Fusion of rotation and translation measurements to improve mass identification in beam structures

Abstract

Mass identification of vibrating structures is part of complex and often numerically inefficient inverse problems of structural dynamics. This paper investigates the application of novel rotation rate sensors to improve experimental mass identifications in rod structures. For this purpose, translational and rotational vibration measurements are used in the modal analyses and the model updating techniques. Numerical simulations were conducted with various added mass configurations investigated, followed by an extensive experimental campaign on a steel beam in free-free conditions. It is demonstrated that including the rotational degrees of freedom in the model updating technique dramatically improves the effectiveness of mass localisation and quantification. This positive effect is particularly pronounced when a limited number of modes is available from modal extraction.