One of the authors previously developed an unconstrained and noninvasive measurement system of heartbeat and respiration using an acoustic sensor enclosed in an air pillow or an air mat. The system measured instantaneous heartbeat and respiration periods by applying Kalman filters and maximum likelihood method to the dynamic models of the heartbeat and respiration signals extracted from the sensor output. To improve the respiration measurement accuracy especially in a weak respiration case, the paper proposes a measurement system taking into account not only the fundamental mode of the heartbeat, but also the harmonic component of the heartbeat and the two side band components of the heartbeat signal modulated by the respiration.

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Recently, electric carts for aged people have spread. In order to improve the safety of electric carts, countermeasure based on characteristics of aged people is expected. In this study, we investigate dynamic response of aged people when the electric cart run off. For this purpose, experimental equipment that simulates running off of an electric cart was manufactured, and dynamic response of driver's body was measured. Then, dynamic response of aged driver was compared with that of young dri ver. Moreover, to investigate the role of the handle, dynamic responses when driver is getting hold of and keeping off the handle are compared.

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Purpose of this study is to develop the probe bicycle to which some sensors for collecting the information about bicycle-pedestrian track were attached. Dual-axis accelerometer for acceleration as impulse response, potentiometer for steering angle, magnetic sensor for cycling speed, dual-axis accelerometer for gradient and two gyro sensors for angular velocity were used. The height of difference in level was estimated from the acceleration as impulse response with multiple regression analysis. The width of track was estimated from the steering angle and cycling speed when the probe bicycle slalomed. The longitudinal and transverse gradients of slope were measured with dual-axis accelerometer and gyro sensors. The accuracy of estimation for width and gradient was had to improve.

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Metal injection molding technique has been developed for fabrication of artificial bones and tooth-root implants, in which hydroxyapatite powders are dispersed uniformly through titanium matrix phase. To gain an insight into the optimal compositional conditions, specimens containing different contents of hydroxyapatite were subjected to the measurements of mechanical properties. Microstructure and compositional analysis of cross-sectional surface were observed under an optical microscope or FE-SEM and EDS, respectively. Biocompatibility of specimens were also examined by culturing the adesive osteoblast.

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In this paper, attitude behavior of boiled eggs rotating on the table is concerned. After introducing a new paper concerning this item, the author tries different approach which admit inclination of the total angular momentum vector from the zenith. A very simple approximate second order equation of gyroscopic motion of spinning tops with small inclination angle including frictional effects is derived. Two eigen-values : nutational and precessional modes are given. It is pointed out that (1) initial rising motion is generated by nutation divergence of radial principal axis due to large radius of curveture near the contact point, (2) at final stage, the nutational mode becomes stable due to smaller curveture radius near the spinning axis, (3) locus of the contact point on the egg shell shows a shape of expanded coil spring which comes from inclination of the angular momentum vector to the zenit axis.

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Reciprocating motion/rotating motion converter has been developed in which the reciprocating motion of the converter itself is converted to the rotating motion with one rotating direction. It is easy for the rotating motion to be utilized, for instance, a rotating generator can be easily operated by it. The converter has two pendulum type rotors connected with a spring. The equations of motion are solved numerically to obtain parameters area of synchronous rotation to the reciprocating motion and the validity of the area is confirmed by the experiment. Design procedure of the converter is also discussed through the result.

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This paper describes the experimental results on the transient vibration of a structure excited by unbalanced rotors. When some rotors run on a base plate, which is free to vibrate horizontally, two modes of synchronization, i.e., in-phase synchronization and out-of-phase synchronization are observed under some operational conditions. In the case of in-phase synchronization, some rotors which rotates higher than critical speed are entrained into critical speed and the base plate vibrates violently. The quasisynchronization are also observed.

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Guide with clearance is often used to constrain the excessive deflection due to vibration or sudden disturbance in the rotary machinery. But the impacting and rubbing can cause serious problems in the machineries. Back up bearing is recently used for reducing the friction as the inner ring can rotate. This paper deals with the rotor-backup bearing system and demonstrates the impact model. The dynamic characteristics, such as forward rub, backward rub and impacting, have been investigated theoretically, experimentally and by simulation. The friction force, exerted during the rubbing between the backup bearing and the rotor, shows very important factor to change the motion from impacting and forward rub to backward rub.

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In recent years, Active Magnetic Bearings (AMBs) characterized by non-contact support have been applied in rotors for industrial use, and research to achieve higher performance is currently underway. The Purpose of this research is to pass the 2nd bending critical speed in the flexible rotor supported by AMBs, and also to reduce the vibration of 3rd bending mode at rated speed (250rps). This paper deals with the results of passing the 2nd bending critical speed during a rotational test utilizing a modal balancing method. As a result of balancing, a reduced unbalance vibration is demonstrated.

