We aims to develop a robot that can play against human in curling. In this study, we developed the curling stone throwing robot and the throwing experiment was conducted. When we compared the robot which developed in this study with the robot developed in a precedent study, the improvement of the throw accuracy was able to be confirmed, therefore, it was able to throw a stone in initial velocity constant enough. By the throw experiment using the throw robot, we observed stone position when the robot throw a stone to repeat the same course, Change of the quantity of curl by the difference in initial angular velocity, and Change of the angular velocity of the stone.

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Various patterns of impact forces, impact durations, impact speeds and impact areas were observed in athlete's activities on the sport surfaces. Therefore, the study of shock absorption of the sport surfaces for evaluating the response property against the impact produced by the athlete activities is very important To evaluate these properties, the computer simulation method is very useful because it would be applicable to various conditions of impact, such as various impact area and impact shape. This study proposes the method for construction of Finite Element model to evaluate shock absorption properties in various conditions with multi-impact area and multi-shape contact surface. Parameters of physical property characterizing behavior of sport surface, a loss coefficient and an elastic coefficient in complex stillness model, are calculated from the experiment of steady excitation. We analyze and compare with multi intensity and multi impact area test by using Finite Element model.

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In trail running, runners are required to run on various surface conditions such as slope, gravel and muddy surface, it is important to design shoes for trail running with a view to stability and grip properties on those surfaces. The purpose of this study is to obtain a grip designing guide on muddy surfaces by investigating the kinetic and kinematic data in running on clay surface. 2 runners with different pronation types ran on clay surface simulating a muddy condition and tartan surfaces. Both subjects showed that the slipping distance was significantly larger on the clay surface especially in the forefoot area during propulsion. The effect of tread arrangement on outsole on the grip property was also investigated using five different tread patterns. It was concluded that the tread positioned in a high plantar pressure area or positioned towards the front was effective to improve the grip property.

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vThe purpose of this study is to investigate an applicability of multi-intensity multi-area impact test and the viscoelastic model proposed in previous studies to a long pile synthetic turf. The multi-intensity multi-area impact tests and the parameter identification method of the exponential function type nonlinear Voigt model with impact area were performed to one of the long pile synthetic turf. To identify the parameters of the viscoelastic model, 20 impact trials with different intensity are preformed for each 8 different impact areas. Then the elastic parameters were calculated by least squares method prior to the viscous parameters as the primary identification. After the primary identification, the parameter searching was performed to minimize the relative standard error between the experimental forces and the estimated forces as a secondary identification. Finally, a unique set of parameters including area parameters were identified for 160 trials. Although the identification accuracy of some trials were not so high, the proposed model and the identification method can be applicable to the long pile synthetic turf because the low accuracy trials should be improved by the testing conditions, such as the uniformity of surface conditions.

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In the sprint, the sprinters are required to use starting blocks at the crouch start. Therefore, it is important to clarify the effects of the forces applied to starting block at the block clearance on the sprint start. The purpose of this study is to examine the effects of the forces applied to starting block on the start movements. From starting blocks, a sprinter did three different "starting dash" as is done in a sprint running race (normal), pushing the starting block stronger (more), and pushing a little starting block (less) . The forces applied to the right and left starting block were measured by with the force plates(1kHz). And, the block clearance movement was recorded by Hi-speed camera (250Hz).The results can be summarized as follows. 1: Although the strength pushing the block is varied, impulses applied to the starting block did not change significantly. But it was inferred that the rear leg clearance movement and the block clearance time is related with adjusting the impulses applied to the starting block. 2: It was inferred that strength pushing the starting block affects the start movement as well as applying the force at the first and second step after the block clearance.

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To evaluate the properties of the sports surfaces, friction tests and shock attenuation tests have been generally adopted to determine the horizontal and vertical characteristics, respectively. Although the diagonal impacts are often observed in athletic sports, shock attenuation test treats only the vertical impact test. Therefore we developed a two-dimensional impact test device for examining the two-dimensional cushioning characteristics of sports surfaces in previous study. To produce a simultaneous two-dimensional force against a test specimen, we incorporated a parallelogram linkage in the measuring system. In this study, the various cushioned and non-cushioned impact tests were examined to calculate the FR(Force Reduction) values not only in vertical but also in horizontal impact force. As the results, horizontal shock attenuation characteristic was different from that of the vertical one in terms of initial angles. Additionally, the differences of relationship between the horizontal and the vertical shock attenuation were observed in specimens. This result indicates that HFR should be considered for preventing the injuries and providing the equality in regulation.

