“…Other works differ in the deep neural network used (e.g., recurrent neural networks on consecutive frames [60], [9], 3D CNN for point clouds [16]), the map representation employed (point-cloud maps [52], [9] and voxel-based maps [60], [63], [33]), or the type of semantics (instance-level [19], object-level [52], [66], [45], [68] and place-level [51]). More recently, distributed semantic mapping for multi-robots [65], [26] and 3D scene graphs [44] are also trending research topics.…”