“担架——人体”振动系统的动力学特性分析

Dynamic Analysis for Stretcher-occupant Vibration System

采用国家标准GB/T 16440推荐的三自由度卧位人体垂直振动模型,建立了四自由度“担架－人体”系统动力学模型,并详细分析了固有频率和阻尼比对“担架－人体”系统垂直振动频响特性的影响规律。试验结果表明,四自由度模型比较符合“担架－人体”系统的实际振动情况。研究结果表明,通过改变固有频率调整“担架－人体”系统的频响特性更为有效,固有频率选择在6-10Hz范围内比较合适。

Using the vibration model of supine body with three-degrees of freedom introduced by GB/T 16440, dynamic model of stretcher-occupant vibration system with four-degrees of freedom has been established. By using the dynamic model, the effects of natural frequency and damping ratio on the frequency response of stretcher-occupant system are studied in detail. The results of vibration tests indicate that four-degrees of freedom model can reasonably characterize the dynamic response of stretcher-occupant system. The numerical calculation results indicate that to select natural frequency reasonably is a better approach to improve the frequency response of stretcher-occupant system, and the natural frequency should be selected between 6Hz and l0Hz.