Abstract
This paper describes a bolt loosening detection by a spatial filtering in low frequency region of a few of kilohertz. The spatial filter can be realized using a number of sensors attached to a structure that is less than the number of target modes. The authors have been verified a feasibility of a monitoring methodology for monitoring health and detecting structural damage using spatial filtering. In this study, the loosening of the bolt tightening torques is defined as structural damage of the system. The spatial filter is detected the damage by evaluation of filtered responses in vibration testing of fixed end plate structure.
