In vision-guided autonomous robots, object detectors play a crucial role in perceiving the environment for path planning and decision-making. However, adaptive adversarial patch attacks undermine the resilience of detector-based systems. Strengthening object detectors against such adaptive attacks enhances the robustness of navigation systems. Existing defenses against patch attacks are primarily designed for stationary scenes and struggle against adaptive patch attacks that vary in scale, position, and orientation in dynamic environments. In this paper, we introduce Ad_YOLO+, an efficient and effective plugin that extends Ad_YOLO to defend against white-box patch-based image attacks. Built on YOLOv5x with an additional patch detection layer, Ad_YOLO+ is trained on a specially crafted adversarial dataset (COCO-Visdrone-2019). Unlike conventional methods that rely on redundant image preprocessing, our approach directly detects adversarial patches and the overlaid objects. Experiments on the adversarial training dataset demonstrate that Ad_YOLO+ improves both provable robustness and clean accuracy. Ad_YOLO+ achieves top-1 clean accuracy on the COCO dataset and top-1 robust provable accuracy against pixel square patches anywhere on the image for the COCO-VisDrone-2019 dataset. Moreover, under adaptive attacks in AirSim simulations, Ad_YOLO+ reduces the attack success rate, ensuring tracking resilience in both dynamic and static settings. Additionally, it generalizes well to other patch detection weight configurations.
Object detection is used to automatically identify and locate specific objects within images or videos for applications like autonomous driving, security surveillance, and medical imaging. Protecting object detection models against adversarial attacks, particularly malicious patches, is crucial to ensure reliable and safe performance in safety-critical applications, where misdetections can lead to severe consequences. Existing defenses against patch attacks are primarily designed for stationary scenes and struggle against adversarial image patches that vary in scale, position, and orientation in dynamic environments.In this paper, we introduce SAR, a patch-agnostic defense scheme based on image preprocessing that does not require additional model training. By integration of the patch-agnostic detection frontend with an additional broken pixel restoration backend, Segment and Recover (SAR) is developed for the large-mask-covered object-hiding attack. Our approach breaks the limitation of the patch scale, shape, and location, accurately localizes the adversarial patch on the frontend, and restores the broken pixel on the backend. Our evaluations of the clean performance demonstrate that SAR is compatible with a variety of pretrained object detectors. Moreover, SAR exhibits notable resilience improvements over state-of-the-art methods evaluated in this paper. Our comprehensive evaluation studies involve diverse patch types, such as localized-noise, printable, visible, and adaptive adversarial patches.