Simulation Of Off-road Vehicle With New Type Differential Based On Bond Graph Theory

Intellectual property is the core of all technologies, which makes the corresponding industry having the possibility to develop. Realizing the complicated function with the simpler machine is more significant.For the purpose of knowing and exploiting the nature, especially for the need of national defense, all the primary automobile manufacturing countries put the research of high off-road performance vehicle on a strategic height. The vehicle just can function normally with the invention of differential. But the equal torque distribution character of the symmetrical bevel gear differential restricts vehicle's off-road performance greatly. LSD (Limited Slip Differential) is a common way to solve this problem nowadays, but it distracts researchers' attention to develop auxiliary equipments that can resist the slip of driving wheel, which results in the complexity of the machine.For above reasons, a fully mechanic new type differential is carried out which consists of four conventional differentials. It reduces the complexity of vehicle's power train and increases the reliability as well. Besides those, it is convenient to maintain and can improve vehicle's off-road performance greatly.To study the dynamic behaviors of the new differential, bond graph theory which is a form of object-oriented physical system modeling is adopted. Considering the complexity of the new differential, the system is carefully studied from simple to complicated, from part to the whole. Finally, the model of the power train is built, which overcomes the shortcomings about power distribution and the effectiveness of the model existing in the previous issued papers/research. The state equation is deduced and the simulation based on MATLAB/Simulink software is realized.The compared simulation results show that the model of the power train with new type differential is correct; the off-road performance of the vehicle is greatly improved. The model built in this paper not only can be used in the analysis of vehicle longitudinal dynamics, but also is helpful to the development of this kind of new type differential.