融合天空偏振光的视觉SLAM研究进展与展望

Progress and Prospects of Polarized Skylight Fused Visual SLAM

模仿生物复眼对偏振光敏感机理的偏振光导航是近年兴起的新技术,具有稳定、无源及完全自主的特性,偏振传感器的小型化、一体化使其与低成本相机、惯性测量单元等有效集成成为可能。回顾分析多传感器融合的视觉同时定位与地图创建(Simultaneous Localization and Mapping,SLAM)解决方案,梳理偏振导航传感器、天空偏振模式等最新研究进展,进而通过对辅以天空偏振光的视觉-惯性导航系统(Visual-Inertial Navigation System,VINS)的探索,进一步阐释该方案是应对视觉SLAM室外长航时导航实际的可行解。在此基础上,指出面向室外机器人操作系统、图优化框架的偏振成像仪定向观测约束模型的挑战性问题,供研究者探讨。所开发的偏振光辅助的VINS-Fusion具有扩展绝对位姿约束边的图优化技术特色,可实现全局一致的导航轨迹跟踪,为遥感测绘、军事探索等任务中的自主移动机器人导航与定位提供了创新性技术支持。

The polarized light navigation that imitates the mechanism of polarized light perception of compound eyes is a newly developed technology,which is stable,passive and totally autonomous.The miniaturization and integration of polarization sensors is currently enabling its fusion with low-cost cameras,inertial measurement units(IMU),etc.The solutions for multi-sensor-based simultaneous localization and mapping(SLAM)are firstly reviewed and analyzed.The research progress in polarization navigation sensors and skylight polarization modes are summarized.Then,the polarized light-aided visual-inertial navigation system(VINS)is explored,and this solution is proved to be feasible for outdoor long-term visual SLAM.The challenging problems of polarization imager model that provides directional observation constraint for the whole navigation system are pointed out in terms of outdoor robot operation system(ROS)and graph optimization for reference.The pipeline design of polarized light-aided VINS-Fusion has the technical characteristic of expanding the absolute pose constraint edges of the graph,and further enables the globally consistent navigation trajectory tracking,providing innovative technical supports for autonomous mobile robot navigation and positioning in remote sensing,mapping and military exploration tasks.