Dynamic Modelling and Experimental Characterization of a Self-Powered Structural Health-Monitoring System with MFC Piezoelectric Patches

Abstract

The paper deals with theoretical and experimental studies for the development of a self-powered structural health monitoring (SHM) system using macro-fiber composite (MFC) patches. The basic idea is to integrate the actuation, sensing, and energy harvesting capabilities of the MFC patches in a SHM system operating in different regimes. As an example, during flight, under the effects of normal structural vibrations, the patches can work as energy harvesters by maintaining or restoring the battery charge of the stand-by SHM electronic board; on the other hand, if relevant/abnormal loadings are applied, or if local faults produce a noticeable stiffness variation of the monitored component, the patches can act as sensors for the power-up SHM board. During maintenance, the patches can then work as actuators, to stress the structure with pre-defined load profiles, as well as sensors, to monitor the structural response. In this paper, the investigation, based on the electromechanical impedance technique, is carried out on a system prototype made of a cantilevered composite laminate with six MFC patches. A high-fidelity nonlinear model of the system, including the piezoelectric hysteresis of the patches and three vibration modes of the laminate beam, is presented and validated with experiments. The results support the potential feasibility of the system, pointing out that the energy storage can be used for recharging a 3V-65mAh Li-ion battery, suitable for low-power electronic boards. The model is finally used to characterize a condition-monitoring algorithm in terms of false alarms rejection and vulnerability to dormant faults, by simulating built-in tests to be performed during maintenance.

Structural Health and Condition Monitoring with Acoustic Emission and Guided Ultrasonic Waves: What about Long-Term Durability of Sensors, Sensor Coupling and Measurement Chain?

“…Due to environmental and health concerns, however, PZT may mandatorily have to be replaced by lead-free alternatives soon [38]. The shapes of the piezoelectric elements and transducers, respectively, comprise, e.g., disks [39] or wafers [40,41]; thin, planar piezoelectric fiber composites, e.g., so-called Active Fiber Composites (AFC) [42,43] or Macro Fiber Composites (MFC) [44,45]; various piezoelectric composites made with piezoelectric powders or particles [35]; piezoceramic thin films [46]; or piezoelectric polymers often also in the form of thin films. The latter are mainly used in high-frequency UT devices, e.g., for medical ultrasound [47,48].…”

Subzero temperatures and low-frequency impact on MFC piezoelectric transducers for wireless sensor applications

“…References [9][10][11][12] highlight the crucial role of piezoelectric transducers in structural health monitoring (SHM) by providing an efficient means of detecting and assessing structural integrity. These transducers, capable of converting mechanical strain into electrical signals and vice versa, offer exceptional sensitivity, compact size, and a wide frequency response.…”

Properties of novel 0–3 PZT/silicone resin flexible piezoelectric composites for ultrasonic guided wave sensor applications

“…PVDF piezoelectric film has advantages of small thickness and high flexibility, but its piezoelectric performance fluctuates greatly at ambient temperatures. Piezoelectric fiber composites are fine diameter piezoelectric fibers evenly arranged in a polymer, such as macro fiber composites (MFC) (Di Rito et al, 2020) and active fiber composites (AFC) (Stepinski et al, 2017). However, their fabrication is complex and their production cost is high, resulting in their limited application.…”