The effect on human body at the impact of tennis racket and balls from the viewpoints of mechanical characteristics of the grip

从握把力学特性看网球拍与球撞击时对人体的影响

• 批准号: 16500415
• 负责人: MAEDA Hiroshi
• 金额: $ 2.05万
• 依托单位: Oita University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16500415/
• 关键词: tennis racket; grip; impulse; vibration; link model; visco-elasticity model; simulation; リンク機械モデル

Experiments reveal clearly that when the vibration occurred at the impact of a ball and a racket, there are two kinds of frequency, one is high frequency around 130 Hz and another one is low frequency around 10 to 50 Hz. These results lead us to the conclusion that the racket acts as one is a vibration body and another one is a rigid object at the impact. This high frequency vibration disappeared when a ball impacts only just on the center of racket face, and low frequency remains on the racket. This law frequency vibration transmits to a hand and a forearm though. At the off center impact, when changing the rigidity of the grip from tight to loose, it was found that the high frequency was hard to transmit to a hand, but low frequency passed through the grip. Yoneyama, S. (2003) and other studies reported that the vibration after the impact may causes the "tennis elbow". The results of this experiment reveal that not only the vibration of high frequency but also the low frequency origi … More nates in the tennis elbow, when the racket is regarded as a rigid body.Findings from the experimental results show that the racket acts as a body with two types of properties, one is a vibration body and another one is a rigid object at the impact. From this point of view, we made a model of impact as a rigid body, and the racket links to a hand through a grip that has the characteristics of visco-elasticity. By means of this model, the characteristics of grip are investigated. The model was identified by comparing the experiment data such as the duration time of contact with the ball and racket, the coefficient of restitution of ball, the characteristics of damping of vibration, the frequency and the peak value of vibration. From the simulation of the model, it is inferred that the coefficient of viscosity of grip changes 1.0 to 5.5 N/m/s and the coefficient of elasticity changes from 50 to 500 N/m, according to the tightness of grip. As the tightness of the grip changes, the visco-elasticity coefficients of wrist joint are also influenced. Less

实验清楚地表明，当振动发生在球和球拍的影响下时，有两种频率，一个是高频约130 Hz，而另一个是低频约10至50 Hz。这些结果使我们得出这样的结论：球拍充当一个振动体，另一个是撞击处的刚性物体。当球仅在球拍的中心撞击时，这种高频振动就消失了，并且低频仍在球拍上。但是，该法律频率振动会传递到一只手和前臂。在离心中心的冲击下，当将握力的刚度从紧密变为松动时，发现高频很难将其传递到一只手，但是低频通过了握把。 Yoneama，S。（2003）和其他研究报告说，影响后的振动可能会导致“网球肘”。该实验的结果表明，不仅高频的振动，而且还出现低频原点……当球拍被视为刚性体时，网球肘部中的内部越来越多。实验结果的发现表明，球拍表明，球拍充当具有两种类型的特性的身体，一种是一种振动的身体，另一个是对撞击的刚性物体。从这个角度来看，我们制作了一个僵硬的身体模型，球拍通过具有粘弹性特征的握把链接到一只手。通过此模型，研究了握把的特征。通过比较实验数据（例如与球和球拍的接触时间，恢复球的核心，振动的舞蹈特征，振动的频率和峰值的特征）来确定该模型。从模型的模拟中，可以推断出，握把的粘度核心会根据握把的紧密度变化为1.0至5.5 N/m/s，弹性的核心从50 n/m变化为50 n/m。随着握把的紧密度的变化，手腕关节的粘弹性系数也受到影响。较少的

项目成果

Mechanical Characteristics of Tennis Grip

网球握拍的机械特性

• 发表时间: 2005
• 期刊: Proceedings of 18^<th> Symposium of Japanese Biomechanics Society
• 作者: Yasuharu Oishi;Tomonori Ogata;Hiroshi Maeda
• 通讯作者: Hiroshi Maeda

テニスにおけるグリップの粘弾性特性

网球握把的粘弹性特性

• 发表时间: 2005
• 期刊: トレーニングを科学するバイオメカニクス 第18回大会論集
• 作者: 杉浦春雄;杉浦浩子 他;前田 寛
• 通讯作者: 前田 寛

テニスラケットにおける低周波衝撃の振動伝播

网球拍中低频冲击的振动传播

• 发表时间: 2005
• 期刊: 日本体育学会第56回大会予稿集
• 作者: Hashimoto M.;Yamamoto N.;Sugawara M.;前田 寛
• 通讯作者: 前田 寛

The transmission of low frequencies vibration from tennis racket to hand

低频振动从网球拍传递到手

• 发表时间: 2005
• 期刊: Proceedings of 56^<th> Symposium of Japan Society of Physical Education, Health and Sport Science 260
• 作者: L-J.Guo;Y.Oshida et al.;Sugawara M.Hashimoto M.;Hiroshi Maeda
• 通讯作者: Hiroshi Maeda