Abstract: Provided are a digital twinning method and system for a scene flow based on a dynamic trajectory flow, which belong to the field of traffic control. The method includes: extracting and identifying a target semantic trajectory with a detecting and tracking integrated multi-modal fusion and perception enhancement network; extracting road traffic semantics, so as to obtain a highly parameterized virtual road layout top view; obtaining a road layout traffic semantic grid encoding vector based on the virtual road layout top view; constructing a target coupling relation model; constructing a traffic force constraint model; constructing a long short term memory trajectory prediction network; predicting a motion trajectory of a target with the long short term memory trajectory prediction network, so as to obtain the predicted motion trajectory; and obtaining a digital twin of the scene flow based on trajectory extraction, semantic identification and the predicted motion trajectory.

Abstract: A 3D target detection method based on multimodal fusion and a depth attention mechanism includes the following steps: obtaining and preprocessing original point cloud data and original image data; inputting the preprocessed point cloud data and image data into a 3D target detection network based on multimodal fusion and the depth attention mechanism, where the 3D target detection network based on multimodal fusion and the depth attention mechanism includes a generation phase for 3D bounding box proposals and a refinement phase for 3D bounding boxes, and the network outputs parameters and classification confidence of a target bounding box; training the 3D target detection network based on multimodal fusion and the depth attention mechanism; and processing the collected lidar point cloud data and image data by using the trained detection network, and outputting 3D target information, to realize 3D target detection.