Ball trajectory analysis of multimode cricket bowling machine

摘要

This paper is about the ball trajectory analysis of a multimode cricket bowling machine. The bowling machine is used to provide training for batsmen by emulating bowler's behaviour. This, in turn, reduces the risk of injuries experienced by bowlers. The experiments were divided into three groups namely ball velocity, bowling distance, and ball spin rate. For ball velocity under three machine speed settings, the measured data between dry and wet ball showed a difference in magnitude but with similar consistency. The optimal wheel pressure to produce the best dry ball velocity among those tested was 6.25 psi. The effect of speed ratio on the ball velocity was also observed from the measured velocity data where the ball velocity increase, as wheel's rotational velocity increases, peaked at 2000 rpm before decreasing. From the comparison between measured bowling length and line to that of calculations, the suitable drag coefficient value was 0.4 for estimating the ball trajectory. From the analysis, ball wetness, wheel pressure, and speed ratio were determined to be important in evaluating the performance of the cricket bowling machine.