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.
Journal of Central South University：Science and Technology