Low-Power Design and Critical Event-Triggered Transmission Scheme for Wireless Strain Gauge Sensor Node in Aircraft Structural Health Monitoring

The development of wireless sensor network integrated into aircraft structural health monitoring (SHM) can help to achieve the goal of deploying more sensors for the significant benefits in flexibility, interoperability, mass reduction, system redundancy and enhanced robustness. The objective of this paper is research and development concerning wireless strain gauge sensor node mounted on aircraft, towards prolonging the battery lifetime and balancing the power-performance tradeoff. This wireless sensor node can acquire the strain in a structure, convert, conditioning, process and finally transmit data by wireless connection. This wireless sensor node included mainly a nonlinear bridge strain transducer, bridge sensor conditioner, lookup table, low pass filter, ADC, MCU, low-power RF transceiver, external memory, RTC, energy harvesting, energy storage and management. The functions, considerations and specifications of these main parts were described. A low-power design and a critical event-triggered transmission scheme were illustrated and applied to reduce power consumption and conserve network bandwidth. The experimental results show that this wireless strain gauge sensor node is reasonable potential for aircraft SHM