecting light on marking-clip. The dynamic range of proposed detection can be enhanced in an irradiating condition of 1000 nm.

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In this paper, we propose an in vitro patient-specific anatomical model of human cerebral artery, a hardware platform for simulating endovascular intervention for making diagnosis and surgical trainings. Proposed vessel model hollowly reproduces 3-dimensional configuration of vascular lumens with elastic membranous configuration as a transparent silicone structure, using fluoroscopic information, which is obtained with CT (Computed Tomography), MRI (Magnetic Resonance Imaging) and other imaging modalities. This vessel model also reproduces the physical characteristics of artery tissue, such as elastic modulus, Poisson's ratio and friction coefficient, within respectively 10% of errors. Consequently, it allows practically simulating procedures, which is accompanied by realistic vascular deformation, realistic feel of operating catheters and realistic behavior of surgical instruments (e.g. slip/stick motion and unwinding motion). Presented vasculature model should provide a helpful platform for interventionalists to make preliminary simulation, for young trainees to practice surgical procedures and for developers to evaluate surgical robots, device and other various medical instruments.

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The natural frequency of the coil spring estimated by the Wahl's formura is generally larger than experimental value. It is considered that this causes the form of end turns of spring. We proposed correction method which estimate the corrected number of whole active turns with considering the number of turns to work as spring in end turns and estimate the natural frequency based on corrected turns. This correcteded natural frequency is in good agreement with experimental value.

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This paper deals with a real-time scheduling system of HMSs (Holonic Manufacturing Systems). A scheduling process based on the utility values have been proposed and applied to the realtime scheduling problems of the HMSs in the previous report. It was shown that the proposed methods generate suitable schedules from the view point of the objective functions of the individual holons in the HMSs. A new real-time scheduling method is proposed, in the paper, to consider both the objective functions of the individual holons and the whole HMSs. In this method, all the pareto optimal combinations of the resource holons and the job holons are generated based on the objective function values of the individual holons. Following this, a most suitable combination is selected from the pareto optimal ones, based on the objective functions of the whole HMSs, such as total make span and total tardiness. It is shown, through case studies, that the proposed method is effective to improve the production schedules from the viewpoint of the objective functions of the whole HMSs in comparison with the previous method.

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This paper proposes a simulation-based approach to the evaluation of a forward and reverse supply chain which includes dismantlers and recyclers as well as manufacturers and distributors. This approach evaluates a supply chain from two viewpoints ; environmental load ; and economical aspect (cost, benefit, and profitability) of every company's business included in the supply chain. To evaluate it, the approach models and simulates the material and money flows between the components (such as companies and consumers) of the supply chain. The simulation reveals : whether each of the companies' businesses is profitable ; how heavy the environmental load is ; whether the capacity of each company or factory is enough ; and how much capacity of a factory is required if it is planned to be built and its capacity has not been determined.

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Composite materials are used for many structures because of its high strength-to-weight ratio and easy formation. Secondary machining processes such as drilling and sawing are required to assemble and join composite materials to other structures. When composite materials are machined, machined surface is sometimes rough and it causes delamination of layers and failure of composite material. In this paper, improvement method of machined surface of composite material during drilling is examined. In this method, ultrasonic vibration is used during drilling. First, this method is examined experimentally. Improvement of machined surface is evaluated by surface roughness. It is concluded that machined surface is improved when ultrasonic vibration is used during drilling. Next, experimental results are examined by an analytical method. Cutting force is modeled as equivalent damping force. Condition of improvement of machined surface is proposed.

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Most of work materials consist of multi phase and poly crystals. Each phase has different material property in multi phase alloys. When multi phase alloy is machined, the difference of material property of each phase affects the cutting mechanism. So in this study, the steel which consists of two phase, namely ferrite and pearlite, is supposed as the work material, and the cutting mechanisms of two phase alloys were studied by using FEM. Firstly, the effects of sequential cutting were analyzed assuming the real machining sequence proceed from roughing to finishing on two phase steel. As a result of the analysis, it was shown that smaller cutting force and large shear angle were realized on the second cutting following the roughing comparing with the first rough cutting. Strain induced both in chip and finished layer was also smaller and the residual stress within finished layer tends to be compression on the case the cutting was conducted on the affected layer generated by the first roughing. Secondly, it was shown that strain distribution within the chip is high at the tool side, and is minimum at inside apart from the free side, not on the free surface, because the strain at the pre-machined layer was accumulated on the free side of the chip.