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Footwear with high walking efficiency can produce a long distance walking with comfort. As a parameter of walking efficiency, the external mechanical work (W_<ext>) calculated by the movement of the body's center of mass (COM) is focused. The purpose of this research is to obtain a sole designing guide of walking shoes with high efficiency. The effects of walking speed and sole geometry on W<ext>, are investigated through various walking motion analyses. It was confirmed that W_<ext> and the peak values of acceleration (A) and velocity (V) of COM increased with walking speed. Some parameters obtained from motion analyses were found as an important parameter of W_<ext> In order to clarify the effect of sole geometry on W_<ext>, some motion analyses were carried out by using practical shoes with different sole thickness distributions. Therefore it was concluded that both the positive and negative heel gradients could produce the high walking efficiency of two different stance phases.

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The purpose of this study is to investigate the effect of curving sole shoes to walking motion. The subjects were eight female university students (age: 19.3± 1.5 yrs, height: 159.3 ± 2.4cm, weight: 54.2 ± 4.3 kg). They walked about 6 meter on walk course with three kinds shoes and barefoot. The motion is simultaneously recorded by three High speed cameras (125fps) and two force platform. The results are as follows. The angle of ankle joint is decreased curving sole shoes compared with another two shoes. The phase of foot flat time of curving sole shoes is shorter than another. The kick phase became longer, and kick force became larger. The heel contact distance of curving sole shoes became near body. Curving sole shoes produced changes and trends in kinetic and kinematic characteristics that seemed to be advantageously for the walking motion.

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Various functions are requested for designing of sport shoes. Especially grip property is one of the most important functions for both the enhanced performance and injury prevention. Usually high friction produces the high performance, however the excessive friction causes the injuries. Experimental approach has some fatal errors for grip designing. Designing method for shoe sole to control friction based on computer simulation like FEM is required. In this study, we establish computer simulation method considering contact surface. In order to check the validity of this method, simulation results are compared with experimental ones. By using the simulation method, we quantitatively investigate the effects of outer sole structure on grip property.

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The purpose of this study was to quantify the functional role of compressive characteristics of shoes sole parts by combining a finite-truss-element shoes model and the equation of whole-body motion. The equation of the shoes sole deformation was developed by modeling shoes sole as a construction of truss elements with nonlinear spring and damper properties. The shoe sole was divided into five regions; such as fore/mid and lateral/medial parts in addition to heel part of sole. The coefficients of eight points of the sole properties were identified from impact test by using an impact device consisting of accelerometer and arm with impactor. The equation of whole-body motion was derived by modeling the human body as a system of 15-rigid linked segments. Dynamic contributions of the support leg joint torques, which were caused mainly by the elastic property of the shoes sole, to the generation of whole-body CG's acceleration were calculated under two kinds of constant running speed conditions, such as Fast(5m/s) and Slow(4m/s), for heel strikers and fore/mid strikers. The results in this study indicate that 1) vertical ground reaction forces were mainly caused by elastic components of sole force regardless of the foot strike types, 2) the plantar flexion torque about the ankle caused by the force exerted at the forepart of shoes sole contributes to the horizontal acceleration of whole-body CG, and 2) the extensional torque about the knee showed negative contribution to the horizontal acceleration.

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At the landing in court game vibrations with various higher frequencies are excited. The range of the frequencies is entirely different from that in running It was clarified these vibrations produced some resonance in human body and made a bad influence on players' performance. The purpose of this study is an establishment of designing guide for court category shoes to eliminate the above resonance. By using a vibration control system, body vibration was firstly measured under the various input conditions. Through these measurements, the relationship between loading head and human body vibrations was confirmed. Secondary the effects of midsole insertion on human vibration were investigated under the above input condition. Therefore it was concluded that the midsole structure and hardness could control the human vibration to prevent the local body resonance.

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An increase or decrease of the hammer head mechanical energy was caused by an accumulation of the positive or negative handle power which was the product of wire tensile force and handle velocity in the wire length direction. During single support phase a decrease of the wire tensile force was reduced by a fictitious force caused by handle relative pulling acceleration and relative leading velocity to thrower's center of mass (C.M.). Ground reaction force was resulted from maintaining balance with wire tensile force, hammer head centrifugal force, hammer handle coriolis force, and so on under rotational coordinate system. During double support phase handle relative pushing acceleration and relative drawing velocity to thrower's C.M. caused a fictitious force which make balance with the addition of wire tensile force and hammer head rotational force in the wire length direction and with hammer head rotational force in the horizontal direction perpendicular to wire, so that thrower pushed the ground on his/her feet.

