棒球击球碰撞过程中的动力学分析

Dynamic analysis on impacting during baseball batting

目的通过对棒球击球过程进行深入分析,建立简单有效的动力学模型,为球员训练提供理论依据。方法根据冲量矩理论,对多刚体铰接模型进行动力学分析,获得关于棒球击出速度的封闭线性方程组;通过求解得出数值解。结果 (1)通过计算得到棒球击出速度与不同初始球、棒速度的关系;(2)铝质球棒击出速度远大于木质球棒;(3)恢复系数对棒球击出速度影响较大,对击球甜区和碰撞中心位置无影响。结论利用动力学方程得出了各种条件下的棒球击球过程的数值结果,所得数值与参考文献中的实验数据一致,证明了动力学分析的正确性;分析过程简单,教练员和球员易于理解,可直接应用于棒球训练的理论指导。

Objective By a thorough analysis of the baseball batting to provide a theoretical instruction for baseball players with a simple and efficient dynamic model.Method Based on the moment of impulse theory,the closed form linear equations were derived by the dynamic analysis of the hinged multi-rigid body model.The numerical results would be obtained after solving the equations.Results（1） The batting speeds have been obtained by the numerical calculation under various conditions of different initial speeds of the baseball and bat;（2） The knockout speeds of wood bats are much smaller than the aluminum ones;（3） The coefficient of restitution has the significant effect on the batting speeds,and has no effects on sweet spot and center of position.Conclusions The numerical results are consistent with the data of experiments in reference.The calculating procedure is easy for baseball coaches and players to understand and can be applied in the training of baseball batting directly.