Wan Min, Xiao Yujie, Zhang Jingran
School of Mechatronic Engineering, Southwest Petroleum University, Chengdu 610500, China.
Rev Sci Instrum. 2024 Apr 1;95(4). doi: 10.1063/5.0192639.
Traditional approaches to the intelligent fault diagnosis of rolling bearings have predominantly relied on manual expertise for feature extraction, a practice that compromises robustness. In addition, the existing convolutional neural network (CNN) is characterized by an overabundance of parameters and a substantial requirement for training samples. To address these limitations, this study introduces a novel fault diagnosis algorithm for rolling bearings, integrating a one-dimensional convolutional neural network (1DCNN) with a support vector machine (SVM) to form an enhanced 1DCNN-SVM model. This model is further refined using the sparrow search algorithm (SSA) for the optimal adjustment of the parameters of 1DCNN-SVM. Specifically, by substituting the CNN's final softmax layer with an SVM, the model becomes better suited for processing limited data volumes. In addition, the incorporation of batch normalization and dropout layers within the CNN framework significantly augments its fault classification accuracy for rolling bearings, concurrently mitigating the risk of overfitting. The SSA is subsequently applied to refine three principal hyper-parameters: batch size, initial learning rate, and the L2 regularization coefficient, thereby overcoming the challenges associated with manually adjusting parameters, such as extended processing times and unpredictable outcomes. Empirical tests on Case Western Reserve University (CWRU) datasets revealed the model's superior performance, with the SSA-optimized 1DCNN-SVM showcasing diagnostic accuracies over 98%, marked improvements over conventional models, and a significant reduction in processing times. This method not only marks a significant advancement in intelligent fault diagnosis for rolling bearings but also demonstrates the potential of integrating machine learning for more precise and efficient diagnostics. The SSA-1DCNN-SVM model, optimized for accuracy and minimal data use, sets a new standard in fault diagnosis, relevant for machinery health monitoring and maintenance strategies across various industries.
传统的滚动轴承智能故障诊断方法主要依靠人工专业知识进行特征提取,这种做法会影响诊断的稳健性。此外,现有的卷积神经网络(CNN)存在参数过多以及对训练样本需求量大的问题。为解决这些局限性,本研究引入了一种用于滚动轴承的新型故障诊断算法,将一维卷积神经网络(1DCNN)与支持向量机(SVM)相结合,形成增强型1DCNN-SVM模型。使用麻雀搜索算法(SSA)对该模型进行进一步优化,以实现对1DCNN-SVM参数的最优调整。具体而言,通过用SVM替代CNN的最终softmax层,该模型更适合处理有限的数据量。此外,在CNN框架中加入批量归一化和随机失活层,显著提高了其对滚动轴承的故障分类准确率,同时降低了过拟合风险。随后应用SSA对三个主要超参数进行优化:批量大小、初始学习率和L2正则化系数,从而克服了手动调整参数带来的挑战,如处理时间长和结果不可预测等问题。在凯斯西储大学(CWRU)数据集上的实证测试表明了该模型的卓越性能,经SSA优化的1DCNN-SVM的诊断准确率超过98%,比传统模型有显著提高,且处理时间大幅减少。该方法不仅标志着滚动轴承智能故障诊断取得了重大进展,还展示了集成机器学习实现更精确高效诊断的潜力。针对准确性和最小数据使用进行优化的SSA-1DCNN-SVM模型为故障诊断树立了新的标准,适用于各行业的机械健康监测和维护策略。