Impact Damage Detection Using Chirp Ultrasonic Guided Waves for Development of Health Monitoring System for CFRP Mobility Structures

• Published in: Sensors (Basel, Switzerland) Vol. 22; no. 3; p. 789
• Main Authors: Tan, Langxing, Saito, Osamu, Yu, Fengming, Okabe, Yoji, Kondoh, Taku, Tezuka, Shota, Chiba, Akihiro
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 20.01.2022; MDPI
• Subjects: Broadband; Carbon Fiber; Carbon fiber reinforced plastics; carbon fiber-reinforced plastic (CFRP); chirp signal; Chirp signals; Cracks; Damage detection; Data processing; Herbivores; Impact damage; Lamb waves; Laminates; Mechanical properties; Piezoelectric actuators; Plastics; Structural health monitoring; Ultrasonic Waves; Ultrasonics; Wave propagation; Japan; Lamb waves; impact damage; chirp signal; structural health monitoring; carbon fiber-reinforced plastic (CFRP)
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s22030789

When impact damage occurs in carbon fiber-reinforced plastic (CFRP) structures, it is barely visible but may cause significant degradation in the mechanical properties of the structure. Hence, a structural health monitoring (SHM) system that can be installed in CFRP mobility structures and is sensitive to impact damage is needed. In this study, we attempted to establish an SHM system based on ultrasonic guided waves, which are generated by inputting a broadband chirp signal into a film-like piezoelectric actuator. The relationship between impact damage size and maximum time-of-flight (ToF) delay was investigated for three types of CFRP plates: woven, non-woven, and hybrid laminates. As a result, it was found that the maximum ToF delay increased linearly with an increase in the damage size for all CFRP laminates. Moreover, the amplitude of the A mode was found to be significantly affected by the damage length in the wave propagation direction. Thus, this SHM method using chirp ultrasonic waves can quantitatively evaluate the size and extent of the impact damage in CFRP laminates.