基于OpenSim对负重蹲起动作的多体动力学仿真及验证

Many-body dynamics simulation and validation of bear-load squat based on OpenSim

目的:通过开源多体动力学软件OpenSim仿真计算负重蹲起动作的肌力变化规律。方法:选择一名男性田径运动员为研究对象,同步Vicon红外捕捉系统、AMTI测力台和表面肌电记录运动学、动力学与肌电数据,通过SoildWorks、Matlab及OpenSim软件建立人体负重蹲起的数学模型,并优化计算出相关肌肉群肌力。结果:股四头肌分别在30%与70%左右时刻出现两次峰值,其值为10000N和9060N;腘绳肌在31%和70%左右时刻出现两次峰值,其值为2046N和3901N;臀大肌与腓肠肌肌力(1803N、1514N)没有明显的峰值,但在整个深蹲过程中都有持续的收缩。结论:屈髋角度、伸髋力矩及主动屈膝力矩是准备阶段人-杠平衡的关键因素;在下降阶段和膝屈曲向膝伸展的转换阶段,下肢关节肌肉发力顺序应一致;股四头肌峰值出现在半蹲状态,此后股四肌力便不遵循肌肉-长度关系最佳化原理,此时腘绳肌为主要发力肌群;OpenSim动态优化算法在基于肌肉兴奋收缩耦联的基础上进行肌力计算,弥补了表面肌电与多刚体力学模型的不足。

Objective: To calculate the myodynamia variation of bear-load squat by OpenSim simulation of open source multi-body dynamics software. Methods: One male track and field athlete is selected as the study object.Vicon capture system, AMTI force platform and surface EMG recording kinematics, dynamics and electromuscular data are synchronized, a mathematical model of human bear-load squatting is established through SoildWorks, Matlab and OpenSim software, and the relevant muscle group myodynamia is optimized and calculated. Results: The femoral quadriceps peaked twice at around 30% and 70%, respectively, with 10,000 N and 9060N;peaked of the hamstrings twice at around 31% and 70%, 2046N and 3901N;gluteus and gastrocnemius(1803N、1514N), but continued efforts throughout the squat. Conclusions: 1) The hip bending angle,hip extension torque and active knee bending torque are the key factors in the human-bar balance in the preparation stage. 2) It should be consistent in the downward phase and the transition phase of the knee flexion to the knee extension of the knee. 3) The femoral quadriceps peak appears in the semi-squat state, after which the quadriceps strength does not follow the optimization principle of the muscle-length relationship. The hamstring muscle is the main force muscle group. 4) The OpenSim dynamic optimization algorithm performs muscle strength calculation based on muscle excitatory contraction coupling, compensating for the deficiency of surface EMG and multi-rigid body mechanical models.