Scanned point cloud registration for localization of aircraft access panel and complementary frame with weak features

The quality of trimming access panels on aircraft skin directly affects flight safety and aerodynamic characteristics of aircraft. It is crucial to obtain the trim allowance accurately in a single attempt. However, access panels and their complementary frames are thin-walled components with random surface curvature and weak features, making precise localization challenging. We propose a new efficient and precise localization framework that aligns the scanned point clouds of the access panel and complementary frame to their standard model. We design a contour inflection point feature (CIF) descriptor that facilitates feature retrieval and matching during the alignment process and addresses issues of weak features leading to matching errors. Additionally, we propose a proportional segmented weighted ICP (PSW-ICP) method for precise alignment, which overcomes the problem of local optima in the alignment process due to contour differences. Experiments with multiple types of access panels demonstrate that the proposed registration method significantly outperforms existing algorithms in terms of accuracy and efficiency, achieving a mean localization error of less than 0.07 mm. This provides valuable guidance for the digital assembly of aircraft skin.