High-speed video image analysis of ski jumping flight posture
High-speed video image analysis of ski jumping flight posture
复制标题
跳台滑雪飞行姿态高速视频图像分析
DOI：
10.1007/s12283-014-0157-z
复制
发表时间：
2014
影响因子：
1.7
通讯作者：
Yuji Ohgi and Reno Koyanagi
中科院分区：
文献类型：
--
作者：
Masahide Murakami;Masato Iwase;Kazuya Seo;Yuji Ohgi and Reno Koyanagi
根据120 m跳台滑雪飞行初始40 m段的高速视频图像，分析了实现大飞行距离的跳台滑雪飞行姿态。从视频图像中测量了前倾角和滑雪板迎角的时间变化，并从图像中获得的运动学数据计算了气动力。研究了初始速度修正后的飞行距离与起跳角度、初始过渡时间、气动力系数等参数之间的关系。结果表明：由于阻力小，在飞行初期小迎角是获得较大飞行距离的关键，而初学者最明显的缺点是过大的迎角和滑橇迎角导致气动失速。太小的阻力并不能为大的飞行距离提供最佳条件，因为升力也太小。高水平跳高运动员的升阻比大于0.95。
Ski jumping flight posture was analyzed for achieving large flight distance on the basis of high-speed video images of the initial 40 m part of 120-m ski jumping flight. The time variations of the forward leaning angle and the ski angle of attack were measured from the video images, and the aerodynamic forces were calculated from the kinematic data derived from the images. Some correlations were investigated between the initial-speed corrected flight distance and such parameters as the angles of jumper, the initial transition time and the aerodynamic force coefficients. The result indicated that small body angle of attack was a key for large flight distance in the initial phase of flight because of small drag force, and that the most distinctive fault of beginners was too large body angle of attack and ski angle of attack leading to aerodynamic stall. Too small drag force does not give an optimal condition for large flight distance because the lift force is also too small. The ratio of the lift to the drag was larger than 0.95 for advanced jumpers.