力约束法在人体起跳动力学数值仿真中的应用

Force constraints in numerical simulation of jump movement dynamics of a human model

为描述人体步行、弹跳等运动过程中柔性鞋底和硬地面之间的接触柔性、微滑和摩擦特性,提出一个多点柔性接触模型,将鞋底与地面的单面几何约束转化为力约束。针对一个15刚体人体机构模型,得到一个不含机械回路约束方程的动力学全局仿真模型。然后,采用不同模型参数,数值仿真研究了双脚起跳过程中地面对鞋底的作用力。计算结果显示该模型能有效地揭示鞋底与地面接触的复杂作用过程,为用数值仿真方法研究人体与地面接触时的动力学提供了一个高效手段。

A multiplepoint to surface flexible contact model was developed to describe the deformation of contact area, microslip phenomena and effects of dry friction between the soft bottom of shoes and hard ground. Force constraints instead of unilateral geometry constraints were used to develop a set of secondorder ordinary differential equations of the dynamics for a 15 degree of freedom rigidbody human model to study various human motions. A jumpping movement was numerically simulated to study the reaction force between the shoes and the ground with different model parameters. The results show that the reaction is complicated and more careful study is needed. This work provides an efficient method to study human body dynamics with ground contact.