🤖 AI Summary
This work proposes a high-precision visual SLAM framework to address pose drift in short-term trajectories and the lack of high-frequency local optimization in existing Transformer-based systems. The front-end integrates a Visual Geometry Grounded Transformer (VGGT) with Sim(3) pose estimation, while the back-end introduces a novel fusion of dense digital elevation models (DEMs) and DINOv2 feature embeddings to construct compact subgraphs. High-frequency local bundle adjustment is triggered by visual place recognition (VPR), effectively suppressing short-term drift and accelerating graph optimization convergence. The method achieves state-of-the-art accuracy on standard benchmarks while preserving global consistency in large-scale environments through sublinear-time retrieval.
📝 Abstract
We introduce VGGT-SLAM++, a complete visual SLAM system that leverages the geometry-rich outputs of the Visual Geometry Grounded Transformer (VGGT). The system comprises a visual odometry (front-end) fusing the VGGT feed-forward transformer and a Sim(3) solution, a Digital Elevation Map (DEM)-based graph construction module, and a back-end that jointly enable accurate large-scale mapping with bounded memory. While prior transformer-based SLAM pipelines such as VGGT-SLAM rely primarily on sparse loop closures or global Sim(3) manifold constraints - allowing short-horizon pose drift - VGGT-SLAM++ restores high-cadence local bundle adjustment (LBA) through a spatially corrective back-end. For each VGGT submap, we construct a dense planar-canonical DEM, partition it into patches, and compute their DINOv2 embeddings to integrate the submap into a covisibility graph. Spatial neighbors are retrieved using a Visual Place Recognition (VPR) module within the covisibility window, triggering frequent local optimization that stabilizes trajectories. Across standard SLAM benchmarks, VGGT-SLAM++ achieves state-of-the-art accuracy, substantially reducing short-term drift, accelerating graph convergence, and maintaining global consistency with compact DEM tiles and sublinear retrieval.