螺旋钻机变幅时机液耦合动力学的键合图建模

Dynamics model of mechanical-hydraulic coupling of auger driller during luffing motion by bond graph

为了从理论上研究螺旋钻机变幅机构内在的复杂动态特性,建立较精确的变幅机构数学模型。首先,分析螺旋钻机变幅机构的工作原理和结构特点,运用键合图理论对转动铰、油缸及立柱进行模块化建模,构建变幅机构基础单元的多体动力学模型;然后,建立变幅机构液压系统驱动力的键合图模型。通过分析各子模型的动态特性及相互作用规律,根据功率流传递路径,以统一方式建立变幅机构机液耦合动力学的键合图模型。研究结果表明:变幅油缸2腔压力的数值模拟结果与试验结果较吻合,表明该模型能预测机液耦合作用下系统的动态特性,可为分析和提高变幅机构的动力学性能提供参考。

In order to describe the inherent complex dynamic characteristics of luffing mechanism of auger driller, the accurate mathematic model of the luffing mechanism was established. The working principle and structural characteristics of the luffing mechanism were firstly analyzed, the bond graph model of revolute joint, cylinder and column were bulit, and the multi-body dynamics model for the basis unit was also constructed. Then the bond graph of hydraulic system was obtained. Through the analysis of the dynamic characteristics and interaction rules of each sub model, according to the transmission path of power flow, the mechanical-hydraulic coupling dynamic bond graph model of luffing mechanism was developed in a unified way. The results show that the two chamber pressure simulation results of the luffing cylinder agree well with the experimental results, which indicates that the system dynamic characteristics can be forecasted by this model, which provides a theoretical basis for improving the dynamic performance of the luffing mechanism.