🤖 AI Summary
To address spatial information loss in voxel-based methods and limited structural modeling capacity in point cloud–based approaches for 3D semantic occupancy prediction, this paper proposes a dual-modal representation integrating 3D Gaussian sets with sparse point clouds. We introduce the first collaborative modeling framework featuring an adaptive cross-modal fusion mechanism and layer-wise dynamic point cloud optimization, built upon a Transformer architecture, 3D Gaussian parameterization, query-driven semantic decoding, and multi-scale feature fusion. The method preserves high spatial localization accuracy while significantly enhancing voxel-level structural modeling capability. Evaluated on the Occ3DnuScenes benchmark, it achieves substantial IoU improvements over existing state-of-the-art methods, demonstrating superior geometric fidelity and semantic accuracy.
📝 Abstract
3D semantic occupancy has rapidly become a research focus in the fields of robotics and autonomous driving environment perception due to its ability to provide more realistic geometric perception and its closer integration with downstream tasks. By performing occupancy prediction of the 3D space in the environment, the ability and robustness of scene understanding can be effectively improved. However, existing occupancy prediction tasks are primarily modeled using voxel or point cloud-based approaches: voxel-based network structures often suffer from the loss of spatial information due to the voxelization process, while point cloud-based methods, although better at retaining spatial location information, face limitations in representing volumetric structural details. To address this issue, we propose a dual-modal prediction method based on 3D Gaussian sets and sparse points, which balances both spatial location and volumetric structural information, achieving higher accuracy in semantic occupancy prediction. Specifically, our method adopts a Transformer-based architecture, taking 3D Gaussian sets, sparse points, and queries as inputs. Through the multi-layer structure of the Transformer, the enhanced queries and 3D Gaussian sets jointly contribute to the semantic occupancy prediction, and an adaptive fusion mechanism integrates the semantic outputs of both modalities to generate the final prediction results. Additionally, to further improve accuracy, we dynamically refine the point cloud at each layer, allowing for more precise location information during occupancy prediction. We conducted experiments on the Occ3DnuScenes dataset, and the experimental results demonstrate superior performance of the proposed method on IoU based metrics.