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While operating contact rotating systems, a periodic polygonal deformation pattern is formed on the peripheral surface of a roll. Such phenomena is called the pattern formation phenomena. The occurrence mechanism of pattern formation phenomena for some contact rotating systems was clarified by regarding the cause of phenomena as the unstable vibration generated in a time delay system. Linear analysis is sufficiently effective in order to estimate the occurrence region of the unstable vibration. However, most prevention methods using the analysis are those of raising some dumping ratio or avoiding unstable region by changing some system parameters. From the point of view of productivity, these methods are not necessarily effective. In this report, the authors suggest a prevention method of the unstable vibration generated in time-delay system using a dynamic absorber. The Runge-Kutta-Gill method is used to simulate the unstable vibration by adding some adequate nonlinearity. As a example, the 1-degree-of-freedom system with a roll which rotational speed changes broadly is investigated from the numerical computational results.

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To improve the reliability and the thermal efficiency of LP end blades of steam turbine, new standard series of LP end blades have been developed. The new LP end blades are characterized by the ISB (Integral Shroud Blade) structure, where the blades are continuously coupled by blade untwist due to centrifugal force. One of the most important technologies to design the ISB structure with high reliability is the analysis method of resonant stress of the blade. This paper presents the analysis method of the resonant stress of the ISB structure, which is caused by the lower engine order excitation force and the stage interaction force. The measured and calculated resonant stresses are compared to show the validity of the prediction method of the resonant stress.

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Measurement system of fluid reaction force generated on annular pressure seal was developed, and which was applied active magnetic bearings. And from flexibility of measurement circumference by design specifications, this system can measure fluid reaction forces generating on centrifugal impeller. It's necessary for the pump designer to consider dynamic properties of flow inside impeller unit and to predict exactly machine's dynamics under various running conditions. Therefore, an object of this study is to investigate the dynamic behavior of centrifugal impeller through the control of running parameter such as flow rate and excitation form. This paper suggests the importance of not ideal but fault analysis

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This paper treats the vibration control of an overhung rotor system. The optimal regulator theory is applied to decide the control gain suppressing the vibrations of the overhung rotor. Influence of weighting coefficients in the cost function is investigated, and the optimal feedback gains to give the effective vibration suppression performance are provided. Frequency response curves are simulated numerically and the effective vibration suppression performance is shown. For practical use, the simplification of the rotor model for controller design and the application of the Kalman filter are also examined. The numerical results are confirmed by the experiments for an overhung rotor with the active vibration control system.

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The balancing of the rotor system is important when it rotates in the high speed. We investigate the vibration control and presumption of the rotor unbalance of the nonlinear rotor system by using disturbance observer. Firstly, we consider the case of the nonlinear Jeffcott rotor and clarify the validity of this method. Then, we study the case of finite element rotor model with nonlinear spring characteristics at the position of the bearing.

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When designing an Active Magnetic Bearing (AMB) control system, it is necessary to achieve stability suppressing vibration in a high-frequency bending mode (Spill-Over) in the high-frequency area outside the range of the rated speed. We have proposed a method for designing a control system using mode control for a long flexible rotor supported by an AMB, and succeeded in passing the second bending critical speed during a rotational test. This paper deals with the design of a controller for an over-hung rotor. In this design, mode separation control is employed as the control method. The effectiveness is confirmed through numerical simulations.

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When the electric power of an active magnetic bearing (AMB) is shut down during a rotor system rotates in a high speed, the backup bearing is important to support and stop a system in safely. In this paper, we study the effect of the backup bearing on the dynamical characteristics of the rotor system during deceleration through the critical speed. We clarify that there are three kinds of whirling motions when the rotor passes the critical speed, and the determination of the motion which actually occuars depends on the parameters of the backup bearing .

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This paper shows the experimental and theoretical study on the stability of the elastic rotor supported in tilting-pad journal bearings, examining the effects of the bearing support, the preload factor, and the bearing load. With the simple bearing support, the rotor was stable up to higher shaft speed. However, with the fixed bearing support, unstable vibration occurs at 4500 to 6000rpm regardless of preload factor and bearing load. Theoretical stability threshold speeds are about 50% lower than the experimental ones in the case of the fixed bearing support, but they qualitatively agree with the experimental results.

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Bump foil gas journal bearings are hopeful applicants that can support a lightly loaded rotor of high-speed turbo-machinery including a micro gas turbine. The bearing is constructed with a flexible circular top foil supported by a corrugated bump foil and has remarkable rotordynamic characterics due to friction force acting on interating surface of both foils. This study aims at analyzing the stability of a horizontal rotor supported with bump foil bearing numerically.

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If we use water-lubricated bearings for an overhang turbo machine to obtain high efficiency, it is important to assure vibration reliability, because the damping of the bearing placed far side of overhung part becomes very small. To figure out the vibration characteristics of rotors of this type, we conducted vibration tests of a motor mounted rotor. We observed jump phenomenon of vibration amplitude and sub-harmonic vibration on these tests. We considered these phenomena are caused by the gap around magnets of motor, and conducted numerical simulations to verify the assumption. The calculated results agreed well with measured results.

