抓举过程中运动员的上肢运动学分析

Kinematical Analysis of Upper Limb During Squat Snatch

人体运动过程中,身体各部位的加速度、角加速度等运动学参数对计算关节力、关节力矩及肌肉力等动力学参数起着至关重要的作用。文章通过分析人体运动过程中关节坐标系相对世界坐标系的瞬时位置关系,以及各时刻关节坐标系空间位置关系,提出了基于关节坐标系的人体运动学参数计算方法。然后,以运动员抓举杠铃过程中的上肢运动为例,利用运动捕捉系统进行数据采集,计算出前臂在运动过程中的质心平移加速度和角加速度。结果表明,前臂质心总的平移加速度主要由竖直方向的分量构成,而角加速度主要在改变杠铃轨迹过程中产生。

The kinematical parameters such as translational acceleration and angular acceleration in each segment of human body play an important role in the calculation of the dynamic parameters such as joint force, joint torque, and muscle force during movement. The joint coordinate system （JCS） of human upper limb based on the anatomical landmarks was defined. A novel method based on the JCS for calculating the kinematical parameters was brought forward by means Of analyzing the relative position of the JCS to world coordinate system during instantaneous situation and relationship among each JCS at different time during body movement. Finally, a motion capture system was used to gather the data of the upper limb from an elite weight lifter during squat snatch and the method mentioned in forward was applied to analyze the data. The result showed that the total translational acceleration in center of mass mainly came from the vertical direction, while the angular acceleration was generated mainly in the process of changing the barbell trajectory.