This study aimed to address the challenge of accurately and reliably detecting tomatoes in dense planting environments,a critical prerequisite for the automation implementation of robotic harvesting.However,the heavy ...This study aimed to address the challenge of accurately and reliably detecting tomatoes in dense planting environments,a critical prerequisite for the automation implementation of robotic harvesting.However,the heavy reliance on extensive manually annotated datasets for training deep learning models still poses significant limitations to their application in real-world agricultural production environments.To overcome these limitations,we employed domain adaptive learning approach combined with the YOLOv5 model to develop a novel tomato detection model called as TDA-YOLO(tomato detection domain adaptation).We designated the normal illumination scenes in dense planting environments as the source domain and utilized various other illumination scenes as the target domain.To construct bridge mechanism between source and target domains,neural preset for color style transfer is introduced to generate a pseudo-dataset,which served to deal with domain discrepancy.Furthermore,this study combines the semi-supervised learning method to enable the model to extract domain-invariant features more fully,and uses knowledge distillation to improve the model's ability to adapt to the target domain.Additionally,for purpose of promoting inference speed and low computational demand,the lightweight FasterNet network was integrated into the YOLOv5's C3 module,creating a modified C3_Faster module.The experimental results demonstrated that the proposed TDA-YOLO model significantly outperformed original YOLOv5s model,achieving a mAP(mean average precision)of 96.80%for tomato detection across diverse scenarios in dense planting environments,increasing by 7.19 percentage points;Compared with the latest YOLOv8 and YOLOv9,it is also 2.17 and 1.19 percentage points higher,respectively.The model's average detection time per image was an impressive 15 milliseconds,with a FLOPs(floating point operations per second)count of 13.8 G.After acceleration processing,the detection accuracy of the TDA-YOLO model on the Jetson Xavier NX development board is 90.95%,the mAP value is 91.35%,and the detection time of each image is 21 ms,which can still meet the requirements of real-time detection of tomatoes in dense planting environment.The experimental results show that the proposed TDA-YOLO model can accurately and quickly detect tomatoes in dense planting environment,and at the same time avoid the use of a large number of annotated data,which provides technical support for the development of automatic harvesting systems for tomatoes and other fruits.展开更多
本实验针对马铃薯干腐病潜育期到发病期的诊断方法进行研究,利用时序高光谱对病害发生过程中的病症特征进行分析和提取,并基于时序性特征采用动态时间弯曲(dynamic time warping,DTW)聚类算法对时序关键点进行分析,即对发病期初始点进...本实验针对马铃薯干腐病潜育期到发病期的诊断方法进行研究,利用时序高光谱对病害发生过程中的病症特征进行分析和提取,并基于时序性特征采用动态时间弯曲(dynamic time warping,DTW)聚类算法对时序关键点进行分析,即对发病期初始点进行诊断。本研究在数据预处理中使用图像阈值分割算法提取动态感兴趣区域,利用概率密度比算法剔除病害光谱异常值,在对比病症的光谱与外观后,发现马铃薯干腐病的光谱具有非单调性特征,再基于该非单调性特征使用高斯核函数的主成分权重系数法进行光谱特征提取。最后基于病害特征,利用模糊聚类方法判定时序关键点,其结果正确率仅为66.7%;针对特征时序性再利用DTW聚类算法判定时序关键点,其结果正确率达94.4%。本实验研究表明基于DTW的时序高光谱诊断方法能对马铃薯干腐病发病期进行有效诊断。展开更多
基金The National Natural Science Foundation of China (32371993)The Natural Science Research Key Project of Anhui Provincial University(2022AH040125&2023AH040135)The Key Research and Development Plan of Anhui Province (202204c06020022&2023n06020057)。
文摘This study aimed to address the challenge of accurately and reliably detecting tomatoes in dense planting environments,a critical prerequisite for the automation implementation of robotic harvesting.However,the heavy reliance on extensive manually annotated datasets for training deep learning models still poses significant limitations to their application in real-world agricultural production environments.To overcome these limitations,we employed domain adaptive learning approach combined with the YOLOv5 model to develop a novel tomato detection model called as TDA-YOLO(tomato detection domain adaptation).We designated the normal illumination scenes in dense planting environments as the source domain and utilized various other illumination scenes as the target domain.To construct bridge mechanism between source and target domains,neural preset for color style transfer is introduced to generate a pseudo-dataset,which served to deal with domain discrepancy.Furthermore,this study combines the semi-supervised learning method to enable the model to extract domain-invariant features more fully,and uses knowledge distillation to improve the model's ability to adapt to the target domain.Additionally,for purpose of promoting inference speed and low computational demand,the lightweight FasterNet network was integrated into the YOLOv5's C3 module,creating a modified C3_Faster module.The experimental results demonstrated that the proposed TDA-YOLO model significantly outperformed original YOLOv5s model,achieving a mAP(mean average precision)of 96.80%for tomato detection across diverse scenarios in dense planting environments,increasing by 7.19 percentage points;Compared with the latest YOLOv8 and YOLOv9,it is also 2.17 and 1.19 percentage points higher,respectively.The model's average detection time per image was an impressive 15 milliseconds,with a FLOPs(floating point operations per second)count of 13.8 G.After acceleration processing,the detection accuracy of the TDA-YOLO model on the Jetson Xavier NX development board is 90.95%,the mAP value is 91.35%,and the detection time of each image is 21 ms,which can still meet the requirements of real-time detection of tomatoes in dense planting environment.The experimental results show that the proposed TDA-YOLO model can accurately and quickly detect tomatoes in dense planting environment,and at the same time avoid the use of a large number of annotated data,which provides technical support for the development of automatic harvesting systems for tomatoes and other fruits.
文摘本实验针对马铃薯干腐病潜育期到发病期的诊断方法进行研究,利用时序高光谱对病害发生过程中的病症特征进行分析和提取,并基于时序性特征采用动态时间弯曲(dynamic time warping,DTW)聚类算法对时序关键点进行分析,即对发病期初始点进行诊断。本研究在数据预处理中使用图像阈值分割算法提取动态感兴趣区域,利用概率密度比算法剔除病害光谱异常值,在对比病症的光谱与外观后,发现马铃薯干腐病的光谱具有非单调性特征,再基于该非单调性特征使用高斯核函数的主成分权重系数法进行光谱特征提取。最后基于病害特征,利用模糊聚类方法判定时序关键点,其结果正确率仅为66.7%;针对特征时序性再利用DTW聚类算法判定时序关键点,其结果正确率达94.4%。本实验研究表明基于DTW的时序高光谱诊断方法能对马铃薯干腐病发病期进行有效诊断。