Localization of breathing cracks using combination tone nonlinear response

Abstract

In this paper, a new nonlinear combination tone system identification technique isinvestigated to identify breathing crack damage in isotropic rod structures. Inspired by thecombination tone phenomenon observed in the human auditory system, the difference oftwo harmonic excitation frequencies is utilized to detect and locate the breathing crack.The method of multiple scales is used to analyze a simplified but representative bilinearsystem and gain insight into the concept. An experimental investigation is performed toverify the proposed approach. Compared to previously introduced techniques for nonlinearsystem identification of breathing cracks using super-harmonic or sub-harmonicsignals, the proposed approach is much more robust and easier to implement.