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The purpose of this Study was to quantify die contribution of support leg joint torques to the generation of the vertical and horizontal acceleration of whole-body center of gravity (e.g.) of skater during inline-roller skating motion. In order to obtain support leg joint torques during single leg support phase in skating motion, an in-shoe thin pressure sensing device (F-Scan mobile) was used to measure plantar pressure distribution on the in-sole for estimation of roller-blade reaction forces. The pressure data was calibrated with the forces obtained by a force platform. The equation of whole-body motion was derived to quantify the contribution of support leg joint torques to the generation of whole-body cg's accelerations, such as vertical acceleration and horizontal accelerations in die forward and side directions. A subject performed a straight skating motion under constant speed condition. The motion was captured with VIC0N-MX motion capture system, and the ground reaction forces were measured with the force platform. From the results obtained in this study show 1) ankle joint torque was a largest contributor to the generation of whole-body cg's acceleration in the vertical and horizontal directions, 2) knee joint torque contributed to the upward, posterior and left-sideward accelerations, and 3) hip joint torque was small contributor to the accelerations in die vertical and horizontal directions.

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The objective of this study was to clarify the muscle load of pregnant women during walking with musculoskeletal simulation. For this objective, we conducted the experimental walking test using 3D motion analysis system, forceplates and electrodes on erector spinae. A subject put on habiliments for pregnancy mock and we obtained motions of body in non-pregnant and pregnant conditions. The motions of body were input in the musculoskeletal simulation and muscle loads around back were analyzed. From the simulation result, the muscle load in pregnant condition was 193% of the one in non-pregnant condition. On the other hand, the muscle load in pregnant condition was 170% of the one in non-pregnant condition in the experiment We showed the possibility that the muscle load of pregnant women could be analyzed by the musculoskeletal simulation.

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The purpose of this study is to compare the differences of running styles, Rear-foot strike (RFS) and Fore-foot strike (FFS), concerning the parameters of the vertical mathematical model. The grand reaction forces are measured by force platform under two types of running style with various velocities ranged from 2.23 m/s to 3.21 m/s. A unique set of parameters of the model for each trial is computed by nonlinear programming to minimize the sum of the relative standard error of grand reaction force and the relative error of rebound velocity. The differences of the running styles were considered by using results from parameters of multi-degree of freedom model and motion analysis. The results of this study indicate that the FFS needs less energy than that of RFS because of its contact style and the impulse as the internal forces and the horizontal ground reaction force.

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We could treat the shaft as elastic body by swing model proposed by Inoue. As a result, we could consider the influence of shaft vending deformation and torsion deformation during swing. We have investigated the influence of shaft designing parameter with the trajectory of golf ball by using this model. The moving of the head would be as below when reducing the shaft stiffness. The launch angle of club face would be higher and the recurving of head to right side would be increased when ball impact.

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Maximum shot distance is one of the goals of the golf swing. In order to hit a shot of maximum distance, swing linear velocity at the impact of the ball, must be maximal. Since the dynamics of club and arm dominates the overall behavior of the swing, these variables must be clarified for understanding the mechanism to produce the maximum velocity of the club. As a step toward understanding the mechanism, we investigated how non-muscular (e.g. centrifugal and gravity) forces of the each link; generates, absorbs, and transfers mechanical energy in order to produce the maximal velocity. This was accomplished using a mathematical analysis, derived entirely from dynamical equations of a three-dimensional double pendulum with a moving pivot model. We elucidated the role of the internal force for natural golf swing.

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The objective of this study was to construct a finite element (FE) model for estimating the behaviour of a golf club during the swing, and to investigate the influences of swing characteristics on the velocity and orientation of the clubhead at impact, by conducting an FE analysis with varying the swing profile. The swing was represented by inputting the positional coordinate data of the grip and the rotation angles of three axes: the two axes perpendicular to the swing plane and the longitudinal axis of the shaft, which were obtained from an experiment using a golf robot, into the cubic grip model. The simulation results generally matched the experimental results for the swing motion, the behaviour of the shaft during the swing and that of the clubhead at impact. The relationship between the swing profile and the clubhead orientation indicates that the particular orientation of the clubhead may be controlled by varying the swing profile, and that the model and the approach for modelling may have potential to be useful for evaluating the performance of clubs.

