Sensor placement for modal identification

Planning of sensor placement can be done by using a finite element model before a modal test. In this paper, a method is proposed in order to select the most relevant degrees of freedom which should be monitored by sensors. It uses two criteria based on observability of mode shapes and on information shared by sensors. A set of sensors is obtained by maximizing the norm of a Fisher information matrix and by avoiding the redundancy of information between the selected degrees of freedom. As this method is mainly devoted to analysis of large finite element models, a fast sensor expansion algorithm provides sub-optimal sets. (C) 2011 Elsevier Ltd. All rights reserved.