Abstract: Aiming at the problem of nonlinear dynamics of gear transmission system with clearance and friction, a bond graph model of the gear transmission system with clearance and friction is build based on the nonlinear features of tooth surface friction, time-varying gear mesh stiffness and gear clearance, in which modulated resistive element is used to describe the parameters of tooth surface friction characteristics and two modulated transformers are uded to present driving friction arm and driven friction arm respectively. Accordingly, the deformation of gear along the meshing line is divided into three statuses as gear clearance is the nonlinear function of piecewise-linear, thus the concept of switched power junctions is introduced to describe time-varying gear mesh stiffness with clearance that uses clearance as the signal, and flow source element(Sf) to represent the influences of the gear transmission error on the system. A spur gear pair is taken as an example, advanced software 20-sim is used to simulate the model. The results are compared with those from Matlab to check the bond graph model and verity its credibility.

Key words: Bond graph, Clearance, Friction, Gear, Modeling, Time-varying stiffness