纵轴式掘进机截割机构纵向随机振动的仿真研究

为了了解纵轴式掘进机的纵向振动特性，提高机器工作的可靠性，分析并确定截割头随机载荷的数学模型，利用拉格朗日方法建立了该型掘进机的纵向动力学模型，通过拉氏变换法对动力学方程解耦，得到了其3阶固有频率和振型.为进一步探究截割头与悬臂、悬臂与机体的刚度对截割头和悬臂振动的影响，利用虚拟激励法求得截割头、悬臂的纵向位移响应，并在ADAMS中对整机多刚体动力学模型仿真，验证了该方法的可靠性.研究结果表明：系统的纵向振动固有频率在6 Hz内，通过增加悬臂与机体的刚度能明显减小外随机激励作用下截割头和悬臂的振动.所得结论为改进掘进机设计和参数优化提供理论依据.

Simulation research on vertical random vibration of cutting unit at longitudinal roadheader

In order to find out the vertical vibration characteristics of longitudinal roadheader and improve its reliability，the mathematical model of random loads on cutting header were determined. Dynamic equations of the roadheader were established and sloved by using Lagrangian equation and Laplace transform，natural frequency and three orders of vibration shapes were obtained. To further explore the vibration characteristics，the effect of stiness between cutting head boom and boom body on the cutting header and boom was analyzed，the pseudo excitation method was used to calculate the displacement responses characteristic of cutting head and boom，and the reliability of the method was verified by simulating the multi body dynamics model with ADAMS. The results show that natural frequency of system locates within 6 Hz.Also，the increase of the stiffness between boom and body will significantly reduce the vibration of cutting head and boom under random excitations. These conclusions lay the foundations for improving design and parameters optimization of the longitudinal roadheader．