Great Wall SAILOR Rear Axle Leaf Spring On Genetic Algorithms

The steady running of the automobile must be guaranteed by the reliable suspension system which transmits the load of the vehicle to wheels and absorbs the shock and vibration to the car body from the road through wheels. The rigidity, vibration and frequency of the suspension system have direct impactions on the stability, safety and comfortability of the car during its running. Therefore, reasonably designed suspension system is an important link of the automobile design.In the suspension system of the automobile, the dependent suspension composed of leaf spring is widely used in various cargo vehicles due to its simple structure, reliable performance and strong carrying capacity. For the convenience of computation, the mechanical model of the leaf spring is always simplified in the process of the early leaf spring suspension design. The design often needs plenty of empirical formulas and adjustment parameters. In computation, it is only necessary to meet basic mechanical property and kinematics performance of the suspension rather than precise simulation to mechanical state. As a result, it is quite hard to design an optimal structure for the leaf spring based on the practical situation.With the continuous development of the computer technology, optimization design algorithm, computer simulation and other new technologies, project planners can build more accurate leaf spring mechanical model with the powerful computing power of the computer. Under the support of CAD and CAE technology, the leaf spring designed can realize optimal computation with multiple targets and constraint conditions and generate solid model which may get more precise mechanical result through software of finite element analysis and is more convenient to verify the design effect.At present, for light truck, the excellent performance of taper-leaf spring is increasingly applied. Compared with traditional leaf spring, taper-leaf spring is light in mass, which reduces vehicle weight and fuel consumption and improves the stability in running. Sailing pick-up whose rear suspension is designed with traditional leaf spring structure produced by Baoding Great Wall Automobile is in the greatest demand in China. The traditional leaf spring of Sailing pick-up is turned into taper-leaf spring via the optimal design process with genetic algorithm. After the mathematical calculation,3D modeling will be carried out for leaf spring parts and assembly with the PRO ENGINEER software based on the structure size data obtained above. Meanwhile, we also build model for the original leaf spring parts and assembly. Then, make contrastive analysis for the two types of modeling with the software of finite element analysis.The final conclusion is that the leaf spring suspension assembly in rear axle of the Sailing pick-up after optimized with genetic algorithm is lighter than the original one and the stress condition of each leaf spring is also improved, resulting in longer service life. This optimal design achieves perfect design effect.