School of Mechanical and Automotive Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
School of Vehicle and Mobility, Tsinghua University, Beijing 100084, China.
Sensors (Basel). 2022 Jul 4;22(13):5042. doi: 10.3390/s22135042.
High-accurate and real-time localization is the fundamental and challenging task for autonomous driving in a dynamic traffic environment. This paper presents a coordinated positioning strategy that is composed of semantic information and probabilistic data association, which improves the accuracy of SLAM in dynamic traffic settings. First, the improved semantic segmentation network, building on Fast-SCNN, uses the Res2net module instead of the Bottleneck in the global feature extraction to further explore the multi-scale granular features. It achieves the balance between segmentation accuracy and inference speed, leading to consistent performance gains on the coordinated localization task of this paper. Second, a novel scene descriptor combining geometric, semantic, and distributional information is proposed. These descriptors are made up of significant features and their surroundings, which may be unique to a traffic scene, and are used to improve data association quality. Finally, a probabilistic data association is created to find the best estimate using a maximum measurement expectation model. This approach assigns semantic labels to landmarks observed in the environment and is used to correct false negatives in data association. We have evaluated our system with ORB-SLAM2 and DynaSLAM, the most advanced algorithms, to demonstrate its advantages. On the KITTI dataset, the results reveal that our approach outperforms other methods in dynamic traffic situations, especially in highly dynamic scenes, with sub-meter average accuracy.
高精度、实时的定位是自动驾驶在动态交通环境中的基本且具有挑战性的任务。本文提出了一种由语义信息和概率数据关联组成的协同定位策略,提高了 SLAM 在动态交通环境中的定位精度。首先,基于 Fast-SCNN 的改进语义分割网络使用 Res2net 模块替代 Bottleneck 进行全局特征提取,进一步挖掘多尺度粒度特征,实现了分割精度和推理速度的平衡,在本文的协同定位任务中取得了一致的性能提升。其次,提出了一种新颖的结合几何、语义和分布信息的场景描述符。这些描述符由可能对交通场景具有独特性的显著特征及其周围环境组成,用于提高数据关联质量。最后,创建了一个概率数据关联,使用最大测量期望模型找到最佳估计。该方法将语义标签分配给环境中观察到的地标,并用于纠正数据关联中的误报。我们使用最先进的 ORB-SLAM2 和 DynaSLAM 算法对我们的系统进行了评估,以证明其优势。在 KITTI 数据集上的实验结果表明,我们的方法在动态交通情况下表现优于其他方法,特别是在高度动态的场景中,平均精度达到亚米级。