AGHL: Anchor-Guided Point Cloud Registration Network With Hybrid Local Feature Perception.

Abstract

Point cloud registration, which estimates a rigid transformation matrix between two point clouds, is a fundamental process in numerous applications. While existing detector-free techniques present exceptional performance, they overlook the extraction of hybrid local features that capture correlations between points and their neighbours, thereby limiting the quality of point cloud recognition. Moreover, these approaches typically treat point clouds as sequential data and employ the transformer to integrate global context from all points, which inevitably introduces interference from irrelevant regions, hence affecting the registration accuracy. In this work, we propose a novel detector-free approach AGHL to address these challenges. For the first issue, AGHL introduces a hybrid local feature perception module that designs two parallel branches to concurrently extract low-level and high-level local features, which effectively encode the correlations between each point and its neighborhood points in both Euclidean space and high-dimensional feature space. For the second issue, AGHL develops an anchor-guided cross attention that adheres to the local geometric consistency to constrain the network's attention on reliable anchors, thereby effectively suppressing interference from irrelevant regions. Benefiting from these techniques, AGHL achieves impressive point cloud registration accuracy across all synthetic, indoor, and outdoor datasets. Furthermore, we build an experimental platform and conduct a real-world robot localization experiment, with results showing the strong generalization ability of AGHL.