Real-time and anti-noise fault diagnosis algorithm based on 1-D convolutional neural network

A novel one-dimensional (1-D) convolutional neural network (CNN) was proposed based on the classic model LeNet-5, aiming at problems of high computational complexity and low anti-noise ability toward rotating machinery intelligent diagnosis: (1) It adopts global average pooling layer instead of fully connected layers in the conventional CNNs, which reduces the computational complexity, model parameters and risk of overfitting, (2) It is trained with randomly dropout raw signals for anti-noise purpose and (3) It uses modified 1-D convolutional and pooling filters, which works directly on raw time-domain signals, fusing two stages of fault diagnosis into a single learning body, feature learning by the alternating convolutional and pooling layers while classification by the global average pooling layer. The bearing data and gearbox data are used in experimental verification and the classic models of LeNet-5, BP neural network and SVM are used as comparison. The results show that the adoption of global average pooling layers can reduce the model computation and improve the diagnostic accuracy under low signal-to-noise (SNR) conditions, and the train strategy of randomly dropout input can significantly improve the anti-noise ability of the model. As a result, the proposed model can realize accurate, fast and robust fault diagnosis under noisy environment. At last, the t-SNE visualization analysis is used to validate the feature learning ability of the proposed model. © 2019, Editorial Board of Journal of Harbin Institute of Technology. All right reserved.