Helicopter Rotor Blade Monitoring using Autonomous Wireless Sensor Network

The advancement on Wireless Sensor Networks for vibration monitoring presents important possibilities for helicopter rotor health and usage monitoring. While main rotor blades account for the main source of lift for helicopters, rotor induced vibration establishes an important source for understanding the rotor performance and blade condition. A discussion on the dual character of blades as rotating structures results in two different interrogation strategies for external and internal dynamic loading on the blade. The first strategy aims for in-flight rotor performance monitoring, while the second pursues health assessment. An overview of different measurements performed on an actual helicopter blade is presented. The measurements include a complete modal analysis using a full wired instrumented blade and a comparison between wireless sensor nodes and wired instrumentation. Additionally, a numerical multibody dynamics model for damage simulation is presented. The experimental and numerical work contribute to the identification of several implications on the migration of condition and health monitoring techniques to a wireless setting.