Wilson J F, Davis J S
Department of Civil Engineering, Duke University, Durham, NC 27706, USA.
J Biomech Eng. 1995 Nov;117(4):479-84. doi: 10.1115/1.2794211.
Measured in this study was the effectiveness of two types of retrofits in mitigating shocks in tennis rackets with ideally high grip fixity. The retrofits were a cushioned grip tape and a string implant device. Three types of rackets were investigated: wood, graphite composite, and metal. For low speed ball impact, neither retrofit changed significantly the magnitude and distribution of e, the coefficient of restitution on the racket heads. For moderate ball speeds impacting the rackets along the vertical centerline, three dynamic racket responses were measured: the free vibration damping based on racket head acceleration, the root-mean-square (rms) grip reaction force, and the fast Fourier transform (FFT) of the grip force. These latter experiments showed that the string implant device had a negligible effect on the three dynamic measures of racket response. However, the cushioned grip tape increased racket damping by up to 100 percent, reduced the rms grip force by about 20 percent, and reduced the magnitude of the FFT of this force by about 40 percent.
本研究测量了两种改进措施在具有理想高握把固定性的网球拍中减轻震动的效果。这两种改进措施分别是带缓冲的握把胶带和弦植入装置。研究了三种类型的球拍：木质、石墨复合材料和金属材质。对于低速球撞击，两种改进措施均未显著改变球拍头部的恢复系数e的大小和分布。对于沿垂直中心线以中等球速撞击球拍的情况，测量了三种动态球拍响应：基于球拍头部加速度的自由振动阻尼、均方根（rms）握把反作用力以及握力的快速傅里叶变换（FFT）。后一项实验表明，弦植入装置对球拍响应的三种动态测量值影响可忽略不计。然而，带缓冲的握把胶带使球拍阻尼增加了高达100%，将均方根握力降低了约20%，并将该力的快速傅里叶变换幅度降低了约40%。
