Fig. 9: Model cross-training applying limited portions of the experimental slip cycle.

Two models are trained and in both cases only the latent space is trained using data from experiment p4677 applying the following criteria. One model is trained applying acoustic emission (AE) data from the post-failure portion of the slip cycle, comprising the time-period when the shear stress is increasing relatively rapidly. The second model is trained applying AE data from the pre-failure period comprising the period the fault is in a critical state and nucleating. The model encoder and decoder trained applying the simulation data remain unchanged. Friction predictions on data from the experiment p4581 testing data set for pre-failure at applied loads of 3, 5, and 7 MPa are shown in each top row of (a–c) shown in light blue and post-failure in each bottom row of (a, b, c) shown in light green. The shading of the panels correspond to the portion of training data highlighted in Fig. 8. The mean absolute percentage error (MAPE) is shown for each respective load level and model.