吸能导向抗撞结构的主从关联耐撞性拓扑优化方法及概念设计

In the past optimization design of anti-collision structure, only the safety evaluation index must be satisfied. Although the safety evaluation index requires that the crash peak acceleration should be as small as possible while the peak deformation amount should be as small as possible in the past optimization design of anti-collision structure, the conflicting requirements has intersection set in the feasible region (it means that the existing optimization design method based on the monolayer programming will play important role in the this field). With the improvement of the safety regulations, the re-directive evaluation index of anti-collision structure has been added. However, the re-directive evaluation index requires the anti-collision structure to be of extremely high stiffness. Thus lead to the feasible region that simultaneously satisfies the crash acceleration and requirement of re-directive to be empty set. This new conflicting can’t be resolved by the existing optimal designing methods based on monolayer programming (i.e. all-in-one). This project bases on the theory of bi-level programming and researches the leader-followers joint crash-worthiness topology optimization method. Firstly, the integrated crash-worthiness topology optimization method of the anti-collision structure is studied to solve the problem of the synchronization optimization of the impact acceleration and structural deformation amount, which is not only suitable for the low-level optimization but also suitable for the top-level optimization of the bi-level programming. Then, the establishment of safety follower model based on the safety evaluation index is built. The re-directive stiffness compensation follower model can be built based on the goal that the path of force transmission of the safety follower model can be protected as much as possible. The joint effects of these two follower models are studied and the safe follower model is revised. The leader model is built by combined the revised safe follower model with the re-directive stiffness compensation follower model in order to obtain the whole non-inferior solution set of its topological configuration. At last, the multi objective satisfaction decision-making method of the final solution is researched based on the Signal/Noise ratio, thus the robust dimension parameters will be obtained. The correctness of the research results can be verified by the impact test. The conceptual designs of the anti-collision structure will be obtained. This research aims to present a new method for the optimization and conceptual design of energy absorption and re-directive anti-collision structure, and it is significant that this research facilitates the lightweight design of anti-collision structure.

以往的抗撞结构设计只需满足安全性指标，虽然它既要碰撞最大加速度小又要结构最大变形量小，但可行域有交集。随着安全法规的完善，新增了导向性指标，但导向性要求抗撞结构有极高刚度，使同时满足碰撞加速度与导向性要求的可行域为空集，现有单层规划优化方法不能解决此矛盾。项目基于双层规划，研究吸能导向抗撞结构的主从关联耐撞性拓扑优化方法及概念设计。首先研究既可用于双层规划底层又可用于顶层的抗撞结构一体化耐撞性拓扑优化方法，使碰撞加速度与结构变形量同步最优。然后针对安全性指标建立安全从属模型，以尽量保护安全从属模型传力路径为目标建立导向刚度补偿从属模型，研究两从属模型的关联影响，修正安全从属模型，将修正的安全从属模型与导向刚度补偿从属模型相结合建立主模型，获取其拓扑构型非劣解集。最后研究基于信噪比的多目标满意度最终解决策方法，获取稳健性参数，进行试验验证并获取概念设计。为抗撞结构的优化与概念设计提供新方法。

碰撞安全新法规在安全性指标基础上新增了导向性指标，导致同时满足二类指标的可行域为空集，现有拓扑优化方法不能获得该问题的解。.项目以发明导向刚度补偿装置为突破口，解决二类指标的矛盾：偏置碰撞时，导向刚度补偿装置抵抗弹性形变使车辆产生回正力矩以实现对车辆的导向；正向碰撞时，正常吸收碰撞能量，导向刚度补偿装置不会阻碍吸能过程，以保证乘员安全。.借鉴吸能导向的主从关联特性与双层规划，提出主从关联耐撞性拓扑优化方法。首先，建立初始优化模型，基于一体化耐撞性拓扑优化方法，获取初步拓扑构型；然后，结合人的创新性思维，配置导向刚度补偿装置，对初步拓扑构型进行导向刚度补偿，形成安全从属模型。随后，鉴于导向刚度补偿装置将影响结构的传力路径，需重新规划拓扑优化空间，构建带导向刚度补偿装置的主模型；最后，再次运用一体化耐撞性拓扑优化方法，获取主模型的拓扑构型，考虑结构设计其它要求，形成轮廓清晰的结构拓扑。.将稳健性设计方法与满意度函数相结合，提出基于信噪比与满意度的多目标稳健性设计方法：将可控因素置内表，噪声因素置外表，设计内外正交表并实验，获取各响应信噪比。用满意度函数转换信噪比，使之位于0到l之间，解决数据间的以大吃小问题。在得到单个响应的满意度后，获取多响应的总满意度，以最大化总满意度为目标，可得最优设计参数。对非劣解集重复此流程，求出每个解的信噪比及其最优设计参数，按信噪比对非劣解排序，信噪比最大的方案及其最优设计参数为拓扑构型最终解。.基于走廊评分法和动态时间弯曲距离算法，提出两种模型验证方法，解决仿真模型的验证问题，期间完成3次碰撞试验。.研究了独立桩抗撞结构的碰撞相容性优化、边界约束不清晰的横向受撞超长等截面结构的耐撞性局部拓扑优化、新型逃生管道多目标满意稳健性设计、“H”型吸能单元及其可导向防撞垫、抗撞结构桩基有限元材料模型参数的反演识别、SBm级钢护栏-混凝土组合式中央分隔带护栏设计问题。