满意度动态加权法在自卸车车架拓扑优化中的应用

Application of satisfiability dynamic weighting method in topology optimization of dump truck frame

为了使自卸车车架在满足使用性能的条件下达到轻量化的要求,将拓扑优化方法引入车架的结构设计过程中。以车架多工况权重刚度最大化为优化目标,以设计区域的体积分数为约束,以设计区域的材料密度为设计变量,建立了自卸车车架结构多刚度拓扑优化模型;在采用动态加权方法将多刚度这一多目标优化问题转化为单一目标优化的过程中,基于决策论中满意度理论提出了多工况权重比的计算方法。该方法使权重比的设定随每个单目标函数在每次迭代后的变化而自动调整,可避免传统方法中由于设计者主观因素造成的权重比偏差。仿真分析表明,车架性能满足工作要求,验证了车架设计的合理性。

To achieve the light weight requirement of dump truck frame considering its service performance,the topology optimization was introduced into the design of the frame structure.Taking the weight stiffness maximization of frame under multi-load conditions as the target of optimization,with the volume fraction as the constraint conditions and the material density as design variable,the multi-stiffness topological optimization model of dump truck frame structure was established.In the process of converting the multi-stiffnesses optimization problem into a single object optimization problem by adopting the dynamic weighting method,the calculation method of multi-load cases weight ratio was put forward based on the satisfiability method within decision theory.The weight ratio can be adjusted as the change of every object after each optimization.This method can avoid deviations of weight ratio caused by subjective factors on account of the designers in traditional method.The simulation analysis shows that the frame can satisfy the performance requirement,so the design of frame is verified.