Abstract

Panoramic map construction of polar sea ice can provide significant assistance for intelligent navigation and routing planning in polar regions. Traditional methods for panoramic observation and map generation suffer from issues such as limited parallax tolerance, poor stitching robustness, and low mapping accuracy. In this paper, these problems are addressed by a proposed online panoramic method based on multi-perspective image projection and camera pose rectification. The proposed method incorporates a modified inverse projection module that dynamically adapts to the ship's attitude, thereby stably restoring the sea-ice images into bird's-eye view (BEV) in real-time. In order to resolve the challenging sea-ice feature alignment under significant parallax, a planar feature registration method is proposed which robustly aligns the features between the projected images. Moreover, a camera pose rectification module is specifically designed for planar projection tasks, which virtually adjusts the camera's extrinsic parameters for obtaining more precise and high-quality panoramic sea-ice maps. Finally, online construction of global sea-ice field maps is achieved by fusing the local maps during navigation. Extensive qualitative and quantitative experiments demonstrate that the proposed method outperforms other panoramic methods in terms of map accuracy and stitching quality. Additionally, the proposed method is more suitable for downstream tasks, including polar simultaneous localization and mapping (SLAM) and path planning.