中高频大振幅垂向振动下的坐姿人体7自由度建模及实验

建立合适的人体振动模型,预测人体在不同振动环境下的动力学响应和各部位振动的传递性,能够对建筑和交通工具内部的振动控制起到指导作用。到目前为止,大多数垂直振动下的人体多自由度模型都是针对较低频率(20Hz)和较小幅度(1.5 ms-2)的振动环境,未必适用于较高频率(20 Hz)和较大幅度(1.5 ms-2)的垂向振动环境。为了准确地预测坐姿人体对中高频、大振幅垂向振动的动力学响应,建立垂向振动下坐姿人体的7自由度修正模型,并通过实验测试25名志愿者在4种不同加速度幅值(1.0 m/s2、1.5 m/s2、2.0 m/s2、2.5 m/s2)的宽带随机(2~100 Hz)垂向振动下的视在质量。实验结果表明,相比ISO标准规定的3自由度模型,所提出的7自由度修正模型能较准确地预测坐姿人体对大振幅垂向振动的动力学响应。

7-DOF Modelling and Testing of Seating Human Bodies for Prediction of Responses to Large Magnitude Vertical Vibration at High Frequencies

In order to control the interior vibration of buildings and vehicles, a proper model of human body need to be developed to predict the dynamic response of the human body under different conditions. So far, most of the previous studies concerned on the biodynamic responses to vibration at relatively low frequencies (<20Hz) and small magnitudes (<1.5ms-2), which may not predict the human responses to vibration at relatively high frequencies (>20Hz) and large magnitudes (>1.5ms-2) well. The present study proposed a modified 7 degrees-of-freedom (DOF) model to predict the biodynamic response of the seated human body to the vertical vibration at relatively high frequencies and large magnitudes. An experiment was conducted to measure the apparent mass of the seated human body on 25 subjects (13 males and 12 females) with random vertical vibration at 2-100Hz and four different magnitudes (1.0、1.5、2.0、2.5m/s2). The experimental data were compared with the predicted data to identify the parameters of the 7 DOF model. The results showed that the modified 7 DOF model predicted the dynamic response of seated human body more accurately than the 3 DOF model in the international standard to the vertical vibration at frequencies higher than 20Hz and magnitudes larger than 1.0m/s2.