Research on the Contact State Method Considering the True Topography of the Part Surface

In aircraft manufacturing and other assembly scenarios that require high product assembly accuracy, the true topography of the mating surface of the part is one of the important factors that affect the aircraft's aerodynamic shape, step difference, and other key characteristics. However, the existing Computer-Aided Tolerancing (CAT) system is difficult to express the true topography of the part surface and the mating simulation. To solve this problem, an analysis method that reflects the true contact state of the part is proposed—established a realistic assembly model containing the geometric information and the assembly force information of the part, designed the matching surface area segmentation and contact point search algorithm, and the contact state determination algorithm considering the assembly force. This paper takes the analysis of the contact state of step surface parts subjected to uniform assembly force as an example and compares the analysis results of commercial software packages and the difference surface method to verify the feasibility of this method.