Effect of the string diameter on dynamics characteristic of the string bed of tennis rackets

Abstract

In this study, Effect of the string diameter on dynamics characteristic of the string bed of tennis rackets were evaluated by rebound tests. Rebound tests between string-bed and tennis ball were conducted for 6-types of string-bed which diameter of string and distance of strings were different. Strings of 1.10 mm and of 1.60 mm in diameter were made for only this test. Because displacement sensor enabled to measure the contact state of the ball and the string-bed, contact time between string-bed and tennis ball and maximum amount of deformation of string-bed was measured. As a result, the distance of strings was longer, the contact time between string-bed and tennis ball was longer. In addition, while coefficient of restitution between string-bed and tennis ball was not related to the diameter of strings and the distance of strings, it was dependent on approaching velocity. Therefore, if string-bed had enough distance of strings, the big diameter string is available.