Vibration-based Damage Assessment for Controller Reconfiguration: Application to an Oilpan

摘要

One of the objectives of the EU research project InMAR ("Intelligent Materials for Active Noise Reduction") is to reduce car engine noise by active control. An oilpan of a passenger car serves as a demonstrator. A concern in the application of active control is that the controlled system may change during service life (e.g. due to damage), and hence, may degrade the control performance. This paper presents two vibration-based methods that are able to autonomously detect damage and yield updated experimental models of the structure. A first approach is based on (operational) modal analysis. Based on vibration measurements, the modal parameters of the structure are estimated. The idea is now to automate this process so that, without human intervention, a representative dynamic model of the structure is always available. A second approach uses multiple-model estimation in the case when the state-space models have different state dimensions. To this end, an existing non-interacting multiple-model estimator has been extended to make it alert to jumps from one model to another. Both techniques ("Automatic Modal Analysis" and "Alert Autonomous Multiple Model Estimator") will be applied to experimental vibration data from an oilpan of a passenger car subjected to damage (loosening of bolts).