The turning in the ballroom dancing is analyzed in the mechanical point of view, comparing the left turn and the right turn. Reverse Turn and Natural Turn in Waltz are taken as examples. In the syllabus of ballroom dancing, the both turns are described as just exchanging the terms “right” and “left” each other. However, in fact some different feelings exist in the left and the right turns. This causes mainly come from the couple holding form which is a characteristic of modern ballroom dancing. The movements of dancers during the turns are mechanically analyzed focusing the moving paths of the dancers and the inertia forces in the direction of the partner during the turn. The results show different patterns of movements and forces in the left and the right turns. The parameters affecting the left and right difference are also shown, suggesting improvement ways of the dancers’ movements. The left and right difference caused by the Line of Dance is also explained.

Previous studies have shown that trunk muscle function is important for sports performance and that high trunk muscle function leads to high performance. However, the relationship between the performance level and the trunk momentum during sports performance remains unclear. Therefore, this study aimed to determine the relationship between the performance and trunk momentum. A total of 28 healthy men participated in this study. We measured the required time ten times while performing high knee tasks. In contrast, the trunk momentum was measured based on the average value (root mean square, RMS) of the angular velocity data obtained from the gyroscope installed in the lumbar region. The trunk momentum is LBωX-RMS and LBωY-RMS in the flexion extension and rotation directions, respectively. Statistical analysis was conducted using the Pearson product moment correlation coefficient. Significant positive correlations were detected between the required time in high knee tasks and trunk momentum (LB-RMS) (LBωX-RMS: r=-0.71, p<0.01, LBωY-RMS: r=-0.45, p=0.02). Since a negative correlation was found between the performance level and trunk momentum, we concluded that greater trunk movement is necessary for high performance.

A world-class cross-country ski player was aimed at a men's time race by the classical style at the 5.3 km course in Finland Vuokatti. At that time, high-precision GNSS was attached to the head and video camera was attached to the lumbar region of the player to detect sub-technique used during the time race. As a result of comparing the type and frequency of the motion method presumed from the vertical motion of the parietal region with that of the video camera image, high coincidence ratio, 99.5 % in double poling, 100.7 % in diagonal stride, 86.0 % in herringbone 86.4 % in 1 kick double poling, 98.2 % in total average was obtained. From the results of our study, it was suggested that high-precision GNSS can be used effectively to detect sub-technique of classical style of cross-country ski race.

In this study, we tried to analyze the relationship between golf swing and golf club weight based on cooperative action as the first step to design a club adapted to individual swing. For extracting cooperative action from golf swing, we conducted experiment of acquiring swing data. Subjects were two experienced golfers. In this experiment, subjects swung two clubs that differ the club weight. We measured two experienced golfers’ swings by motion capture system (VICON). We built observance matrix from acquired positional data and we conducted singular value decomposition (SVD) on this observance matrix. By conducting SVD, we extracted cooperative action as some independent modes. Then, we conducted Three-Way ANOVA to main mode. As a result, we reached the following conclusion that we could decompose a swing data to some independent modes.

We analyzed connecting technique between two performances in Flop movement on a pommel horse, based on the experimental data obtained from a motion capture system. Examining the movement of center of gravity during transition from one performance to another, we obtained the following results: (1) In the case of single hand support, it is important to attain dynamic stability of center of gravity by controlling a swinging movement of a right arm as a right wrist being its fixed support point. (2) In the case of double hands support, body bending motion by an advanced shoulder movement in circular direction, and the following reverse body bending motion by a hip is a typical feature. Double hands support motion is important because this successive motion seems to assure the following one hand support movement.

We have investigated one of the fundamental maneuvers on Pommel Horse gymnastics, “Double-Leg Circles.” On our studies, an optical motion-capture system and some devices obtain the motion information of human-wholebody. Based on this information, the inverse-dynamics simulations of the wholebody-musculoskeletal model and the analysis of this simulation can be obtained. In this paper, we showed the correlation between the score of the player’s motion skills from the coaches and the terms about the times of one circle, the joint angle trajectories of 5^th lumber vertebra and 12^th rib vertebra and the ration of double hand support time to one circle time. Also, we evaluated the synchronization level of moving waist and chest by correlation analysis and compared the motion skills of multi-players with the scores from the coaches and correlation analysis.

