侧倾-垂向双轴激励下的坐姿人体生物动力学特性

Biodynamic characteristics of seated human body under roll-vertical vibration

研究了侧倾-垂向双轴激励下的坐姿人体动力学特性。测取了8名被试者在单轴随机侧倾振动下的动力学响应,通过人椅交界面处的角加速度和力矩定义了视在惯量,识别了人体在侧倾方向上位于1 Hz和2.5 Hz方向的两阶共振。随后引入垂向振动,对侧倾-垂向双轴激励下的人体响应开展频响函数分析与偏相干分析,分析了人体垂向响应与侧倾响应的耦合关系。研究发现,侧倾振动在0~10 Hz测试频率范围内对人体动力学响应特性几乎没有影响,垂向振动在两阶侧倾共振频率附近对包括模态频率、视在惯量幅值等侧倾动力学特性几乎没有影响。最后,面向侧倾与垂向振动激励,建立了人体动力学模型并识别了其中的动力学参数,实现了单一模型对双轴激励下人体响应的预测。

This paper presents a study on the biodynamic characteristics of seated human body under roll-vertical vibration.Initially,the dynamic responses of eight subjects under single-axis random roll vibration was measured.The apparent inertia was introduced,defined as the frequency response function between angular acceleration and torque measured at the interface between human body and seat.Two-order resonances of human body in the roll direction at 1 Hz and 2.5 Hz were identified.Subsequently,vertical vibrations were combined with the roll ones to investigate the human response under dual-axis roll-vertical vibration.Frequency response function analysis and partial coherence analysis were conducted,and the coupling between the vertical and roll responses of human body was discussed.The study revealed that roll vibration had minimal influences on the dynamic response of seated human body in the vertical direction within 0−10 Hz.Similarly,vertical vibration had negligible impact on human response in the roll direction around the first two resonance frequencies,including modal frequencies and associated modulus of roll apparent inertia.Finally,a dynamic model was established to represent the biodynamic characteristics of human body under combined roll and vertical vibration,and dynamic parameters of the model were identified.