Fig. 1. Lidar point clouds in different scenes. (a) Ground point clouds; (b) calm water surface point clouds

Fig. 2. Algorithm block diagram

Fig. 3. Lidar water surface echo data. (a) (b) Calm water surface; (c) (d) wave water surface

Fig. 4. DBSCAN filtering algorithm based on water surface point clouds

Fig. 5. DBSCAN clustering. (a) Wave point clouds over water; (b) clustering result

Fig. 6. Water surface target detection algorithm

Fig. 7. Structure of feature learning network

Fig. 8. VFE layer structure

Fig. 9. Region proposal network architecture

Fig. 10. Experimental platform

Fig. 11. Measured data. (a) Spheres; (b) tri-pyramid; (c) cylindrical; (d) multi-objective

Fig. 12. DBSCAN-VoxelNet loss value in the training process

Fig. 13. Construction of surface target detection simulation environment

Fig. 14. Virtual wave fluctuation state in the first view of ship

Fig. 15. Target setting of water virtual environment