| 摘要 |
<p>The quality of dynamic behavior of tennis rackets and/or selected parts of tennis rackets is ascertained by vibrating the rackets and by monitoring one or more parameters of vibratory movement which are indicative of the quality of the corresponding part of or the entire racket. The rackets and/or selected parts of the rackets can be vibrated at a constant or at a variable frequency for selected intervals of time. The parameter may constitute the slope of the curves denoting the phase of vibration, the frequency of vibration, the width of the resonance frequency of the selected part and/or others.</p> |
