Strain distribution monitoring wireless sensor network design and its evaluation research on aircraft wingbox

This paper presents a dedicated wireless sensor node for strain distribution monitoring, three functional modules are designed respectively, including sensor input unit, processing core, and wireless communication. The multi-channel strain gauge signal conditioning circuit is designed on the sensor input unit for multi-point strain distribution monitoring requirement and proved to be accurate and reliable. A miniature, lightweight, and shock-proof aluminum encapsulation is also designed especially for aerospace structural health monitoring (SHM) application. To verify the functionality of the designed wireless sensor node for SHM capability, a multi-point strain distribution monitoring system is developed on a aircraft carbon fiber reinforced plastic (CFRP) wing box. The strain gauges array is stuck to the inner surface of the CFRP wainscot and used to monitoring multi-point strain distribution. The reliable wireless sensor network is deployed adopting the designed wireless sensor nodes to gather, process, and transmit strain gauges signals and monitoring results. An embedding pattern matching method and a directed diffusion routing algorithm are developed to monitor the strain distribution successfully for the actual big CFRP wainscot.