Prediction method of RUL of bearings in GRU network based on Bayesian optimization
The traditional model for predicting the remaining service life of rolling bearings faces difficulties in parameter optimization.To address this issue,a Bayesian optimization based GRU network method for predicting the remaining service life of rolling bearings was proposed and experimentally validated.Taking the PHM2012 dataset as an example,the Bayesian optimization algorithm was used to optimize multiple hyperparameters of the Encoder Decoder based Gated Recurrent Unit(GRU)prediction model.First,the original data containing noise was subjected to wavelet packet processing.From the vibration mechanism and fault characteristics of rolling bearings,time-domain features were extracted.The extracted time-domain features were optimized and selected,and then input into the encoder part of the model to further extract deeper temporal features.Then,by integrating attention mechanism with the Encoder-Decoder structure,a bidirectional GRU neural network model was constructed.The Bayesian optimization method was employed to search in the high-dimensional hyperparameter space of the model.The optimal hyperparameter combination was gained.Linear transformation was incorporated into the decoder.The predicted remaining service life of the rolling bearings was gained.Finally,the entire process of model construction,training,and usage was encapsulated.A rolling bearing residual service life prediction workflow based on Bayesian optimization of the GRU network was established.The effectiveness of the method was validated through comparative experiments.The research results indicate that the GRU network based on Bayesian optimization can effectively predict the residual service life of rolling bearings.Comparing to the optimal results of the other three methods,the average prediction score of the GRU network based on Bayesian optimization improves by 8.01％.The GRU network based on Bayesian optimization demonstrates accurate predictions for rolling bearings with shorter life.For bearings with longer life,the predicted values do not exceed the real values.Therefore,it can serve as a reference for remaining useful life estimation in the approaching failure stage of the bearings.
万方数据
维普