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A very effective method of stability analysis is developed for an anisotropic rotating shaft supported by some unsymmetrical bearings. The rotating shaft is modeled as a lumped mass system with large degrees of freedom. Then, the equation of motion of the system becomes parametrically excited linear system with large degrees of freedom. The stability analysis of this system is very difficult. In the presented method, the reduction model is constructed by using only a few dominant modes. The dominant modes are extracted from the complex eigenmodes derived from constant term of the equation of motion by using the approximate state transition matrix derived by the original model. The stability of the original model can be determined from the reduction model very efficiently and accurately. From the results of numerical computation, it is confirmed that the present method is very effective for the mechanical design but the analysis by using a model with small degrees of freedom is not accurate sufficiently.

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This report describes the interim result of the study about applying the method and process of 'systems thinking' to social problems including impressions ('impression problem'). 'Systems thinking' is one of the methods of problems solving for social systems, and by using this method we surely can understand and explain the behaviors of social systems by the knowledge acquired through analyzing their structures. The author is trying to examine which parts of this method are effective and which are insufficient, through actual experiencees and thinking experiment of solving impression problems. And the author is also trying to find out the know-how for solving the actual impression problems successfully by applying this method, and to arrange them as application guidance in the form of the checklist for solving impression problems.

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The aim of this study is to examine Kansei words to evaluate the impression rated by music. Kansei words may be influenced by gender, age, culture, period, etc. We carried out a questionnaire survey to find new Kansei words for rating music. 530 adjectives were compared with Kansei words that were used in previous studies. The result showed that it was important to use some Kansei words which were not appeared in previous papers.

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This paper describes the evaluation of the visibility, when people watch a vehicles' meter. There are many aspects in vehicles' meters as the element of interior now. Some vehicles' meter has so many decorations that it may not have the required basic function. Therefore we focused on which function is more important for the visibility. It has assumed that driver's behavior is to recognize the meter as the picture first and to review from his memory when people perceive the meter. We have evaluated the visibility of vehicles' meter elements.

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Functions of human body fall with aging and expand individual difference of functions. The influence by aging is seen the increase in reaction time of body. Then, in this experiment, we examine a characteristic of reaction of the information which can be predicted or the information which can't be predicted. As a result, we inquire the optimum displays timing , position, size of dangerous signal, and avoidance characteristic of the people to a dangerous information.

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Elderly people living alone are increasing more and more. The system that discriminates motion of daily life has been required for monitoring them. Though the EMG is generally used for discrimination of motion, there are problems such as the noise from daily life environment and worrying about affixing the electrode. In this study, we proposed to use the shape change of the muscle as the index which estimates the cruris action instead of EMG. Muscular deformation is converted into strain amount by winding the band to cruris of foot. As a result, it was proven that there were high correlation between ankle joint angle and muscular deformation.

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To evaluate the applied force of finger tip from the information of fingernail, the strain distribution of fingers were analyzed by FEM. From the analysis, it is clear that the longitudinal strain and the lateral strain occur on the fingernail at the applied force condition. The three kinds of detectors for the strain on the fingernails were made by using this analytical result. The longitudinal strain detector showed most straight output against force up to 40N. On the other hand, the lateral strain detector and the detector of the horizontal displacement of finger tend to saturate at about 20N.

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To obtain the information about force produced by the hand and the fingers, the thickness and the muscle pressure of forearm were measured. As a result, it has been understood that the information of the force against all fingers are able to be obtained from the thickness change of forearm. On the other hand, it is reveal that the muscle pressur e in the vicinity of the wrist shows strongly the information of the force for all fingars. The forces for each finger were obtained individually from the particular positions of forearm

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Recently in Japan, a number of elderly people who lives alone is going to increasing. The purpose of the present research is to develop monitoring system that prevent accidents by using physiological indices, such as surface electromyogram (sEMG) and heart rate (HR). By using such a system, we can objectively judge whether their motion are normal or unusual.

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Recently, better ride comfort has been requested in various vehicle such as motorcycle, train, and cars. The studies on ride comfort has been reported from 1950s. However, most of them has been taken into account only accelerations. Taking questionnaires are major method for evaluating ride comfort, but these are very subjective and are not accurate because the method rely on the memory of human. In this paper, a method for the evaluating ride comfort by measuring Brain wave(EEG). The measured brain wave are signal processed with ESAM(Emotion Spectrum Analysis Method) and multiple regression analysis. From the result, the prospect of prediction of ride comfort with EEG is presented.

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A non-contact evaluation method for the sliminess of cloth by using optical measurement is proposed. Laser light is irradiated on the cloth to be evaluated, and the diffraction pattern from a fiber structure of cloth is observed with a CCD camera. The diffraction pattern is transformed to a two-dimensional Fourier pattern and finally to a radius-spectrum by a computer. The evaluation value for sliminess is obtained as an inner product value between a radius-spectrum of cloth and the feature spectrum obtained with the principal components of radius-spectrums of sample clothes with different sliminess each other. It is shown that the evaluation values agreed with the results of the sense inspection for the sliminess.

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To exploit the comfortable materials for touching, composite materials that consist of baiodigradable plastics and wood particle, were produced. As a result, it was cleared that the comfortable state for touching was "Harmoniously became familiar with the hand" state. When the composite material was evaluated by this standard, the touching sence hardly change by mixing of powder of wood and biodegradable plastics, however, the touching sence was improved by the form treatment of the composite materials.

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