Abstract:Aiming to solve the problems of path discontinuity, centerline deviation, poor real-time performance, and weak adaptability to complex environments in unstructured agricultural environments of robot navigation path extraction, a navigation path extraction method for agricultural scenes was proposed based on semantic segmentation and heatmap regression. Firstly, an improved Deeplabv3+ semantic segmentation model was constructed by integrating the lightweight MobileNetV3 as the backbone network, which effectively improved the inference speed of the model in embedded devices while maintaining a high segmentation accuracy. Secondly, based on the drivable area mask obtained by semantic segmentation, a Mobile-Unet lightweight heatmap regression network was designed. Through the combined loss function of weighted mean square error and perceptual loss, the model's ability to focus on high-response areas of the heatmap was enhanced, and the detail restoration and structural consistency of the heatmap prediction results were improved. Finally, a navigation path extraction algorithm combining heat value-guided greedy search and non-maximum suppression (NMS) was proposed to efficiently and stably extract continuous and smooth navigation paths from the heatmaps in complex agricultural environments. Experiment was carried out on a self-built agricultural scene dataset, which verified the performance of the semantic segmentation model, heatmap regression network and path extraction algorithm. Results demonstrated that the proposed method maintained high segmentation accuracy while achieving superior inference speed on the Jetson TX2 embedded platform. In heatmap regression tasks, the proposed Mobile-Unet combined with Mask input achieved the lowest mean square error (MSE) and the highest structural similarity (SSIM), meeting the requirements for real-time navigation. Overall, the proposed method took into account accuracy, speed and practical deployment capabilities, and had good application prospects in agricultural robot navigation.