The support swing on the parallel bars in artistic gymnastics was modelled under the assumptions of an underactuated two-link mechanism, the symmetry of the swing, the controller of a virtual constraint, and a smoothness criterion for determining the constraint. The effect of the tilt angle of the first segment (arm) at the start of the forward swing was examined on various characteristics of the motion. The swing speed was monotonically changed with the tilt angle. The torque-change cost of the shoulder joint, the maximum of the absolute value of the shoulder torque, and the variation of the mechanical energy were minimized at similar values of the tilt angle, where the force vector exerted by the bars on the first segment was roughly parallel to the first segment during the swing.

The purpose of this study was to investigate kinetics of the upper limbs’ joints using an instrumented pole which measures load distribution of axial force exerted by each hand along the pole. Four sets of strain gauges, two of them for measurements of axial loading along the pole and rest of them for bending moments, attached on the pole. The pole was modeled as a series of 11 rigid segments connecting its adjacent segment via virtual joint with rotational spring component. The stiffness of the spring was calculated from the pole deformation measured under loading test. Four male pole vaulters participated in this experiment. A motion capture system was used to measure the 3-D coordinate data of 47 and 24 reflective markers attached to the whole-body and the pole, respectively. The estimated force, calculated from the pole deformation based on static force/moment equilibrium equation, was decomposed into the axial force of each hand according to the ratio in distribution of axial force determined by outputs of the instrumented pole. The results obtained in this study show that the left shoulder and elbow joints exerted large extension torque.

Japanese alpine ski racer has not won the medal in the Olympic Game for over half a century. This study aimed at building a novel ski technique that can improve the results of Japanese alpine ski racer. This paper focused on the angle formed by knee and ski board of ski racer in the turn motion, and clarified a turn technique to shorten the finish time by introducing a 3D motion analysis from 2D video based on 3DCAD model matching. As the result, the knee of top level alpine ski racer turned to the inside direction with respect to the ski board during the turn motion compared to not top level alpine ski racer. In addition, we clarified that this turn technique, which is the internal rotation motion of knee, had correlation with other ski skills, which are joint work and leg lean angle.

Recently, motion analysis systems have been used in various fields such as medical field, entertainment, and sports. There are some types of motion analysis systems that use cameras and force plates, and use inertial sensors, etc., but the common problems are the experiments in the restricted environment and errors caused by muscular contraction. Therefore, it is difficult to analyze the motion of athletes who are in the actual games. Therefore, we propose a novel motion analysis system using a solid model. On this method, 3D motion analysis data can be acquired from a two-dimensional image by using a 3D solid model. As a result, this method allows motion analysis based on general broadcast video, thus motion analysis of athletes in the actual games can be performed. However, the operation time is enormous, because the matching manual work required for converting the two-dimensional image into the three-dimensional motion analysis data is manually performed for each frame of the video image. Therefore, the objective of this research is to automate the matching work to shorten the time for matching work. In this research, we develop a system that automates matching work. As a matching work of alpine ski turn movement, we try to automate matching work by using a discriminator by DNN which is drawing attention in the field of image recognition.

We have measured the 3D course profile of a cross-country ski course at Vuokatti in Finland using a survey-grade real-time kinematic GPS, Trimble R8, which has millimeter-level positioning accuracy. We have also measured the course profile at the same time using three GPS/GNSS receivers, AT-H-02, Physilog4 and Galaxy S5, and compared the positioning accuracy with Trimble R8 as gold standard. The AT-H-02 is a portable post-processing kinematic GNSS receiver especially for sport purpose. The Physilog4 is a portable differential GPS and the Galaxy S5 is a smartphone with built-in assisted GNSS. From the measurement results it was found that only the AT-H-02 can measure the course profile with millimeter-level positioning accuracy as well as the Trimble R8. The Physilog4 and Galaxy S5 have a few-meter positioning accuracy, which is not enough for 3D course profile measurement of cross-country ski race.

There are the friction melting theory and adhesion theory to explain snow friction in Skiing. Comprehending presence or absence of melting water and size of real contact area is important to clarify mechanism of snow friction. In this study, evaluating the real contact area on opaque object is attempted by dielectric properties of snow with comb-shaped electrode. In this paper, dielectric properties of comb-shaped electrode are analyzed by a finite element analysis of electromagnetic field. Preliminary experiment has been conducted with silicone rubber and sodium chloride instead of snow. A comb-shaped electrode and a polarizing microscope are used to measure real contact area in this experiment.

