纵轴式掘进机横向和纵向随机振动响应的分析

Analysis of horizontal and vertical random vibration responses of longitudinal roadheader

为分析纵轴式掘进机在随机激励作用下的振动特性,利用拉格朗日方法建立其随机激励作用下横向和纵向的运动微分方程,以国产某型掘进机为例,针对截割头所受随机激励产生的随机振动,运用虚拟激励法导出了掘进机横向和纵向振动响应的数学模型,并利用Matlab汇编语言赋值求解,获得了该掘进机系统的固有频率和3阶振型以及在随机激励作用下截割头、悬臂和机体的位移响应特性。研究结果表明:系统的固有频率集中在低频7 Hz内,第2阶固有频率对掘进机振动影响较大。在外随机激励作用下,截割头和悬臂的横向位移响应幅值略小于纵向,机体的纵向位移响应幅值明显大于横向。为验证结论的可靠性,利用ADAMS对掘进机多刚体动力学模型仿真,理论值、模型仿真结果和实验数据较接近,证实该方法研究掘进机的随机振动可行。

In order to analyze vibration characteristics of a longitudinal roadheader under the influence of random exci- tations, horizontal and vertical differential equations of the roadheader were established by using Lagrangian equation, taking a domestic longitudinal roadheader as a example, for the cutting head suffers random excitations, the mathemati- cal models of horizontal and vertical vibration responses were derived by utilizing of the Pseudo excitation method. The natural frequency, the first three orders of vibration shapes, the responses of cutting head and boom and body were ob- tained by applying Matlab programs. The results show that natural frequency of system locates within 7 Hz, the natural frequency of the second order has greater effection on vibration of the system. The horizontal displacement responses of cutting head and boom are slightly less than the vertical, but the horizontal displacement responses of body are more than the vertical under random excitations. A multi-body dynamics model was simulated in ADAMS for the sake of identifying the conclusions. The theoretical value, the model simulation results and the experimental datas are relative- ly close, which imply validity of this method.