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This paper investigates the influence of viscosity of oil on flank wear, crater wear and finished surface roughness with minimal quantity lubrication (MQL) system, when changing the kinds of coating films of the hob. Experiments were carried out using a fly tool. As a consequence, the following points were clarified : (1) When using the TIN and (Al, Ti) N coated tools, the flank wear and the crater wear increase with an increase of the viscosity of the oil in the range from 19.1 mm²/s to 30.5 mm²/s in the viscosity grade, after that, it decreases with the oil having high viscosity of 47.6 mm²/s. (2) The surface roughness obtained with the low viscosity of the oil is the smallest in all oils tested at the beginning on cutting, and it showed almost the same value as the theoretical roughness at the end of cutting. (3) From the viewpoints of the primary performance such as the flank wear and the crater wear, and the secondary performance of the oxidation stability, the oil having low viscosity of 19.1 mm²/s is suitable for MQL system in hobbing.

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A thread rolling process is simulated using the three dimensional finite element method (3 D FEM) to investigate the effects of the roller displacement speed, friction coefficient and the roller rotation speed on the deformation behavior of the material. In the simulation, a nickel based heat resistant alloy rod is worked on a 2-roller dies thread rolling machine. Since the plastic deformation of the material in the thread rolling occurs mainly on the material surface, especially at the root of the thread, fine meshes should be used for these portions. The three dimensional deformation of the thread generation could be simulated well by using the presented model. The simulation results that a distorted thread form is due to higher roller displacement speed, and a imperfect thread form is due to lower friction coefficient and a roundish ridge line of threads are due to lower roller rotation speed, show the similar deformation behavior observed in the practical thread rolling.

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Molten metals such as gold, silver and nickel are unable to be jetted through an ordinary nozzle, because it is very hard to melt metals with the high melting points in the small printer, extremely high heat-resistance in nozzle elements are required and high temperature exerts high internal stresses in the nozzle due to thermal expansion. Furthermore, high response of start and stop of printer can not be expected with an ordinary nozzle. The authors have invented a new nozzle which can shoot, with high response, a droplet of molten metal with a high melting point. In this nozzle, a tip of gold wire inserted through an injection pipe is melted by electric-discharge and a molten droplet at the tip of the wire is shot out of a pipe by a gas pulse jet. In this paper, a proto-type of a printer using this type of nozzle is developed and its performance such as droplet size, frequency and accuracy of shoots is shown

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In this paper, we researched the experimental conditions of the method regulated by Japanese Industrial Standard for rotational accuracy of Rolling Bearings. We produced a measuring apparatus based on JIS and measured radial accuracy of angular contact ball bearing in various conditions. The results are summarized as follows : (1) The evaluation method in JIS had large dispersion. (2) The influence of the measuring conditions on radial run-out was very big. It was necessary to unify the measuring conditions in order to evaluate the radial accuracy of rolling bearings.

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The crosshead bearing in large two-stroke diesel engines operates under severe lubrication conditions, because hydrodynamic action is limited by low amplitude, low velocity oscillation under high unidirectional load. The recent trend towards more compact engines with increased output raises the bearing specific load, thereby causing the lubrication severity to increase significantly. Thus it is very important to improve the load carrying capacity of the crosshead bearing. In the present study, experiments using a dynamically loaded bearing test apparatus were carried out to clarify how the oil film characteristics could be improved. The oil film thickness was accurately measured using a laser induced fluorescence (LIF) method. The major results are : (1) A decrease in the clearance ratio is generally effective in enhancing squeeze action on the entirety of the bearing pads. When the clearance ratio becomes too low, however, the ability to form an adequate wedge film is degraded, thereby causing the oil film thickness to decrease ; (2) Even when the bearing has a very low clearance ratio, because incorporating the taper geometry on both sides of the oil-groove promotes wedge action, a significant improvement in the oil film characteristics can be expected ; and (3) The minimum oil film thickness becomes a maximum when using the taper geometry with a subtended length of 5 degrees and a taper angle of 0.1 degree.

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An analyzing method for applying to various types of face gears is proposed. Equations to calculate the profile of the face gear generated by the pinion as a profile on a cylinder are derived, and the tooth surface of the face gear was expressed by a series of profiles on each cylinder with a different radius. The envelope curve was calculated using the element removal method that simulates a metal removal process by a tool. The obtained results as follows : (1) A meshing condition diagram that reveals a whole aspect of meshing of the face gears with consideration of two kinds of interferences and tip pointing caused on the gear flanks is proposed. (2) Face gear pairs can be designed in compact size by an appropriate offset between the pinion and gear shafts. (3) By using a worm-like pinion under an appropriate offset, there is some possibility of designing the high reduction face gear pair.

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