Rigid-Flexible Coupling Dynamics Analysis On Working Device And Walking Mechanism Of Swamp Bulldozer

As the most widely used earth moving machinery, bulldozer plays an important role in key projects such as infrastructure and national defence,etc. The swamp bulldozer that works on coastal shoal and high moisture wetland is a special bulldozer, and it is on the base of conventional type bulldozer, by broadening track link and track gauge, using triangular track link and other measures to broaden the track’s ground contact area so as to reduce ground pressure, so that the bulldozer can play a better performance in wetlands. For this kind of structure-changed bulldozer, it is important to research on its main working parts. In this paper, we do some analysis on dozer blade’s pushing beam and walking mechanism’s walking frame.Firstly, this paper introduce the structure of dozer blade, and analyze its freedom of motion. The detailed analysis on the cutting resistance of dozer blade provides a theoretical basis for the simulation model’s cutting resistance loading. And make a theoretical analysis of the lift motion for dozer blade. Then, introduce the structure of walking mechanism, and analyze the cause of the walking system’s driving resistance and do the analytical calculation for the driving resistance.Then, combine with the parameters of bulldozer that this paper studies, and consider the complex stress and dynamic load effect of dozer blade and walking frame during the process of working under different conditions, and combine with the advantages of finite element analysis and rigid body dynamics analysis, using the rigid-flexible coupling dynamics analysis to establish the pushing beam and walking frame’s rigid-flexible coupling model respectively. Choose linear bulldozing and full-load swerving these two kinds of typical working condition, and the position that the maximum stress occurs on pushing beam through the simulated analysis is conformity with the theoretical dangerous section position. The forces on the joint parts between pushing beam and other parts have the same variation trend with the bulldozing resistance. When analyzing the walking frame, the maximum stress appears in the position of welding and casting structure on oblique support, which is similar to the actual situation, and the oblique support is easy to break in the wicked working condition of full-load swerving, so this paper put forward the measures of reinforcing a U-shaped plate, etc. For the track rollers’ forces are difficult to solve in the theoretical calculation, we can get the vertical forces distribution that are similar to the actual situation. And under the working condition of full-load swerving, we focus the analysis on the transverse forces of the track rollers, and get the conclusion that the bilateral rollers wear more serious. And the force analysis on carrier rollers indicates that the rear wheel wears more serious than the front wheel, we suggest to change the order of two wheels. The conclusion that obtained in this paper can provide a reference for the prototype simulation and improved design on bulldozer and other engineering machineries.