FI-SLAM: Feature Fusion and Instance Reconstruction for Neural Implicit SLAM

Recent advancements in neural implicit fields for Simultaneous Localization and Mapping (SLAM) have provided breakthroughs. However, the benefits of reconstruction results to the perception ability of robot are minimal. Therefore, we propose FI-SLAM, a dense semantic instance SLAM system based on neural implicit representation, which significantly aids robots in better understanding the scene. FI-SLAM employs a coordinate and plane joint encoding method, which reduces the difficulty of feature storage by flattening the feature space. Furthermore, to improve representation efficiency, we use the method of adjacent feature level linear interpolation to describe features. We propose a feature fusion (FF) method to merge the object features with the scene features. The fused feature vector enhances the reconstruction accuracy of the local scene while ensuring the global reconstruction effect. It has improved the global reconstruction effect of the scene and the accuracy of camera tracking. Numerous experiments on synthetic and real-world datasets demonstrate that our method can assure accurate tracking precision, high-fidelity reconstruction results, and complete semantic instance maps. In summary, the algorithm we proposed heavily augments the scene perception capabilities of robot.