We propose a convenient and easy way for skiers to learn how to execute turns by themselves. It is important for skiers to recognize their own turns while actually skiing. A compact measurement method is effective for this purpose. We used the two inertial sensors and one set of the plantar-pressure sensors. The acceleration components of the inertial sensors were used to log the motion of skis. The plantar-pressure sensors were used to measure plantar-pressure distribution. We analyzed how the feet transmit force to skis with the plantar-pressure distribution. One intermediate skier and one expert skier participated in this experiment. They skied in short turns in six trials totally. According to the results of the experiment, the data of both sensors for intermediate skier's and expert skier's turns were clearly different. Therefore, our proposed measurement method will enable skiers to conveniently recognize their ski-turns on their own.

Previous studies have shown that the pressure center of the foot bottom is minimized by adjusting the elevation angle of footbed in the ski boot to suitable angle for each alpine skier. And the fact makes the record time short.

This study investigates the relationships between footbed angle – the position of the foremost of patella -maximum inner lean angle in the turn motion measured by using ski simulator, and the distribution of the foot-bottom pressure.

Those results indicate that there are some patterns between the suitable footbed angle and the position of the foremost of patella in the athletes, and the pattern can be available as an index which evaluates the suitability of the footbed elevation angle.

To improve alpine ski racer's turn skill, Slap-ski which could be heel-freed has been developed. In Previous report, motions of skier's using both of conventional carving ski and Slap ski are measured by using motion capture. As a result, the skier which brought up the potential of Slap-ski, made extended its ROM of hips and knee joints, and in 1st half term, the direction of pelvis heading toward inside of turns, in case of using Slap-ski, compared with the conventional ski's results. However, it was a result in attempts which are unregulated in running tracks. In this report, to clarify the results of previous report and identify the characteristic of Slap-ski in alpine ski racing, the motions of skier during using both of Slap-ski and conventional ski has been measured in course which is regulated in running track. Furthermore, the results of the experiment have been discussed.

Since carving ski has appeared, the advance of ski gears and operation techniques are remarkable. That is, by angling and deflecting the ski, it is easy to turn with few decelerating elements that draw a narrow trajectory along the deflection curve, so that the ski gears can also be operated and ski techniques has also advanced to make use of the repulsive force of the deflected ski as a driving force. In the alpine competition ski, there is a difference in time due to the difference in the deflection characteristics of the ski. Therefore, by using the experimental method of structural dynamics on the difference of the deflection characteristics between the commercial production skis and the custom-made production skis for Japanese top ski racers.

Many people are recently interested in the effects of yoga and some of top athletes utilize it for their training. There are, however, few studies on the effects of yoga from the viewpoint of improvement of psychological performance for athletes. Therefore, this study conducted yoga programs and interviews about the effects of yoga for university athletes. The purpose of this study was to clarify the effects of yoga on their psychological state by quantitative analysis of their utterances in interviews. The subjects were fifteen male university students belonging to the rugby or baseball club. They were divided according to their sport (rugby and baseball) and the frequency of keywords among their utterances was compared between them. The results of chi-square tests showed that the baseball players used more keywords included in the categories of “Relax” and “Image” than the rugby players. The above results suggest the effectiveness of yoga for athletes and the necessity of yoga programs suitable for each competition trait.

In recent years, prosthesis runners wear various prosthetic foot parts and do training, prosthetic runners need to consider the conditioning of the body and prosthetic limbs. In recent years, it became easier to acquire data using an acceleration sensor or the like, and data could be accumulated on a daily basis. In this study, in this research, for the purpose of collecting data on left and right legs of the prosthetic limb sprinter and training contents etc. over time and quantitatively evaluating the training effect, for one runner, on the back of the waist We installed an accelerometer and studied the relationship between the obtained acceleration waveform and conditioning.

This study proposed the analysis method for verbal data combining self-organizing maps and fuzzy cluster analysis in order to understand athletes’ mental states. The application for visualization of the results of analysis was also developed so that we can share the knowledge of the athletes’ mental states with non-psychological experts. The purpose of this study is to establish the method of psychological assessment using athletes’ verbal data through these process. The subjects of analysis were athletes’ utterances during interviews and their mental states were quantified in the form of vector data based on the utterances. These vector data (“psychological vector”) were mapped into two-dimensional plane (“map”) by means of self-organizing maps. The neurons composed of the map were clustered into ten fields and the seven kinds of the psychological evaluation axes were extracted from there. These results of analysis showed we can understand the mental change of each athlete by focusing on the transition of the psychological vector on the map. The developed application was expected to enable us to understand athletes’ mental states and changes more intuitively by expressing the transition using animation.

