నైరూప్య

Strategic research on the probability statistics of free kick direct score based on biomechanical principles

Deding Tang, Ling Xu

To study about the key of free kick direct score, this paper will find out the movement trail of the swirling free kick based on the models of physics and probability statistics. Through consider we get the conclusion that there will be a lot of factors that affect the goalkeeper and the shooter: ball speed, rotation, the man wall, the way the ball get through the man wall, the goalkeeper’s psychological state, the way the goalkeeper saves, difficulty of shooting, goalkeeper’s physical condition and experience, shooter’s power, the deviation of the real trail and his accuracy, and the theoretical trail. After analyzing the scope that the goalkeeper can reach in some time, we can get a constraint equation of score. And by considering the instability of goalkeeper, the probability he can save a ball and the difficulty of shooting with other factors, we will finally get the best strategy.