A Visual Perception Algorithm for AUV Dynamic Docking Based on Variable Markers

Autonomous Underwater Vehicle (AUV), as a key instrument for ocean exploration, utilizes dynamic docking technology to enable energy replenishment and data transfer among multiple AUVs, thereby extending the mission radius. A critical step in AUV dynamic docking is terminal visual positioning and perception. However, current unchanged markers based on point light sources cannot meet the requirements for perception range and dynamic performance.This paper designs a variable marker based on a line light source, whose emission angle can adaptively change according to the docking distance, thus increasing the sensing range and reducing dead zones. Faced with the issues of reduced brightness and increased noise for variable markers underwater, adaptive image enhancement is achieved by combining algorithm Recursive Least Square (RLS) with the image enhancement algorithm Multi-Scale Retinex with Color Restoration (MSRCR). The straight-line fitting algorithm for layer segmentation, combined with line light source information, effectively improves the success rate of visual perception and addresses the issue of key point loss in motion. This paper conducts visual recognition experiments on variable visual markers underwater, verifying the feasibility and accuracy of the proposed visual perception algorithm.