In this research, the coupling oar combined shafts of different materials was made, and then the influence on fatigue during rowing of vibration induced by using the coupling oar was evaluated. Initially, vibrations for six types of the coupling oar were analyzed. The tendency of natural frequency due to the rigidity and rubber existence in shaft was observed. The next, subjective evaluation for fatigue by using SD method, and objective evaluation by using a rowing measuring instrument were observed due to change the rowing rates by using a single scull boat. As a result, the necessity of appropriate coｍbine of rubber into inboard side shaft and rigidity of outboard side shaft was suggested.

In the present study, the rule was defined rationally by making clearly the dynamics phenomenon about an overhand pass. An overhand pass in volleyball is important basic skill. However, the difference between overhand pass and catching isn't also defined by a rule book. Then no one tells the difference clearly. There are no ways but a referee judges by the subjectivity. Therefore we advanced a study by the following procedures. At the first, it was described about elastic rebound of a ball and phenomenon of "volley ball" was made clear. At the second, we defined which overhand pass is elastic rebound using Muscle-tendon complex. At the third, it was evaluated by running a motion analysis. As a result, it was recognized that the motion analysis is equal to the motion of an overhand pass. Finally, we defined about overhand pass rationally using above mentioned results.

The physical origin of the force to cause a curling stone to curl or deflect has been a long outstanding and thorny problem in the curling physics. In this paper we propose a new physical mechanism “edge model” producing a lateral force to the motion of a curling stone. It is based on the fact that the running band produces the normal Coulomb friction force but also another drag force because the running band is bounded by two edges of different angles, the inner edge angle being a little bigger than the outer edge angle. The difference produces a larger drag on the rear half running band, which is shown to cause the stone to curl to one side or another. The validity of the mechanism was checked and confirmed in a simple experiment carried out using test running bands with different edge angles on a curling ice sheet.

Movement of a curling stone was studied with high-precision digital image analysis in order to obtain the relationship between a friction coefficient and both the translational and angular velocities, using sequential images taken by the camera located on the ceiling. Calibrations to remove lens aberration were done prior to the experiment. Then the friction coefficients were derived from the decrease of the translational velocity, and analyzed with the angular velocity as a parameter. It was found that the friction coefficients become larger when the translational velocity is smaller.

This paper deals with the optimization of the weight in evaluation function. The evaluation function is expressed by sum of product of the feature values based on stone distribution and each weights. There are two aims in this study. One is optimization of weight for evaluation function, and the other is to determine the appropriateness of each feature value which selected for curling robot. After a several feature values are proposed, supervised learning is performed using the averaged perceptron algorithm. Teacher data is selected delivery parameter that show the "good" results from the game record of digital curling. Learning results showed a high reproducibility with the training set, but showed low reproducibility for testing set. As a result, optimization of weights do not proceed, and determination of the appropriateness of the feature value selection is failure. The results suggest that learning should perform after delivery parameters are classified by purpose such as "take", "draw","freeze".

Curling is one of the winter sports called chess on ice. Athletes are required high level skill and smart strategy. This paper deals with curling phenomenon of rotation stone on the ice. To Understand this phenomenon, polypropylene and Teflon sheet makes low friction environment, and curling stone experiment was carried out. Then curling stone phenomenon was reproduced on force plate instead of ice. According to the experimental conditions, it was concluded that the curling stone phenomenon occurred due to the existence of a water film. From this, we devised the equation of motion of the curling stone on ice based on the water film model and incorporated it into the simulation to reproduce the water film at the bottom of the stone. In this simulation, it was possible to reproduce the condition that the curling stone phenomenon is manifested by changing the state of the water film.

Rotation around the longitudinal axis of the javelin has been suggested to affect flight distance in the javelin throw. However, only one study (Terauds, 1978) has provided data on this possible effect in competition. In the present study, the rotational speed around the longitudinal axis at release was measured in the men’s javelin throw at three collegiate competitions. In 133 throws by 38 throwers for which measurements were available, the relationship between rotational speed around the longitudinal axis and throw distance (competition results) was examined. As a result, it was found that the mean rotational speed around the longitudinal axis was 21.0 ± 4.9 rps, which was comparable to the values reported by Terauds (1978). Also, it was inferred that the rotational speed around the longitudinal axis was not intentionally controlled by the throwers and that it may affect the variability of the javelin’s posture in flight. Furthermore, the rotational speed around the longitudinal axis may be related to the success or failure of the throw.

