Tennis service technique and drop point relation?￠????s geometric and mechanical analysis

摘要

The paper firstly applies Lagrange equations to solve restricted particle kinetic equation, combines with theoretical formulas to analyze when tennis player serves, hand joint mechanical movement, combining with shoulder joint, elbow joint mechanical analysis to study on tennis service technology. According to geometric principle, it establishes tennis service model, when athlete serves, he should try to stretch arms to right ahead and to be vertical to service point, and then probability that ball passes through net will get larger. And apply mechanical conservation law to analyze tennis service problems, it gets that athlete himself can further control rotational angular speed by changing self-rotational inertia. Twist service is when athlete takes off and serves, carries out serving by changing upper body faced direction, when athlete jumps, it should increase athlete himself rotational angular speed, on the contrary, when athlete jumps to the highest point, athlete should try to adjust body stability and let rotational angular speed to reduce as much as possible.