A LSTM Neural Network Approach using Vibration Signals for Classifying Faults in a Gearbox

A deep learning based method for classifying multi-class faults in a gearbox is presented. A set of 900 vibration signals representing the normal condition and nine faults comprises the dataset used in this research. The recorded vibration signals are pre-processed for extracting the first and second derivatives as well as the first five Intrinsic Mode Functions (IMFs) by applying the Empirical Mode Decomposition (EMD) method. A 2D representation of these signals is the feature space used for classifying ten conditions of a gearbox using a Long Short Term Memory (LSTM) neural network. The 2D feature space is subdivided along the temporal axis in segments of the same size as the LSTM network. These segments are classified and a voting systems is proposed for attaining the signal classification. A 10-fold cross-validation is used for evaluating the proposed deep learning model. An average accuracy up to 99.4 % for classifying the faults is attained during the cross-validation.