Recently, a great deal of attention has been paid to measuring technology for track-and-field. With the progression of the technology, the movements of sprinters have been captured and analyzed to improve their performance. It was found out that two complex skills, maximizing the horizontal ground reaction force and not twisting an upper body, required for sprinting faster. There was a lot of analysis proved this theory, but a little research focused on the method how sprinters will master these skills. Previous studies demonstrated that a design of training environment forcing subjects to do specific action would lead to enhancing their performance by adapting their movement to the situation. Therefore, this study developed a tool relieving selfweight and extending flight duration as a training environment that it is difficult to gain the ground reaction force and an upper body easily get twisted. The tool has the function to change the flight duration by exchanging rotary dampers. In addition, the tool has been designed to be easily carried and have enough strength for withstanding the impact during use. The result of this tool’s performance test suggested that the tool would induce the rate of the horizontal ground reaction force during a sprint to increase.

The “turbo-jav” which is used for the javelic throw in the junior Olympic games has many characteristic features in geomety different from a spear, including the presence of tail fins. In order to investigate the aerodynamic characteristics of the turbo-jav, we performed wind tunnel tests at the flow speed up to 25 m/s for various angles of attack to measure the drag force, lift force and pitching moment exerted on the turbo-jav. Using the aerodynamic coeffients obtained, we numerically calculated the flight orbit of the turbo-jav and the variation of the angle of attack, starting from the initial condition obtained at throwing experimens. The flyng distance predicted by the numerical simulation was found to be much shorter than that obtained at the corresponding experiments. Since the amplitude of the oscillation in angle of attack during the flight was much larger in the numerical simulation compared to that in the experiment, we proposed a new model in which the resistant term proportinal to the square of the angular velocity was added to the pitching moment. The simulation result was discussed in relation to the oscillatory behavior of the turbo-jav.

Conventional Hill type muscle models have been widely used in the fields of human movement research because of its some advantages in implementation into numerical calculation procedures. While cyclic or repeat human motion such as gate or bike cycling can be simulated with the Hill type model, quick transient responses are not sufficiently simulated. A new muscle model has been proposed to simulate the non-linear human neuro-muscular behavior with two Maxwell elements. The new model is based on two binding conditions of cross bridges between contractile proteins actin and myosin. In this study viscoelastic measurements were carried out for human biceps-brachii by measuring the force response to with ramp displacement under about 10 % of maximum voluntary contraction. The measurement was performed in perpendicular direction to muscle contraction. A measurement component was pushed into muscle belly of upper arm to detect biceps brachii muscle over the skin. A linear actuator was controlled with microcomputer Arduino for ramp displacement of 5 mm with speed of 60 mm/s. The force response was recorded by a load cell. The results are compared with the numerical calculations.

Motor skill trainings are widely used to augment human performance in various area such as sports, medical or welfare. We have previously proposed a visualization method to integrate significant amounts of information relative to human motion to facilitate convenient visual perception during motor learning. This motor learning system helps subjects acquire developed motor skills by referencing integrated information of optimized motion data using a visualized motor skill map. In the proposed method, a self-organizing map (SOM) is employed to visualize the integrated motion data. This map has an ability to express a difference between a teacher signals and measuring signals, as a distance between trajectories corresponding to various time-series motion data on the map. However, it is difficult to use for training system because drawn teacher trajectories are randomly arranged on the map by original algorithm of SOM. The aim of this study is to establish a novel training system using SOM by modifying its algorithm which is capable of controlling a drawn trajectory to compare between a teacher signals and measuring signals easily. To verify the validity of the proposed training system using modified SOM, we evaluated the difference between teacher and measured signals after proposed training. The results of experiments show that our visual feedback system enabled subjects to close whole teacher motion through trial and error training.

Recently, various exercises have been performed including the participation in citizens' marathon meet in various scenes by a health-oriented surge. On the other hand, aging rate goes ahead through our country, it is inevitable that the senior citizens who deteriorated of the ADL (activity of daily living) increase. In late years, a certain exercise work load index AT (Anaerobic Threshold) comes to be used widely in the field of the exercise physiology. The anaerobic threshold (AT) is defined to be the maximum exercise workload in some range in which can do exercise without onset of the 1st blood lactate accumulation during a gradual incremental workload exercise. AT is generally determined by the lactate threshold (LT) method with a blood lactate sampling or by the ventilation threshold (VT) method with a ventilation expired gas volume measurement. These methods, however, were based on the experimental rule. The purpose of this study is to identify the AT by using the objective technique that does not depend on the experimental rule. Specifically, the inflection point of VE, VCO₂ with a gradual incremental workload exercise for AT determination is identified by the strucchange.

