Multi-material and multi-joint topology optimization for automotive lightweight design

随着政府对燃油效率和二氧化碳排放的新规定，汽车制造商面临着大幅减少车辆质量的巨大压力。例如，由于强制性的企业平均燃油经济性（CAFE），原始设备制造商必须从2016年开始到2025年通过一系列步骤显着改善车辆的里程。燃油经济性的要求将改变汽车的设计和制造方式，汽车制造商正在寻找各种可能的方法来减轻重量。拓扑优化决定了最佳的布局或材料分布，使重量最小化，同时保持重要的性能特征;这是最有效和最有前途的设计技术之一，以减少车辆重量。在车辆开发中，各种轻质材料的使用正在迅速增加，这就提出了一个新的设计挑战：“多种材料的最佳使用和分配以及最佳连接方法是什么？“传统的优化方法无法应对这一挑战，因此必须开发一种有效的方法，本研究的目的是（1）确定下一代汽车底盘连接策略的最佳设计，该策略利用混合材料和各种连接方法（2）通过开发多材料、多接头拓扑优化新技术，为加拿大通用汽车公司的轻型卡车梯形底盘车架进行了优化设计。总重量节省30%的目标，而不牺牲强度或刚度的框架。该项目的最终交付成果是下一代梯架总成的生产就绪设计，以及通用加拿大在其早期车辆架构开发阶段使用的优化软件模块。

With new government regulations on fuel efficiency and C02 emissions, automotive manufacturers are undertremendous pressure to reduce vehicle mass drastically. As an example, OEMs have to significantly improve vehiclemileage through a series of steps beginning in 2016 through to 2025 due to the mandated Corporate Average FuelEconomy (CAFE). The fuel economy requirements will transform the way in which vehicles are designed andmanufactured as automakers are looking at every possible means to reduce weight.Topology optimization determines the optimum layout or distribution of material that minimizes weight while maintainingimportant performance characteristics; and this is one of the most effective and promising design techniques forreducing vehicle weight. The use of various lightweight materials in vehicle development is rapidly increasing, and thisraises a new design challenge: "What are the optimum use and distribution of multiple materials and the optimum joiningmethods?" Conventional optimization approaches are ill equipped for this challenge, and it is imperative to develop aneffective approach that can determine the optimum use of the multiple, dissimilar materials and their joining methods.The objectives of this research are (1) to determine optimum designs of next generation vehicle chassis joiningstrategies which utilize mixed materials and various joining methods (2) by developing advanced topology optimizationapproaches for multiple material joint designs and joining methods.By developing new techniques for multi-material and multi-joint topology optimization, optimized designs will bedetermined for the ladder chassis frame of a light-duty truck by General Motors of Canada. A total weight savings of30% is targeted, without sacrificing the strength or stiffness of the frame. The final deliverables for the project areproduction ready designs for next generation ladder frame assemblies as well as optimization-software modules for useby GM Canada in its early vehicle architecture development stage.