Aerial Vision-and-Language Navigation (VLN) is an emerging task that enables Unmanned Aerial Vehicles (UAVs) to navigate outdoor environments using natural language instructions and visual cues. However, due to the extended trajectories and complex maneuverability of UAVs, achieving reliable UAV-VLN performance is challenging and often requires human intervention or overly detailed instructions. To harness the advantages of UAVs' high mobility, which could provide multi-grained perspectives, while maintaining a manageable motion space for learning, we introduce a novel task called Dual-Altitude UAV Collaborative VLN (DuAl-VLN). In this task, two UAVs operate at distinct altitudes: a high-altitude UAV responsible for broad environmental reasoning, and a low-altitude UAV tasked with precise navigation. To support the training and evaluation of the DuAl-VLN, we construct the HaL-13k, a dataset comprising 13,838 collaborative high-low UAV demonstration trajectories, each paired with target-oriented language instructions. This dataset includes both unseen maps and an unseen object validation set to systematically evaluate the model's generalization capabilities across novel environments and unfamiliar targets. To consolidate their complementary strengths, we propose a dual-UAV collaborative VLN framework, AeroDuo, where the high-altitude UAV integrates a multimodal large language model (Pilot-LLM) for target reasoning, while the low-altitude UAV employs a lightweight multi-stage policy for navigation and target grounding. The two UAVs work collaboratively and only exchange minimal coordinate information to ensure efficiency. Experimental results indicate that AeroDuo achieves an evident 9.71% improvement in success rates compared to existing single-UAV methods, demonstrating the effectiveness of dual-altitude collaboration in balancing environmental coverage, precision, and operational autonomy.

The goal of referring camouflaged object detection is to identify and segment the specified object hidden in the surroundings given text or images as references. The previous method still faces limitations in learning discriminative object features and comprehensively exploiting reference information due to coarse reference-image fusion upon disunified network components. In this paper, we propose a novel Reference Prompted Model Adaptation (RPMA) pipeline that employs rich and fine-grained semantic knowledge in a generic segmentation network to enhance the Ref-COD model’s capability. Within RPMA, we design a Cross Reference Adapter (CRA) to integrate reference information into the generic segmentation network to prompt reference-relevant camouflaged image features, and also devise a Reference-guided Dynamic Convolution (RDC) for foreground-background segmentation via reference-generated kernels. Extensive experiments on the Ref-COD benchmark show that our method achieves new state-of-the-art performance.