We propose a new device that supports table officials in basketball games with using OpenPose. OpenPose uses deep learning in image recognition, and visualizes human movement by detecting human body, hand, and facial keypoints on a single image. In official games of the basketball, table officials are necessary for the progress of games in addition to referees. Table officials mainly consists of a scorer, an assistant scorer, a timer and a shot clock operator. The proposed device of the table officials can read the information such as a score and individual personal fouls by analyzing gestures of referees. Furthermore, the device can display and record the information. We think that the device can reduce some mistakes of table officials.

In this study, we measured the heart rate and evaluated the mental and physical condition at the time of expressway driving. We proposed a heartbeat measurement system using a condenser microphone to measure heartbeat. A heartbeat of the person driving a car at a freeway was measured using proposed measurement system. In the experiments, Visual Analogue Scale (VAS) was used to evaluate driver’s fatigue, drowsiness, and tension in order to grasp the state of the subject. To take the miss value, signal smoothing was applied to the measured heart beat waveform. Using the result of the signal processing, the evaluation index for evaluating the mental and physical condition, the average value of RRI, HF, LF / HF was obtained. Based on the obtained parameters and the results of VAS, the mental and physical condition of the subjects on the outbound route was evaluated. As a result, it was suggested that drowsiness could be estimated by HF at the time of highway driving, because it was most correlated with drowsiness and HF. There was no consistent correlation with fatigue and tension.

There are many factors that cause fatigue to passengers while riding a car. Among them, vibrations are always present during driving, so it is regarded as one of the main causes. Various products have been developed to reduce vibrations, but the car's seat frame material is still made mainly of iron. Therefore, in this study, changes of the state when changing the seat frame material were evaluated using muscle fatigue parameter, heart rate parameter, etc. in order to reduce fatigue of passengers on board. In the experiments, electromyogram (EMG) and electrocardiogram (ECG) were measured when the subject seated on the seat vibrated using ball-vibrator combined to air compressor. In order to measure the frequency, simultaneous parallel measurement of the acceleration in the front and rear direction of the seat (longitudinal vibration), the lateral direction of the seat (lateral vibration) and the vertical direction of the seat (longitudinal vibration) were also estimated. Furthermore, the subject's MPF (Mean power frequency), the RR interval of the electrocardiogram, and the accelerations of the three axes placed on the seat were analyzed from the data oriented by measurement using biomedical amplifier. In addition, Lorentz plot was performed at the RR interval of electrocardiogram. Both the new seat and the old seat (new seat: sheet using lightweight material. old seat: current seat using iron) showed the same tendency when vibrating in MPF, there was, however, no dominant difference between them in both cases. In the Lorentz plot of the electrocardiogram RR interval, sympathetic nerves dominated when the old seat shifted from non-vibration to vibration, whereas in the new seat the parasympathetic nerve dominated and there was a dominant difference.

Pulse is the beat of the heart transmitted to the wall of the artery such as the wrist. It is thought that the pulse can be observed from the surface of the body and can be used as one of various health condition and physical function evaluation. In recent years, the technology of three - dimensional shape measurement using a depth sensor and high - resolution moving image has advanced and observation of blood flow and measurement of blood flow velocity by a peripheral capillary vessel observation device became possible. Using these techniques, it is possible to quantitatively evaluate the pulse, which is a weak movement on the body surface. Therefore, in this research we quantitatively evaluated the dynamics of the pulse of the wrist by using high resolution moving images and depth data.

Even if it seems reasonable accommodation is necessary,it is difficult to expression of intention in the request of reasonable accommodation from people with developmental disabilities. However, even if it seems that reasonable accommodation is necessary, it is difficult to expression of intention in the request of reasonable accommodation from himself. Within this context, we develop an e-portfolio system including heart rate information, which urge reflection from correspondence process for own request for the purpose of supporting expression of intention in the request of reasonable accommodation. In this paper,We report on subjective accumulation by ICF-CY based icon and trial on daily accumulation of stress factors using objective accumulation by Lorenz plot(LP) at RR intervals using wearable terminal.

