EMI Based Cable Force Monitoring Using the Piezoelectric Ceramic Transducers

The electromechanical impedance (EMI) method based on piezoelectric ceramics has the advantages of simple operation, fast detection speed, high recognition accuracy, and wide application range. Due to its advantages, monitoring technology based on the EMI method using piezoelectric ceramic transducers has attracted more and more attention in recent years. In this paper, aiming at the problem of cable force loss, the piezoelectric ceramic transducers were coupled to the surface of the end anchor nut/plate and the EMI method was used to investigate the relationship between the impedance and the cable force. Two types of cable anchors under six levels of load were investigated. The results showed that the PZT transducer with copper shell can well shield the surrounding electromagnetic signal interference. The peak of the impedance curve shifted to the higher frequency with the increase of the force. The normalized root mean square deviation (RMSD) value can well represent the level of the cable force.