基于约束层次化策略的钣金件贴模度计算

Springback gap computation of sheet metal part based on constrained and hierarchical strategy

为准确计算贴模度,考虑回弹变形对模型对齐的影响,提出一种基于约束层次化策略的贴模度计算方法。利用数字化模型统计分析回弹量,得到回弹阈值,剔除回弹变形点。通过约束优化实现了钣金件和模具模型的对齐,并基于该对齐结果进行了贴模度计算和回弹分析。贴模度不满足要求时,施加一定的载荷仿真装配应力,计算钣金件局部发生弹性变形后的贴模度。通过对U型仿真模型和飞机翼肋钣金件实测模型的实验,验证了所提贴模度计算方法的有效性和实用性。

To solve the problem of computing springback gap accurately, a computation method based on constrained and hierarchical strategy was presented by considering the influence of springback deformations on model alignment. The threshold of springback value was obtained from the statistical analysis of current springback, and the deformation points resulted from springback were pushed out. The alignment of sheet metal part and model was realized with constraints, and springback gaps computation was made on this basis. A certain load simulate assembly stress was added to sheet metal part when the springback gap were unqualified, and the springback gap was calculated un- der the load-deformation. The validity and practicability of proposed method was verified through the test on a U- shaped simulation model and a real aircraft rib.