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The previous studies indicate that the motion dependent term make significant roles for generating end-point speed of linked segment system, especially, in high-speed swing motions. Furthermore, badminton racket has elastic shaft due mainly to trim its weight. The purposes of this study were to quantify dynamical functional roles of upper joint torques and to evaluate influences of inertial parameters on the roles during badminton smash motion in considering deformation of racket shaft. The deformation of racket shaft was modeled as angular displacements of virtual joint settled between adjacent segments by dividing the shaft into rigid segments. The restoring torques about individual virtual joint axes of the shaft were calculated by assuming rotational spring about each axis of the joints. The upper limb segments and parts of racket were modeled as a system of seven-rigid linked segments, and constraint axes of the elbow, wrist and the virtual joints were modeled with constraint equation in order to consider the anatomical or mechanical degree of freedom at the individual joints. A recurrent equation with respect to the expanded generalized velocity vector, which consists of generalized velocity vector and the time integration of the velocity vector, is derived to calculate the contribution of the joint torque terms, external joint force term, and gravity term to the generation of the expanded generalized velocity vector.

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This paper deals with the dynamic motion analysis using joint torques of snowboarder gliding on the actual snow field. The joint torque is estimated by applying the sensor fusion and the closed-loop inverse dynamics to the information of motion measurement systems. The motion measurement system that consists of inertial and magnetic field sensors measures 3-axis angular velocity, 3-axis acceleration and 3-axis magnetic field. The results indicate the optimal joint torque in gliding of the snowboarder. The measurement experiment was conducted by the snowboarder gliding on the actual snow field. The motion measurement systems were attached to the body segments of snowboarder. The snowboarder conducted periodical carving turn. The results of motion analysis by the joint torque indicated the major motion features of snowboarder gliding on the actual snow field. Therefore, the results can be used to clarify the important joint torques in snowboard turns and to evaluate the skill of snowboarder.

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In gait analysis, which is one useful method for efficient physical rehabilitation, the ground reaction force, the center of pressure, and the body orientation data are measured during walking. In the past, these data were measured by a 3D motion analysis system consisting of high-speed cameras and force plates, which must be installed in the floor. However, a conventional 3D motion analysis system can measure the ground reaction force and the center of pressure just on force plates during a few steps. In addition, the subjects" stride lengths are limited because they have to walk, on the center of the force plate. These problems can be resolved by converting conventional devices into wearable devices. We used a measuring device consisting of portable force plates and motion sensors. We developed a walking analysis system that calculates the ground reaction force, the center of pressure, and the body orientations and measured a walking subject to estimate this system. We simultaneously used a conventional 3D motion analysis system to compare with our development system and showed its validity for measurements of ground reaction force and the center of pressure. Moreover we calculated joint reactions and joint moment of each joint.

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We fabricated triaxial force sensor applicable to non-invasive human lingual motion measurement. The sensor contains two cantilevers for shear force sensing and one beam for pressure sensing. These cantilevers and the beam were buried in the silicone rubber. Their hinges are consisting of piezo-resistive layers in order to detect the force applied on the silicone rubber surface. Water swallowing experiment was conducted and we measured the pressure and shear forces acting on palate. From the experiment, we quantified the ease of consumption of the viscosity-increased water compared to the normal water.

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To evaluate the dynamic behavior of human body at landing, a link model, a musculoskeletal model or multi-degrees-of-freedom model are generally used. In this study, the relation of these models is investigated. The movements of the reference points on the body and the floor reaction force were measured at landing. A four-degrees-of-freedom (4-dof) model is constructed and the parameters are identified such as to reconstruct the measured reaction force. And a four-link (4-link) model is also constructed and the joint forces and the moments are obtained by the inverse dynamics. It was shown that the joint reaction force from the 4-dof model and the vertical component of the joint reaction force from 4-link model agreed well. The joint reaction force from the link model is constructed by the joint forces and the muscle forces, so that the joint reaction force from the M-dof model can evaluate the joint force and the muscle force.

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The aim of this study was to describe, in detail, the trajectory of baseballs pitched under game conditions. In six games of a college baseball league, all balls thrown by the pitchers on each team were recorded by using two video cameras. The trajectories of pitched balls were calculated from the video data by a three-dimensional direct linear transformation method. The initial ball velocity, the variation of trajectories, and arrival position of pitched ball were calculated. The results were as follows. 1) Most pitchers threw types of pitches with two or three clearly different ball trajectories, but some pitchers did not. 2) Batters hit balls only in or near strike zone. When thrown a breaking ball, batters occasionally swung at balls below the strike zone. Batters must rapidly make an exact judge on the ball's trajectory, especially for low balls. 3) For some pitchers, the trajectory of fastballs was correlated with arrival position, which should be considered by batters 4) For some pitchers, the initial ball velocity or the vertical variation of trajectory decreased as the pitch count increased. However, this trend was not observed for pitchers who threw a complete game.

