π€ AI Summary
To address tracking failure in visual servoing under partial or complete target occlusion, this paper proposes a hybrid tracking framework integrating deep feature alignment with sequential prediction. Methodologically, it jointly leverages early-layer VGG deep features, an enhanced deep LucasβKanade optical flow estimator, and a lightweight residual regressor for high-accuracy pose estimation. When tracking confidence drops, a GRU-based predictor seamlessly takes over, forecasting translational, rotational, and scale transformations from historical motion sequences to ensure continuous control signal generation. Evaluated on handheld videos with up to 90% occlusion, the method achieves sub-2-pixel tracking error and sustains real-time closed-loop control at 30 Hz. It significantly enhances robustness, accuracy, and responsiveness under severe occlusion, establishing a novel paradigm for robotic visual servoing in complex, dynamic environments.
π Abstract
Vision-based control systems, such as image-based visual servoing (IBVS), have been extensively explored for precise robot manipulation. A persistent challenge, however, is maintaining robust target tracking under partial or full occlusions. Classical methods like Lucas-Kanade (LK) offer lightweight tracking but are fragile to occlusion and drift, while deep learning-based approaches often require continuous visibility and intensive computation. To address these gaps, we propose a hybrid visual tracking framework that bridges advanced perception with real-time servo control. First, a fast global template matcher constrains the pose search region; next, a deep-feature Lucas-Kanade module operating on early VGG layers refines alignment to sub-pixel accuracy (<2px); then, a lightweight residual regressor corrects local misalignments caused by texture degradation or partial occlusion. When visual confidence falls below a threshold, a GRU-based predictor seamlessly extrapolates pose updates from recent motion history. Crucially, the pipeline's final outputs-translation, rotation, and scale deltas-are packaged as direct control signals for 30Hz image-based servo loops. Evaluated on handheld video sequences with up to 90% occlusion, our system sustains under 2px tracking error, demonstrating the robustness and low-latency precision essential for reliable real-world robot vision applications.