蹦床运动的动力学测试与建模分析

Trampoline gymnastics is an exercise that a trampolinist performs a series of difficult and beautiful movements on the elastic trampoline bed. The beauty of a trampoline performance is highly dependent on the combination of trampolinist and the rhythm of the elastic trampoline bed. At present, trampoline net researches mainly focus on up and down movement of the center point, which is within one-dimension. The vibration characteristics of the trampoline athletes were not considered in the whole system. However, the mechanical model of trampoline combined with human motion analysis work has not been reported yet. In this project, the static and dynamic analysis on three dimensional stress and deformation of trampoline net will be investigated. The stress and deformation law, trampoline natural frequency and vibration mode parameters of the trampoline will be obtained. Based on these data, the three-dimensional finite element model of trampoline will be established. The biomechanics model of trampoline athlete will be established through motion tracking test. The characteristics and rules of every movement can be obtained with the coupled analysis between biomechanics model of trampoline athlete and three-dimensional finite element model of trampoline. This work will provide a theoretical basis of technical diagnosis and training methods improvement for athletes, and may contribute to the development of trampoline career in China.

蹦床运动是指运动员借助蹦床网面的弹力弹向空中，在空中做各种技巧性动作的运动项目，蹦床比赛需要蹦床运动员结合蹦床网面的弹力，将每个蹦床动作完美的协调和连贯起来。目前蹦床网面力学特性主要集中在中心点的上下移动，为一维研究；动态特性研究也没有考虑网面振动特性，而将蹦床模型与运动员人体运动模型进行耦合分析的工作尚未见报道。本项目拟对蹦床网面进行三维受力与变形的静力测试和动态振动测试分析，得到相应的受力变形规律、蹦床固有频率和振型参数，并在此基础上建立蹦床的三维有限元动力学模型；通过运动跟踪测试技术分析，建立蹦床运动员的运动生物力学模型；对运动生物力学模型与蹦床三维有限元模型进行耦合分析，找出蹦床运动中每一个动作的用力特点和规律，为蹦床运动员的技术诊断和改进训练方法提供理论依据。

蹦床运动是蹦床运动员借助蹦床网面的弹力将其弹向空中做一系列技巧性动作的运动项目。本项目主要研究内容分为两个部分，即蹦床网面和蹦床运动。对于蹦床网面主要是掌握网面不同区域的弹性形变和频率特性进而分析得出网面的整体力学特性和振动频率；对于蹦床运动主要研究从单一动作的运动生物力学特征到各个动作之间的协调配合，进一步找出蹦床运动与蹦床网面之间的互动原理以及内在规律。针对以上研究内容，课题组设计了静态加载装置，通过测试得到蹦床网面中心区域的加载力与水平位移、垂直位移的关系，进一步得出了蹦床网面的水平刚度和垂直刚度；通过有限元分析得到了蹦床网面整体加载的应力云图；此外，还对蹦床网面进行了振动的测试分析，得到了其振动曲线为非线性，是多自由度受迫振动。对蹦床运动员垂直起跳、空中翻转以及着网阶段进行了多刚体运动学和动力学分析，得到了运动员和网面的若干定量及定性的力学关系，这些关系力图从生物力学方面完善蹦床运动的本构关系，确定蹦床运动的技术原理，与运动员空中动作的实现以及入网姿势的调节密切相关，可以作为蹦床运动员的技术诊断和改进训练方法的理论依据，有助于我国蹦床运动事业的发展。