Ultrasonic guided-wave damage detection based on CEEMD and improved energy spectrum entropy: application to cortical bone

Pathological fractures, especially those classified as incomplete fractures, are a significant global health issue. Ultrasonic guided wave (UGW) technology is increasingly recognised for its pivotal role in the early detection and diagnosis of fracture injuries. This paper proposes a novel method for UGW-based damage detection in cortical bone, leveraging both the complete ensemble empirical mode decomposition (CEEMD) and an improved energy spectrum entropy (IESE). The UGW signals captured from the cortical bone are decomposed into intrinsic mode functions (IMFs) to capture the damage-induced features and improve the signal-to-noise ratio. By calculating the IESE to measure the complexity and irregularity of UGW signal and reflect signal’s changes caused by injuries, the Pauta criterion is used to determine the damage status of cortical bone. To validate the effectiveness of the proposed method, three types of experiments are conducted on cortical bone samples with artificial damages. The results indicate that the proposed method is effective in detecting cortical bone injuries, with a higher detection accuracy rate of over 93% and sensitivity compared to traditional methods. This study provides a new idea and method for clinical bone damage assessment and holds significant theoretical value and clinical application prospects.