高级检索+

基于YOLO11n改进的自然环境下云南澳洲坚果花识别

Improved YOLO11n-based Detection of Yunnan Australian nut flowers in natural environments

  • 摘要: 为实现复杂自然环境下云南澳洲坚果花序发育状态的高精度实时检测,提出了一种基于改进YOLO11n的目标检测方法。设计了多尺度特征聚合(partial multi-scale feature aggregation,PMSFA)模块,可高效捕获并聚合多源异构特征信息以显著提升复杂背景下花序的检测精度;通过引入分组混合卷积(group-shuffle convolution,GSConv)替换传统卷积模块,并以跨阶段局部模块(variety of view group shuffle cross stage partial network,VoV-GSCSP)替代C3k2模块,构建Slim-neck架构以保障高识别精度的前提下,优化特征融合效率并有效控制计算负载;将YOLO11n的损失函数由CIoU(center intersection of union)替换为Focaler-PIoU v2,以增强检测器对花序关键特征的聚焦与定位能力。试验结果表明:改进后的YOLO11n模型IoU=0.5时的平均精度均值(mean average precision,mAP)达92.4%,较原始YOLO11n基线模型提高了3.6个百分点;相较于经典Faster R-CNN、SSD、RT-DETR、YOLOv5s、YOLOv8n、YOLOv10n和YOLO12n,改进模型mAP0.5分别高出6.4、15.9、5.7、4.3、4.1、5和3.3个百分点。通过在Orange Pi AI Pro边缘计算平台上部署与多线程优化,改进的YOLO11n模型检测速度可达72.8帧/s,能有效满足自然环境下云南澳洲坚果花实时精准识别的实际需求。该研究为云南澳洲坚果花期智能化调控装备的开发提供了关键技术支撑。

     

    Abstract: Yunnan Province is one of the major macadamia-producing regions in China, where large-scale cultivation under high-altitude ecological conditions has led to frequent off-season flowering and asynchronous flowering within the same tree. These phenomena reduce flowering synchrony, which is detrimental to pollination, fertilisation, fruit set, fruit retention, and uniform harvesting, thereby affecting yield stability and fruit quality. In addition, current flowering regulation practices still rely heavily on manual operations, which are labour-intensive, inefficient, costly, and highly dependent on subjective experience. As a result, traditional regulation approaches can no longer meet the urgent demand for precision-oriented and automated orchard management. To address these challenges and promote intelligent orchard management, this study proposes an intelligent identification method for macadamia inflorescences in natural environments based on an improved YOLO11n object detection model. The proposed model is specifically optimised to cope with several challenges encountered in real orchard environments, including complex background interference, multi-scale morphological variation of inflorescences, partial occlusion, and the constraints of real-time edge deployment. First, a Partial Multi-Scale Feature Aggregation (PMSFA) module is introduced. By integrating partial convolution with multi-scale feature extraction, this module efficiently captures and aggregates multi-source heterogeneous features from different network layers, thereby significantly enhancing the detection of small and easily occluded inflorescences in cluttered natural backgrounds. Second, to balance detection accuracy and computational efficiency, Group-Shuffle Convolution (GSConv) and the Variety of View Group Shuffle Cross-Stage Partial Network (VoV-GSCSP) are incorporated to construct a Slim-neck architecture. This design reduces computational complexity and parameter size while maintaining high detection accuracy, thus improving suitability for edge deployment. Third, in terms of loss function optimization, the original Complete Intersection over Union (CIoU) loss in YOLO11n is replaced with Focaler-PIoU v2. This modification increases the gradient contribution of high-quality samples during training and improves the stability of bounding-box regression, thereby enhancing localization accuracy under challenging conditions such as occlusion and scale variation. Extensive comparative experiments conducted on a dedicated dataset of Yunnan macadamia inflorescences demonstrate that the improved YOLO11n model consistently outperforms several mainstream state-of-the-art object detection methods across all evaluation metrics. Compared with Faster R-CNN, SSD, RT-DETR, YOLOv5s, YOLOv8n, YOLOv10n, and YOLOv12n, the proposed model achieves substantial performance gains. Specifically, Precision increases by 20.1, 5.4, 1.7, 3.5, 3.6, 2.0, and 0.8 percentage points, respectively, while Recall increases by 1.4, 16.2, 8.1, 5.0, 6.4, 9.1, and 6.7 percentage points, respectively. For mean average precision at an IoU threshold of 0.5 (mAP0.5), the proposed model achieves improvements of 6.4, 15.9, 5.7, 4.3, 4.1, 5.0, and 3.3 percentage points, respectively. Under the more stringent mAP0.5–0.95 metric, the corresponding improvements reach 20.1, 33.5, 11.9, 13.5, 10.6, 11.0, and 9.7 percentage points, respectively. These results indicate that the proposed method achieves superior precision, recall, and overall detection accuracy, particularly under complex natural conditions. To further verify the practical feasibility of the proposed method, the improved model is deployed on the Orange Pi AI Pro edge-computing platform. By utilising Neural Processing Unit (NPU)-accelerated inference together with multi-threaded scheduling optimization, the deployed system achieves a real-time detection speed of 72.8 frames per second (FPS), fully satisfying the requirements for accurate and real-time recognition in natural orchard environments. Overall, the results demonstrate that the proposed model achieves a favourable balance among detection accuracy, computational efficiency, and deployment feasibility, and provides strong technical support for the development of intelligent and precise flowering-period regulation equipment for macadamia production in Yunnan Province.

     

/

返回文章
返回