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6名伞兵在跳伞平台上模拟跳伞着陆,采用高速摄影法记录,观察着陆姿势、着陆时的位移、速度和加速度等运动学特征,结果:①无负荷时,人体的重心较高,脊柱轴线与铅垂线的夹角较小;有负荷时相反。②有负荷时,耳屏、髂前上棘、大粗隆、桡骨、桡骨茎突和指尖等点在水平方向上的位移范围较大,在铅垂线方向上较分散;无负荷时相反,③有负荷时,各观测标记点的速度和加速度较大,且运动时间较长;无负荷时相反。④有负荷时,各节段与铅垂线的夹角比无负荷时大,大腿与小腿间、小腿与跖底平面间的夹角比无负荷时小,即有负荷时该相邻节段的弯曲度较大,无负荷时相反。上述运功学特征提示一条探索减小着陆冲击力的途径。
Six paratroopers simulated the parachute landing on the parachute platform and recorded them by high-speed photographic method. The kinematics characteristics such as landing attitude, landing displacement, velocity and acceleration were observed. Results: (1) When no load was applied, the body center of gravity was higher, Plumb angle smaller angle; the opposite when there is load. ② When there is a load, the horizontal displacement of the tragus, anterior superior iliac spine, greater trochanter, radius, styloid process and fingertip is larger in the horizontal direction and more dispersed in the vertical direction; when no load is applied, ③ When there is a load, the speed and acceleration of each observed point are larger and the exercise time is longer; on the contrary, no load. ④ When there is load, the angle between each section and the plumb line is larger than that under no load. The angle between the thigh and the lower leg and between the lower leg and the base of the plantar plane is smaller than that under the no-load condition. That is, The curvature of the larger, the opposite when no load. The above operational characteristics suggest a way to explore ways to reduce the impact of landing.