基于变尺寸栅格地图的船载激光雷达目标检测

Target Detection of Shipborne Lidar Based on Variable Size Grid Map

激光雷达具有测距精度高、受环境因素影响小及全天时工作的特点,非常适合用于无人船障碍物检测。由于激光雷达点云近密远疏,基于栅格地图的海上障碍物检测的精度就会受到栅格尺寸大小的直接影响。建立了一种栅格尺寸线性增长的变尺寸栅格地图,结合高度差判别法和八邻域连通分量标记法进行栅格划分及聚类,通过盒子模型提取障碍物信息,得出更加精确的障碍物检测结果。开展了海上实船实验,并对所提方法与传统方法的处理结果进行了比较,对比处理结果可得,对于近岸处中小型渔船的检测,所提方法可有效地解决传统方法中栅格划分和聚类效果较差的问题,实现更精确实时的海上障碍物检测,为无人船避障提供数据支撑。

Light detection and ranging(LiDAR)offers the advantages of highranging accuracy,negligible environmental influence,and allday operation,making it suitable for unmanned ship obstacle detection.Since LiDAR point cloud is nearly dense and far sparse,the grid’s size has a direct effect on the accuracy of obstacle detection based on a grid map.In this study,a variable size grid map with a linear increase of grid size is established.The grid is divided and clustered using the height difference discrimination method and eightneighborhood connected component marking approach,and the obstacle information is extracted using a box model,yielding a more accurate obstacle detection result.The proposed method can effectively solve the problems of grid division and poor clustering effect in traditional approaches for the detection of small and medium fishing boats near shore,according to the results of a real ship experiment conducted at sea that compared the processing results of the proposed method with the traditional approach.The proposed method provides more accurate and realtime detection of obstacles at sea,as well as data support for unmanned ship obstacle avoidance.