The dynamic impact characteristics of tennis balls with tennis rackets
Deutscher übersetzter Titel: | Die dynamischen Aufprallcharakteristiken eines Tennisballs auf den Tennisschläger |
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Autor: | Haake, S.J.; Carré, M.J.; Goodwill, S.R. |
Erschienen in: | Journal of sports sciences |
Veröffentlicht: | 21 (2003), 10, S. 839-850, Lit. |
Format: | Literatur (SPOLIT) |
Publikationstyp: | Zeitschriftenartikel |
Medienart: | Gedruckte Ressource |
Sprache: | Englisch |
ISSN: | 0264-0414, 1466-447X |
DOI: | 10.1080/0264041031000140329 |
Schlagworte: | |
Online Zugang: | |
Erfassungsnummer: | PU201001001146 |
Quelle: | BISp |
Abstract
The dynamic properties of six types of tennis balls were measured using a force platform and high-speed digital video images of ball impacts on rigidly clamped tennis rackets. It was found that the coefficient of restitution reduced with velocity for impacts on a rigid surface or with a rigidly clamped tennis racket. Pressurized balls had the highest coefficient of restitution, which decreased by 20% when punctured. Pressureless balls had a coefficient of restitution approaching that of a punctured ball at high speeds. The dynamic stiffness of the ball or the ball-racket system increased with velocity and pressurized balls had the highest stiffness, which decreased by 35% when punctured. The characteristics of pressureless balls were shown to be similar to those of punctured balls at high velocity and it was found that lowering the string tension produced a smaller range of stiffness or coefficient of restitution. It was hypothesized that players might consider high ball stiffness to imply a high coefficient of restitution. Plots of coefficient of restitution versus stiffness confirmed the relationship and it was found that, generally, pressurized balls had a higher coefficient of restitution and stiffness than pressureless balls. The players might perceive these parameters through a combination of sound, vibration and perception of ball speed off the racket. Verf.-Referat