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In the present pinch tasks, participants were asked to maintain target pinch force level for left and right hand of 10% maximal voluntary force (MVF) for 40 seconds. The current amplitudes of left and right pinch force were displayed with visual cursors. In no visual feedback conditions, one or both side of the cursors disappeared 10 seconds after beginning of the task. Results showed that errors of the pinch force increased after disappearance of visual feedback. Also cross-correlation coefficient increased soon after disappearance of visual feedback in only condition that disappear both side of visual feedback.

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Free-throws are essential to basketball game outcomes, but there are no existing methods for training athletes with objective free-throw feedback. This study analyzes free-throws by measuring plantar pressure (PP) distributions during free-throw movements and proposes a new method for developing free-throw feedback using PP-based machine learning. PP data were collected from seven university basketball players who performed 50 free-throws. Most subjects had at least one PP parameter (e.g. maximum pressure, center-of-pressure velocity) that significantly differed between success and failure (p<0.05). Additionally, optimally separating PP parameters were unique to each subject. A trained computer was able to predict free-throw results of three follow-up subjects, alternately using support vector machines and k-nearest neighbors, with average classification rates of 0.69 and 0.63, respectively. These results suggest the possibility of new methods for developing free-throw skills using PP feedback.

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The purpose of this study is to propose an evaluation method for the ease of jumping with a jumping rope and consider the structure of it offering the ease of jumping. The rope jumping motion analyses with various rope were carried out to investigate a quantitative designing guide to ease of jumping. It was found that the hand rotation movement was a significant evaluation guide. The effect of different mass distributions of a jumping rope and the shape of a rotator on the ease of jumping were also investigated. It was shown that the possibility that the foot hangs to the jumping rope could change as the mass distribution of a jumping rope was changed and that the ease of jumping could be controlled by changing the shape of a rotator to a curved one.

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Basic relation between the ski deflection and snow groove curve has been investigated at first. On the base of this knowledge, measurement result on the relation among the snow groove size, ski deflection and contacting pressure has been investigated. In case that snow groove depth is small, pressure concentrates around the boot center area. In case that snow groove depth is large, pressure distributes wider in the long area before and back of the boot center. Although pressure distribution changes remarkably with the snow groove depth, ski deflection does not change so much. The relation between the penetration depth and the pressure has been estimated from the measured ski deflection and the pressure. The study on the relation between the formed pressure distribution by the penetration and the ski deflection with the property of the ski stiffness will be the future subject.

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The purpose of this study is to develop the new system that can predict both the ball-speed and the throwing shoulder injury easily and can simulate pitching motion for the high-speed ball and the prevention against injury efficiently. The subjects were asymptomatic 11 adult baseball players who took part in both MRI and pitching motion analysis, (total 358 trials) We made the database composed of the data of joint angles, findings of MRI and ball-speed. We analyzed the database with principal component analysis and classified the motion patterns into the principal component scores. Then we made the simulation system using principal component score and optimization theory. We could predict the lesion existence and ball-speed with high accuracy. We can make the new pitching motion easily while we operate the parameters of principal component scores referring to the prediction value. We can express the new motion with 3D animations.

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Sports training systems are widely used to improve the overall performance of individuals engaged in various activities. Here, we propose the use of optimized muscle activation signals, hereinafter called OPTIMAS, as a tool for improving the overall sport performance of engaged subjects. In this work we studied the underhand throw of softball player to verify the validity of the proposed training system. At first, we calculate the OPTIMAS for an underhand throw of a softball based on the subject's physical characteristics. Then, the subject practices to improve his skills by comparing his electromyogram (EMG) measured in real time with that of the OPTIMAS waveform produced by the optimization calculation. Here, the subject aims to approach the OPTIMAS waveform. The results of the proposed training system show that the method is of great advantage with a gain that leads to a better performance especially in the early stage of the training term.

