Chen Hao, Hu Weijian, Yang Kailun, Bai Jian, Wang Kaiwei
Appl Opt. 2021 Jul 20;60(21):6264-6274. doi: 10.1364/AO.424280.
In this paper, we propose panoramic annular simultaneous localization and mapping (PA-SLAM), a visual SLAM system based on a panoramic annular lens. A hybrid point selection strategy is put forward in the tracking front end, which ensures repeatability of key points and enables loop closure detection based on the bag-of-words approach. Every detected loop candidate is verified geometrically, and the (3) relative pose constraint is estimated to perform pose graph optimization and global bundle adjustment in the back end. A comprehensive set of experiments on real-world data sets demonstrates that the hybrid point selection strategy allows reliable loop closure detection, and the accumulated error and scale drift have been significantly reduced via global optimization, enabling PA-SLAM to reach state-of-the-art accuracy while maintaining high robustness and efficiency.
在本文中，我们提出了全景环形同步定位与地图构建（PA-SLAM），这是一种基于全景环形透镜的视觉同步定位与地图构建系统。在跟踪前端提出了一种混合点选择策略，该策略确保了关键点的可重复性，并能够基于词袋方法进行回环检测。对每个检测到的回环候选进行几何验证，并估计（3）相对位姿约束，以便在后端执行位姿图优化和全局光束平差。在真实世界数据集上进行的一系列综合实验表明，混合点选择策略允许进行可靠的回环检测，并且通过全局优化显著降低了累积误差和尺度漂移，使PA-SLAM在保持高鲁棒性和效率的同时达到了当前最优的精度。
