摘要针对非结构化环境下自主式地面车辆（ALV）的负障碍物检测问题，提出一种基于多激光雷达与组合特征的方法．首先，设计了一种具有互补能力的多激光雷达安装方式．其次，提出了基于幅向局部凸性和后沿壁局部密集特征的64线雷达负障碍物特征点对检测方法，以及基于径向距离跳变和后沿壁局部密集特征的32线雷达负障碍物特征点对检测方法．进而从负障碍物的时空融合角度，采用贝叶斯法则对多传感器多帧特征点对进行融合，然后采用DBSCAN（density-based spatial clustering of applications with noise）对融合后的特征点对进行聚类与过滤．最后对数据进行栅格化，提取负障碍物栅格．实验结果表明，本方法在非结构化复杂地形环境下具有良好的负障碍物检测性能．
Abstract：For negative obstacle detection of autonomous land vehicle (ALV) in unstructured environment, a method based on multiple LiDARs and compositional features is proposed. Firstly, a multi-LiDAR installation manner with complementary ability is proposed. Secondly, two methods are presented:a negative obstacle feature point pair detection method with 64-beam LiDAR based on local convexity in amplitude direction and local dense features at up-side of a ditch, and a negative obstacle feature point pair detection method with 32-beam LiDAR based on range jump in radial direction and local dense features at up-side of a ditch. From the view of spatial and temporal fusion of the negative obstacle, a Bayesian rule is adopted to fuse the feature point pairs from multiple sensors and multiple frames. Then the DBSCAN (density-based spatial clustering of applications with noise) algorithm is applied to clustering and filtering the feature point pairs after fusion. Finally, the data are discretized to extract negative obstacle grid. The experimental results show that the proposed method obtains a good performance for detecting negative obstacles in unstructured environment.
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