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The pole vaulting is a sport involving complex dynamic motion. The aim of pole vaulting for the vaulter is to achieve maximum height. To do so, it is necessary to understand the complex relationship between skills and pole properties, and to master it. The purpose of this paper is to study the influence of factors on the pole vaulting performance such as the joints torque of the vaulter, pole stiffness and length etc. However, it becomes the optimization calculation with many design variables, it takes a large computational cost. Therefore, we need a pole vault simulator with small computational cost advantageous to optimization calculation. In this paper, we proposed a three-dimensional rigid body link model of pole and vaulter system by using Open Dynamics Engine (ODE). ODE is an open source, high performance library for simulating rigid body dynamics. The proposed model's pole characteristics and vaulter's joints torque were optimized by using Genetic Algorithm (GA) so as to achieve maximum height. The result of this research can be utilized in sport engineering to understand optimum skills and to design optimum poles.

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The purpose of this study was to investigate skilled movement and control of beat during play Japanese Drum "Gion-Bayashi". Five subjects participated in this experiment and divided into two groups according to years of experience. They performed drum of "WAKABA" in Gion-Bayashi using the Japanese Drum. The musical score of "WAKABA" was composed of Oo-bachi, Chu-bachi, and Ko-bachi. The motions of participants and sticks were captured MAC 3D system (6-camera, 120Hz). As a result, kinematic chain was observed in the right hand Oo-bachi and Chu-bachi. The variability of stick velocity in right-hand Ko-bachi was larger than that in Chu-bachi and Oo-bachi, although there was not difference between Ko-bachi and Oo-bachi in the variability of preparatory stick height. These results suggest that there are multiple drum style in the right-hand Ko-bachi.

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Recently, we can search an event or a place to enjoy our life through information site using a mobile phone or a tablet pc in everywhere. However, it is difficult to find the event or the place where we want to go using information site if we don't have a clear opinion about events or places because most information sites need the name of place or the genre of event. The user hesitates to go to the event that is recommended by the system if the user does not know the event well or have information about the event. This paper presents a system based on two methods that help a user who selects an event using Internet. One method recommends an event suitable for a user based on some onomatopoeia that expresses the present user's feeling and body condition. Another method estimates the user's feeling and body condition after the user went the event. This study has experimented about the recommendation of event and estimation of feeling after the event to 11 examinee using 22 sets of onomatopoeia generated by the combination of 30 onomatopoeias. The examinees think that the recommended event matches onomatopoeias as the retrieval key and are satisfied with the recommended event of about 80% of 22 sets. In the case of the feelings and body condition of when the user went to the recommended event, 11 examinees are satisfied with the estimation result of about 95% of 22 sets.

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Most of traditional studies on information systems aim at seeking highly satisfactory information in a one-time or small number of uses of a system or service, and never take it into account that the user would feel tired of the same system or service after they have used it many times over. In order to solve this problem, this study has modeled the human nature of being tired of the same thing and enabled the measurement of the degree of such boredom. This paper shows our approaches on several fields, and we discuss how we can construct better information systems for continuous use.

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The present study aimed at quantifying the matching between the physiological response of a car driver and the vehicle motion. Assuming that the performance of a head stabilization mechanism, the vestibulo-collic reflex, affects driving feeling, we recorded the activity of neck muscles that help maintain the head position. Electromyograms (EMGs) were recorded from the sternocleidomastoid muscles (SCM). Vehicle acceleration was recorded with a small accelerometer. Subjects were required to perform straight-line acceleration. The EMG response of a driver's neck muscle depended not only on vehicle acceleration but on its time derivative, jerk. A quantitative analysis showed that the EMG profile can be reproduced by a linear sum of acceleration and jerk. Our analysis indicated that the relationship between the muscle response and the vehicle motion can be characterized by two parameters: the optimal weight for the jerk term and the optimal time lag. The current study proposes a method for characterizing a physiological response of a driver to dynamic vehicle motion.

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In this paper, we focus on social isolation among elderly people to better understand the reality of their lives, and analyze the relationship between the factors behind changes in the family structures of the elderly and their social isolation, and changes in modern communities. We also investigate new forms of communication aimed at improving the quality of life in a longevity society. Methodologically, we propose and examine a basic means to enhance local community networks, based on a scale-free network as a foundation for local community formation. From these considerations, we propose a new networking game for constructing the free-scale network in our daily life. The main idea of this paper is based on the alternate reality game that is a type of play experience to cross and virtual reality as part of the game captures the everyday world.

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Music is one of the strong methods to change human emotion and modify their decision making. We know such affection from our experience of the life and utilize it, for instance commercial music, background music in grocery store and aggressive music in casino or amusement park. However, there are few statistical researches between music and decision making. In this research, we aimed at one of the essences of the music, which strongly affect to the human emotion and decision making. In conclusion, we clarify the effect of music tempo and its mutual correlation to other elements.