The estimated population of people of the lifestyle disease in Japan increasing year by year, and it is said that about 70% of the people are lifestyle diseases now. Amount of daily physical activity is strongly associated with the prevalence of lifestyle disease, and thus maintaining certain revel of physical activity is recommended. Short-duration exercise, mainly walking lasting less than 3 minutes, has been reported to account for over 90% of the daily energy expenditure of healthy adults. However, the estimation formula of energy consumption by the commonly used ACSM metabolic equation can be applied only to the steady motion of 5 minutes or more. Suzuki and colleagues propose a new estimation formula for establishing a method of estimating oxygen consumption of short time exercise, but the evaluation of descending walking is insufficient. Therefore, walking experiments were carried out on 10 healthy people aged 18 to 20 years with a total of 15 conditions using a treadmill and stairs. The oxygen consumption in during exercise and post-exercise was measured using a portable gas analyzer in breath-by-breath mode. The root mean square (RMS) of estimate equations was calculated using Leave-one-out cross validation. The RMS (3.49~ 4.08 ml / kg / min) was close to the metabolism at Sitting rest state (3.5 ml / kg / min). But, with respect to the staircase, the results of the Bland-Altman plot analysis showed a proportional error and some correlation it was confirmed that there was. I review an estimated expression, and it will be necessary to get rid of a proportion error in future.

It is known that a phenomenon in which a cardiac rhythm synchronizes with a locomotor rhythm occurs during running. At this synchronization, the cardiac rhythm rate increases in proportion to the locomotor rhythm intensity, and when it approaches the limit locomotor rhythm intensity, an unstable phenomenon of the cardiac rhythm increases becomes sometimes observed. This instability of the cardiac rhythm causes lower exercise efficiency, so it is necessary to keep the stable cardiac rhythm up to the faster locomotor rhythm as far as possible. Therefore, we obtain a model with a locomotor rhythm added to the FitzHugh-Nagumo equation that expresses the cardiac rhythm, and propose a method of a central command to suppress the instability of the cardiac rhythm for this model. By simulation, we show the central command to suppress this instability.

In this research, we aim to evaluate the cushioning property of long pile synthetic turf by modelling and computer simulation. Experimental equipment was developed for multi-intensity and multi-area impact tests with various drop weight ranged from 5 kg to 60 kg. And impact tests with drop height ranged from 15 mm to 75 mm, four different impact areas and 60 kg drop weight were performed to three specimens which have different hardness controlled by the ratio of infill sand and rubber chip. Additionally, we adopted the rounded bottom impact test foot for improving the identification accuracy of the model by reducing the data variation in the same condition. From the experimental results, we proposed an exponential nonlinear Voigt model for representing the dynamic behavior of the long pile synthetic turf and calculated the parameters for each specimen. As a result of identification, the average RSE (relative standard error) of each specimen were about 13% to 15% and it seems that the identification accuracies were relatively high compare to the previous studies. In addition, the buffering performance was evaluated by simulation of various conditions assuming the landing impact during running. As a result, it became clear that the FR values decrease with increasing the impact time in every specimen.

By modelling human posture in quiet standing as an inverted pendulum and its control from the central nervous system as piecewise sampled-data control, we discuss the aging effect to its stability control under seismic acceleration with different intensity. In the model, aging parameters, such as muscular strength, reaction time and sensing errors, are easy to be quantified. We simulated healthy people’s falling down under the acceleration of earthquake according to seismic intensity scale of Japan meteorological agency. The maximum muscular torque at the ankle strongly affects quiet standing posture and 40% its reduction induces frequent falling down. Although degradation of reaction time doesn’t so much influence to the stability control, it becomes important after increasing the error of postural angle.

In a sport to hit the ball, the sense of touch that occurs when hitting the ball is one of the judgment materials for adjusting the hitting movement. Therefore, in this study, we investigated the perceptual characteristics of vibration, which is one of the factors that generate hitting sensation. Since the duration of the vibration generated when hitting varies depending on the hitting point, we considered that the duration of vibration is a factor that changes the hitting sensation, and a hitting experiment was made utilizing deflection of a cantilever. In the hitting experiment, we measured the force that occurs when hitting a cantilever with a stylus, and we investigated the frequency, the duration of the vibration and the impact force generated by the hitting. In addition, we evaluated the intensity of impact from a subjective sensation and examined the influence of the duration of vibration on hitting sensation. As a result, we clarified that a duration of about 30ms is required to recognize vibration as deflection. In addition, we suggested that the vibration with short duration are captured as part of impact and the vibration with long duration are captured as deflections of cantilever. Furthermore, we confirmed that even if the impact force generated by the hitting was comparable, the intensity of the impact was perceived weakness when the vibration recognized as deflection occurred.

