Development of microcontroller based multipurpose wireless edge node for integrated structural health monitoring

Abstract

Usage of composite materials for lightweight aircraft structures have increased interest in monitoring of structural loading and in detection of damages. Demands for replacement of conventional structural health monitoring devices to a more compact and lightweight measurement devices are growing. In this thesis, a study on microcontroller based edge node for structural health monitoring was conducted to increase the adaptability of structural health monitoring in aircraft structures. Wireless strain device (WSD) was capable of measuring low frequency loadings and high frequency impacts from strain gauges through long range wireless transmission. Also, strain measurements during temperature change were conducted for the temperature compensation calculations in order to increase the adaptability for varying temperature environments. Wireless ultrasonic device (WUD) was capable of ultrasonic measurements through fast measurement speed and high wireless data transmission rate. Wireless ultrasonic measurements with piezoelectric ceramic transducers were conducted through pitch-catch method for simultaneous sensing and actuation through WUD. Also, wireless ultrasonic measurements during temperature change were investigated for temperature compensation Pencil-lead breakage test for the wireless measurement of acoustic emission and wireless G-UPI for laser induced ultrasonic wireless measurements were conducted through WUD. Adaptability of WUD was shown through multipurpose ultrasonic measurements for complex structural health monitoring. Therefore, WSD and WUD showed the adaptability for a small sized microcontroller based multipurpose wireless edge node for integrated structural health monitoring in aircraft structures, which would increase the safety of aircraft operations.