Ultra-low altitude UAVs (below 120 meters) are gaining importance in the booming low-altitude economy, where GNSS signals are often unreliable or unavailable. Vision-based localization emerges as a promising alternative; however, existing benchmarks are not designed for ultra-low flight and typically adopt pinhole cameras with limited field of view, making them less effective in handling occlusions and repetitive textures near the ground. To address these limitations, we introduce the first panoramic UAV localization dataset tailored for ultra-low altitude scenarios. Built on a four-fisheye-camera system in the high-fidelity RflySim platform, our dataset captures diverse conditions — including day/night cycles, extreme weather, and dynamic obstacles — and contains over hundreds of thousands of frames. It is further enhanced with real-world UAV panoramic data to narrow the sim-to-real gap and will be continuously updated for broader applicability. Comprehensive experiments confirm the effectiveness and transferability of our dataset, establishing it as a robust benchmark for future research in vision-based UAV localization.

6D pose estimation is a central problem in robot vision. Compared with pose estimation based on point correspondences or its robust versions, correspondence-free methods are often more flexible. However, existing correspondence-free methods often rely on feature representation alignment or end-to-end regression. For such a purpose, a new correspondence-free pose estimation method and its practical algorithms are proposed, whose key idea is the elimination of unknowns by process of addition to separate the pose estimation from correspondence. By taking the considered point sets as patterns, feature functions used to describe these patterns are introduced to establish a sufficient number of equations for optimization. The proposed method is applicable to nonlinear transformations such as perspective projection and can cover various pose estimations from 3D-to-3D points, 3D-to-2D points, and 2D-to-2D points. Experimental results on both simulation and actual data are presented to demonstrate the effectiveness of the proposed method.

In V-SLAM, the estimation of relative camera pose is crucial to determine the spatial relationship between consecutive camera images, helping to accurately track the movement of the camera in its environment. In small indoor scenes, when the training set is limited, which is very common in robot SLAM, learning-based methods may fail to converge, especially the Transformer architecture, which requires a more substantial dataset to match the performance of the CNN architecture model. This work addresses this problem with the sharing attention mechanism, building on recent improvements in solving visual Transformer architectures on small datasets while incorporating messenger tokens. Besides, double-embedding is introduced to capture the spatial of images and order of images. In summary, we introduce an intuitive end-to-end relative pose estimation solution and prove its accuracy on the two smallest sub-datasets of 7Scenes. The proposed method is tested with a set of comparison experiments conducted across CNN-based, Transformer-based end-to-end relative pose estimation models, and the robust feature-matching non-learning method. Our model outperforms in all comparisons. Furthermore, ablation studies clearly illustrate that these innovations are crucial for the accuracy of relative pose estimation on small datasets.