基于改进SSD模型的风电叶片内腔缺陷检测

Wind turbine blade internal cavity defect detection algorithm based on improved SSD model

针对风电叶片内腔结构复杂、缺陷种类多样、难以准确检测等问题,提出了改进的单次多边界框检测器(SSD)缺陷检测算法,并提出3方面改进:通过将SSD基础网络由可变形卷积神经网络(VGG-16)变成残差网络(ResNet101)以优化预测边界框的回归和分类任务的输入特征;通过加入全卷积空间注意力模块(FCSE)使模型更加关注重要特征,从而提高检测的准确性;通过在损失函数中添加超参数来控制平滑区域,使模型更加稳定。在自建风电叶片内腔数据集上的对比实验表明,改进的SSD模型平均精度(mAP)值为83.6%,比原始SSD模型提升了9.4个百分点,检测精度优于其他基于SSD框架的主流模型,同时该模型大幅减少了模型参数量,降低了模型的复杂度和存储需求,检测速度为31.6 f/s,可满足实际生产工作中的检测速度需要。

This paper aims to solve the problem of accurate detection of various types of defects in the complex internal cavity structure of wind turbine blades.An improved SSD(single shot multibox detector)algorithm is thus proposed and three aspects of improvement are made:1)in terms of network framework,the base network of SSD is changed from VGG-16 to ResNet101 to optimize the input features for the regression and classification tasks of predicting bounding boxes;2)an FCSE attention module is added to make the model pay more attention to important features and improve its detection accuracy;3)the loss function is improved by adding a hyperparameter to control the smooth region,making the model more robust.Through comparative experiments on a self-built wind turbine blade internal cavity dataset,the improved SSD model achieves an mAP value of 83.6%,which is 9.4 percentage points higher than that of the original SSD model,and has advantages over other mainstream models based on SSD framework in detection accuracy,while greatly reducing the model parameter quantity,lowering the model complexity and storage requirements,and achieving a detection speed of 31.6 f/s,meeting the detection speed needs in practical production.