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Although the basic meaning of "iyashi" and "healing" is identical, Japanese word " iyashi " has much heavier connotation of biophilia. So the roman transcription of Japanese word was used as an English translation of "iyashi". In the first half of the paper, the concept of Iyashi and its relation to design was reviewed in relation to biophilia and triadic approach to human affects. In the last half of the paper, after the discussions about the dimensional approach to affective phenomena, affective structure of iyashi was analyzed based on questionnaire survey. The result of survey revealed two components in people's concepts of iyashi feelings. These are mood factors and attachment factor. The existence of attachment factor in iyashi attested the importance of primary emotion system approach in unraveling affective phenomena.

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"Iyashi" (we never use "Healing "and "Healed "instead of "Iyashi"and "Iyasareru"respectively)is a term that everyone often hears of in Japan. When people get depressed or feel down, they usually want "Iyashi" so as to gain satisfied or peaceful mind. For the purpose of the engineering application, we have already defined Iyashi as the stimulus that restores peaceful mind from the loneliness or nihility mind. However, the essence of Iyashi has not been clarified. Our target is to clarify the physical and psychological structure of "Iyashi", to generate "Iyashi" by the engineering methods, and to provide "Iyashi" for the people to keep their minds peaceful any time in the contemporary society. In this report, we measure brain waves when it is Iyasareru by Iyashi stimulation in this study and am intended that I evaluate Iyashi objectively by analyzing it. We used ESAM for electroencephalographic analysis. There was the parameter indicating the different change in time Iyasareru as a result of analysis and time when it was Iyasarenai. Therefore the possibility that we could evaluate Iyashi using an electroencephalographic measurement objectively was shown.

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We developed an automatic mesh generation system (FORTUNA) for crash simulation of a car body by using Feature Recognition Technology and Mesh Generation Technology. It creates such mesh as those created by skilled operators in a batch job. All procedures are carried out in full automatic with the feature recognition function, which enables FORTUNA to determine features as if by the human eyes, the mesh generation to suit each feature, and the mesh quality optimization. Applying to a Japanese automobile manufacturer, we had the excellent mesh results that require almost no manual mesh modification. As a result, FORTUNA is evaluated as the operator-friendly system that removes the burden of the menial mesh modification work.

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The warm keeping of the body is very important to enhance the immune response and to maintain our health. It is said that a specific wavelength in the regime of far infrared rays plays a very important role for keeping our health due to the improvement of blood circulation. The characteristic of such wavelength is that its frequency is same as the resonance frequency of human body. So, experiments have been carried out to examine the effect of far infrared rays emitted from e-ion crystal materials composed of several kinds of polar crystal materials on human body through the temperature measurements of palm, leg and chest which are radiated by such infrared rays. Of course, e-ion crystal materials involve the resonance frequency with the same as human body and spectrum emissivity is about 0.94. The operation of e-ion crystal materials may be estimated as follows: when a specific wavelength emitting from e-ion crystal materials is discharged to the skin surface, the molecules such as H_2O which constitutes the skin surface violently vibrates accompanying with the resonance frequency and these vibration energies penetrates into the successive inner skin layers. This mechanism increases the internal energy of the blood and consequently, improves the blood circulation. These facts promote the perspiration from human body and also increase the sensory temperature. So, one can understand that such a radiant heat transfer mechanism is very different from that of thermal heat transfer based on temperature difference and temperature boundary layer.

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In recent years, ageing of the population has been emerged as a social issue in Japan. Therefore, it is important to regain and maintain muscle strength for care prevention. We are researching specified muscle training for efficient strengthening. In the present study, design of a motion path is proposed for the specified muscle training using neural network. For training, the load is applied by using a 2-link arm. By using the proposed method to estimate muscle activity level, it is possible to design a motion path that maximizes the activity of agonist muscles and minimizes the activity of other muscles. EMG signal is measured during a training experiment and the degree of muscular revitalization is evaluated by the amplitude of EMG signal. Finally, the effectiveness of proposed approach is demonstrated through experiments.

