Surface Ice Detection on Composite Plates with Ultrasonic Guided Waves

The paper presents an integrated active system for ice detection on composite plates with ultrasonic guided waves. The aim is to efficiently detect ice formation and growing on complex structures to ensure safety in transportation vehicles. Ice may lead to serious hazards and its early detection is crucial to avoid catastrophic events. In addition, structural health monitoring based on wave propagation benefits from its early detection preventing misleading interpretation of ultrasound signals. Guided wave propagation, likely adopted for damage monitoring in complex structures, can be likewise adopted to reveal the presence of the ice and characterize its dimension. Experimental tests have been carried out in this work to investigate the effect of an emerging ice layer on wave propagation using the pitch-catch approach. Different measurements have been carried out on a glass fiber composite panel integrated with light piezoelectric actuators. The icing condition is simulated using a climate chamber where water is used to trigger the ice formation. The ultrasonic data have been recorded with a dedicated acquisition system. Results show that reflections generated at the ice location are quite visible in the propagating waves indicating waves as ice sensitive. In addition waterfall diagram and RMS analysis show that ice significantly changes the signals. The outcomes and their post-processing analysis definitely prove the ability of guided waves to detect ice.