A heterogeneous 3D map-based place recognition solution using virtual LiDAR and a polar grid height coding image descriptor

Abstract Place recognition is widely used for global localization technology. However, the existing place recognition solutions are limited by the requirement for the same type of sensors to be used in both the localization process and the mapping process. Therefore, the existing heterogeneous 3D map cannot be used for place recognition directly with the existing methods, leading to underutilization of information. In addition, most of the existing global feature descriptors used in place recognition solutions are still not highly descriptive and perform poorly under changed viewpoint scenes. To resolve these challenges, this paper presents a place recognition solution using virtual light detection and ranging (LiDAR) and polar grid height coding image (PGHCI) descriptors in the existing heterogeneous 3D map. First, virtual LiDAR is proposed to generate a series of virtual scans that are similar to the real scan of the localization sensor from the existing map, overcoming the limitation of the existing place recognition methods. Next, a novel PGHCI descriptor for place recognition is generated, and a method that overcomes the recognition difficulty of changed viewpoints in the same scene is presented. Two weighted distances for similarity estimation are analyzed, and the performance of the PGHCI descriptor with different parameters is evaluated. Finally, the performance of the PGHCI descriptor and the solution proposed in the paper is evaluated on several popular benchmark datasets and our own dataset. Comprehensive experiments demonstrated that the PGHCI descriptor has higher descriptiveness and is robust with respect to the changed viewpoint scene, as shown by the comparison of precision-recall (PR) curves using datasets with multiple scenes. The proposed place recognition solution has 100% success rates in the evaluation exclude under occluded conditions, showing that it is feasible to achieve robust place recognition using a heterogeneous 3D map.