The purpose of this study is to clarify relation between atrophy of the brain due to aging and relative displacement between skull and brain by using the physical head-neck model during rotational impact. The physical head-neck model consists of skull part, brain part, neck part and head-neck joint part. The shape of skull and brain part was based on real-shaped three dimensional CAD data and polygon data constructed by CT/MRI images. We constructed two different shaped brain models. One model has the brain shape of young adults reproduced (hereinafter called adult physical head-neck model), and the other is model whose volume is reduced by 10% than it (hereinafter called aging physical head-neck model). The various conditions of rotational impact were given to these models and measured relative displacement between skull and brain occurring in each model. The relative displacement between skull and brain is calculated from the position data of each marker photographed by two high-speed cameras. As the result of that, it was found that the relative displacement between skull and brain is larger in the aging physical head-neck model than in the adult physical head-neck model. Therefore, it was revealed that brain atrophy due to aging increases the relative displacement between skull and brain when rotational impact is applied to the head.

The mechanism of ski sliding still has not been completed clarified. Previous studies have reported that as the sliding speed increases in alpine skiing, the coefficient of kinetic friction between the ski and the snow surface decreases, and the strength of higher order frequencies generated in the ski increases. However, the cross-country ski has not been studied yet and it is unknown what kind of influence the similar high-order vibration frequency has on the running. In this study, by conducting hammering test by hammering, vibration experiment by simulated vibration generation simulator, analysis of frequency strength of board, characteristics of cross-country ski such as relationship between sliding speed and coefficient of kinetic friction were clarified. Furthermore, it was aimed to obtain basic materials of a sit ski development which is a Paralympic sports game using the cross-country ski.

The purpose of the present study is developing a novel protective headwear based on the strain rate effect of soft epoxy foam. Firstly, the strain rate and temperature effects on compressive property of soft epoxy foam were investigated. In order to increase the strain rate dependence on compressive property, the soft epoxy foams were fabricated with an soft epoxy resin whose compound rate of main and curing agents was shifted from stoichiometric ratio. Compression tests in wide range of strain rate were performed in several temperatures to evaluate strain rate and temperature effects on compressive property of the foam. In addition, impact tests assuming a head impact in daily life suggested that the proposed epoxy foams are effective as a cushioning material of a headwear.

Recently, various machines have been developed to facilitate physical work with the progression of technology. Especially, powered exoskeletons have been highly expected to be used for heavy labor and already designed for specific situations such as transporting injured people after natural disaster or agricultural work. Meanwhile, there are a few studies into assisting items at construction sites where carrying heavy materials is required. Therefore, this research has explored supporting methods for heavy labor such as carrying long objects at construction sites. Carrying long objects and flat boards, focused on repeating holding the arms at target position and lifting down slowly, the authors decided to assist upper limbs, especially two parts of muscles that are around the shoulder and elbow joints where the load applies. About the shoulder joint, the lock mechanism with gear rack assists holding, and small damper assists lifting down. Regarding the elbow joint, the mechanism using small brake assists holding. The possibility of the load reduction effect has been found by developing the tool, in experience of holding and lifting down structural plywood, focused on EMG.

The purpose of this study was to clarify the influence of using mobile while walking on gait parameters. Five males and two females who were graduate students participated five walking conditions: normal walking, walking with mobile, walking with typing on mobile, walking with watching website on mobile and walking with watching movie and listing music on mobile while treadmill walking. Motion analysis of gate using MAC motion capture system and eye-tracking using eye mark recorder: EMR-9 were measured. Step length, coefficient of variance on step length, standard deviation of mediolateral coordination on left heel and center of body trunk were analyzed while walking. Widely variation in step length was found at walking with typing on mobile in relation to other conditions significantly. Wobble of foot motion and sway of body were observed while walking with operating mobile. In this study, it was clarified that smartphone zombie had negative effect on gait parameters.

In this paper, the authors proposed a system for sending fire alarm information to the elderly with hearing loss. This system consists of following five elements: (1) electret condenser microphone for measuring a sound, (2) sound signal detection circuit for extracting only a fire alarm signal, (3) voltage frequency conversion circuit, (4) direct current voltage conversion circuit, and (5) vibration unit. If a fire alarm is generated, it was confirmed that the vibration unit was driven only when the fire alarm sounded. Next, the authors compared the perception time the sound of the fire alarm and the vibration of the vibration unit. Assuming bedtime, the vibration unit was installed under the pillow. The experiment was carried out in a room of 25.8m³. The subject placed in supine position, and attached ear plug and eye mask. By the alarm sound or vibration，the subject was stimulated at random at intervals of 30 seconds five times in three types of pillows. As a result of the comparison experiment, it was found that vibration has a shorter perception time than alarm sound. Furthermore, as a result of the one-way analysis of variance, the p value was less than 0.01. Therefore, made multiple comparisons, the significant difference of 5% of the significance level was observed between alarm and vibration.