著者

柴田 翔平 鳴尾 丈司 加瀬 悠人 稲毛 正也 山本 道治 森 正樹 浦川 一雄 廣瀬 圭 神事 努

出版者

一般社団法人 日本機械学会

雑誌

シンポジウム: スポーツ・アンド・ヒューマン・ダイナミクス講演論文集 2018 (ISSN:24329509)

巻号頁・発行日

pp.A-18, 2018 (Released:2019-05-25)

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The purpose of this study is to examine the accuracy of the system analyzing pitching data using baseball-type sensor (MAQ) and to measure kinematic parameter (ball velocity, spin rate, and spin axis) of baseball pitches by various pitchers. The accuracy of the developed system using a 3D motion analysis system and the high-speed cameras were examined. The spin axis of pitched ball was calculated from data of 12-axis sensor using the sensor fusion by extended Kalman Filter. The ball velocity and spin rate calculated by MAQ and the 3D motion analysis system showed similar values (ball velocity: r = 0.95 spin rate: r = 0.90). In several data, it was indicated that the spin axis calculated by MAQ, the 3D motion analysis system, and the high-speed camera showed similar values. In addition, there was a correlation between ball velocity and spin rate over the velocity range from 6.7 m/s to 41.0 m/s (n=188). From these results, the developed system can be used to evaluate baseball pitching skill with high accuracy.

著者

三村 泰成

出版者

一般社団法人 日本機械学会

雑誌

シンポジウム: スポーツ・アンド・ヒューマン・ダイナミクス講演論文集 2018 (ISSN:24329509)

巻号頁・発行日

pp.C-41, 2018 (Released:2019-05-25)

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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.

著者

草深 あやね 小林 裕央 三木 豪 桑田 真澄 工藤 和俊 中澤 公孝 若尾 真治

出版者

一般社団法人 日本機械学会

雑誌

シンポジウム: スポーツ・アンド・ヒューマン・ダイナミクス講演論文集 2018 (ISSN:24329509)

巻号頁・発行日

pp.A-32, 2018 (Released:2019-05-25)

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The purpose of this study was to verify the precision of different simulation methods to extrapolate vertical pitch location with the use of some dynamic parameters at ball release measured by TrackMan, and to determine dynamic parameters to predict pitch location. Ball trajectory was calculated by the equation of motion with three different numerical analysis methods (Euler, Runge-Kutta, Dormand Prince) and the vertical pitch location was compared with the measured values. The total number of pitches was 137 pitches. Dormand Prince method showed the smallest errors (5.8 ± 1.4 cm) compared with Euler (6.8 ± 1.4 cm) and Runge-Kutta (6.7 ± 1.4 cm) methods, indicating Dormand Prince was the highest precision method to extrapolate pitch location, but all methods could extrapolate it below the size of ball. Simulation with Dormand Prince method and multiple regression analysis revealed that elevation pitching angle and ball velocity more predicted vertical pitch location rather than other parameters. Furthermore, regression equation structured by these parameters could predict the pitch location with error by less than 10.0 cm (9.5 cm). These results indicate that the elevation pitching angle and ball velocity, i.e. velocity vector of ball, affected the determination of pitching location.

著者

塩谷 義

出版者

一般社団法人 日本機械学会

雑誌

シンポジウム: スポーツ・アンド・ヒューマン・ダイナミクス講演論文集 2018 (ISSN:24329509)

巻号頁・発行日

pp.C-21, 2018 (Released:2019-05-25)

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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.

著者

原田 雅隆 増田 新 小林 創 澁谷 颯之

出版者

一般社団法人 日本機械学会

雑誌

シンポジウム: スポーツ・アンド・ヒューマン・ダイナミクス講演論文集 2018 (ISSN:24329509)

巻号頁・発行日

pp.B-28, 2018 (Released:2019-05-25)

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In recent years, the number of patients with low back pain has increased, and it is a problem in various aspects such as health and economics. It is caused by a mechanical load acting on the muscles and the spine in the lumbar part. To reduce the risk of back pain, a support wear that reduces the load on the lumbar spine during flexion has been suggested by our group. This paper presents a dynamic model to calculate the load on the lumbar vertebrae. Especially, ligament tension considering Flexion Relaxation Phenomenon (FRP) which has not been considered so far and intra-abdominal pressure using two dimensional image information were modeled. First, the degree of FRP was measured from the myoelectric potential information of the back muscle in different bending postures. Next, we modeled the ligament tension using the results. Finally, the intra-abdominal pressure was incorporated into the model to calculate the compression force of the lumbar spine, and the experiment to estimate the lumbar load was performed. As a result, the experiment show that the load of the lumbar spine increases markedly due to FRP and this model is effective in calculation of the lumbar load compared to results of actual measurements of internal pressure.

著者

三上 隆 納土 賢悟 山代 和明 幾久 健 小山 遥陽 杉山 直磯 来田 宣幸

出版者

一般社団法人 日本機械学会

雑誌

シンポジウム: スポーツ・アンド・ヒューマン・ダイナミクス講演論文集 2018 (ISSN:24329509)

巻号頁・発行日

pp.B-14, 2018 (Released:2019-05-25)

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We have spent to walk the majority of the activities of daily living. We can reduce the burden on the foot by putting insoles in the shoes. In addition, insoles are used as part of rehabilitation. It can be proposed for the maintenance of a healthy life by studying the effect on the body due to the shape of the insole. This study focused on the thickness of the insoles and aimed to clarify the influence on the body when to use different insoles of the toe portion and the heel portion. Experimental subjects were opened with resting stance posture, both feet standing position and one-foot standing position. The condition of the insole was 5.5 ㎜ and 7.5 ㎜ in the thickness of the toes, and the heels were 5.0 ㎜ and 7.5 ㎜ in thickness. The experimental participants were four men in their twenties. The measuring device was a force plate. The sampling rate was 1000 Hz. From the result of the total trajectory length, it was confirmed that the center of gravity fluctuation becomes smaller by the insole.