WTI-SLAM: a novel thermal infrared visual SLAM algorithm for weak texture thermal infrared images

This study addresses the challenges of robotic localization and navigation in visually degraded environments, such as low illumination and adverse weather conditions, by proposing a novel thermal infrared visual SLAM (Simultaneous Localization and Mapping) algorithm. The research introduces a new infrared visual odometry that integrates feature-based methods with optical flow techniques, enhancing image processing capabilities to mitigate the issues of high time overhead and cumulative errors in traditional feature-based odometry. Additionally, an improved bag-of-words model is employed to develop a novel loop closure detection method that addresses the challenge of scale drift. The purpose of this paper is to address the shortcomings in robustness and accuracy encountered by existing visual SLAM algorithms when processing low-texture thermal infrared images. Experimental validation using the JPL, Airey, and ViViD++ thermal infrared datasets demonstrates that the proposed algorithm exhibits superior real-time performance and robustness across various environments. Compared to mainstream thermal infrared visual SLAM algorithms, WTI-SLAM significantly improves the robot localization accuracy in weak-texture thermal infrared image scenarios, reducing the localization error by approximately 46%. This research offers an innovative and effective solution for achieving stable SLAM systems for robots operating in complex and visually degraded environments.