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An innovative master-slave system implementing force feedback and motion tracking for a rehabilitation robot is presented in this paper. The system consists of two identical motors with a wired connection, and the two motors are located at the master and slave manipulator sites respectively. The slave motor tracks the motion of the master motor directly driven by a patient. As well, the interaction force produced at the slave site is fed back to the patient. Therefore, the impaired limb driven by the slave motor can imitate the motion of the healthy limb controlling the master motor,and the patient can regulate the control force of the healthy limb properly according to the force sensation. The force sensing and motion tacking are achieved simultaneously with neither force sensors nor sophisticated control algorithms. The system is characterized by simple structure, bidirectional controllability, energy recycling, and force feedback without a force sensor. Theoretical back ground of the proposed system and experimental results on a prototype are demonstrated, and the results appraise the advantages of the system and show the feasibility of the proposed control scheme for an upper limb rehabilitation robot.

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The purpose of this study was to clarify the time course of the stiffness of the hamstrings, range of motion (ROM), stretch tolerance, and isometric peak torque (IPT) of knee flexor after a 5-min static stretching for hamstrings. In 24 participants, static passive torque, representing resistance to stretch, was also measured using an iso-kinetic dynamometer and decreased after stretching on all of experiments. On three different days, dynamic passive torque (DPT) and IPT were measured before and 10, 20 or 30 min after stretching. As a result, ROM and maximal DPT were significantly increased and also IPT was significantly decreased at 10, 20 and 30 min (P< 0.05, respectively) after stretching. Although the stiffness was significantly decreased at 10 and 20 min after stretching (P< 0.05, respectively), this effect recovered within 30 min. These results showed that the retention time of the effect of stretching on stiffness was shorter than the retention time on ROM, stretch tolerance, and IPT.

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Now, an exercise has attention because of an increase in health conscious. But the more exercising population increase, the more number of injured increase. These injured are required for rehabilitation. Then, by departing from an exercise, rehabilitation for athlete is prolonged. So applying a competitive exercise to the rehabilitation, it is expected that injured athlete would return to the competitive field in a short term. The purpose of this study is the development of device that can be prevented reducing the muscle, the joint range of motion and the sense in action athletics by using reproduction of the action of running. The rehabilitation device is designed by using a planar 4-link mechanism and to reproduce the movement of the human leg in the action of the running by the movement of the link. Furthermore, considering the load, by applying force to the foot using springs installed in the planar 4-link mechanism for the muscle rehabilitation, it is investigated that the device would reproduce the reaction force while kicking the ground.

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The purpose of this study was to investigate the effect of barefoot running exercise on the grass on the maximum foot grip force. After the exercise training period, the maximum foot grip force significantly increased.

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There are few studies focused on the various joint loads for NW. Therefore, as for examining having joint load reduction effect or not of the NW, it is with an important element judging the right or wrong of the application to everyday life of the NW for patients with joint disease and young people.The purpose of this study is to compare the joint load (lumbar spine, hip, knee and ankle joints) for NW to ordinary walking (OW) on a level surface and for going up and down hill. Standard 3D inverse dynamics was used to calculate joint force and joint moment in the lower limb joints. On level ground, NW had a load reduction effect on the hip compression and shear force, the knee compression and shear force, ankle shear force. Going up hill, NW had a load reduction effect on the hip compression force and knee shear force, ankle shear force. Going down hill, NW had a load reduction effect on the hip compression and shear force, the knee compression and shear force, ankle shear force.

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Falls in older adults are the serious health problem due to the high medical costs and high mortality rates. In the present study we evaluated the risk factors against falling from the gait parameters and assessed the effect of walking orthosis on walking stability. Seven young and eight elderly walked on a self per-propelled treadmill for five minutes with and without handrail, and knee and hip supporters. Time series of gait parameters such as hip and knee angles, and the displacement of the calvaria were analyzed using stochastic and nonlinear analyses. Significant difference was observed in the hip and knee angle variability between young and elderly groups. The use of Handrail, hip and knee supporters did not improve gait stability in the elderly. Chaotic analysis suggests that gait pattern in the elderly might be a random rather than a chaotic nature.

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The purpose of this study was to analyze the relationship between force and muscle size on foot intrinsic and extrinsic muscles. Cross-sectional areas (CSA) of these muscles were measured by MRI, and maximum foot grip force was measured by specific designed dynamometers, in 12 young healthy participants (6 males, 6 females, age 20.1 ±0.7 yrs). Foot grip force was primarily related to the cross sectional area of plantar intrinsic foot muscle (PIFM CSA, r=0.68l). And the cross sectional area of tibialis posterior (TP CSA) and flexor hallucis longus (FHL CSA) were also significantly correlated with foot grip force (TP, r=0.630; FHL r=0.632). These results demonstrated that the foot grip force was influenced by both of the intrinsic and extrinsic muscles.

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