A wireless piezoelectric sensor network for distributed structural health monitoring

This paper presents the development of a newly designed wireless piezoelectric (PZT) sensor platform for distributed active structure health monitoring (such as aircraft wings and bridges). The developed wireless PZT-sensor network features real-time data acquisition with high sampling rate up to 12.5MSPS (sample per second), distributed lamb-wave data processing and energy saving by reducing the amount of data in wireless transmission. In the proposed wireless PZT network, a set of PZT transducers deployed at the surface of the structure, and a lamb wave is excited and its propagation characteristics within the structure are inspected to identify possible damages. The developed wireless node platform benefits from a digital signal processor (DSP) of TMS320F28335 and an improved IEEE 802.15.4 wireless data transducer RF233 with up to 2Mbps data rate. Each node supports up to 8 PZT transducers, one of which may work as the actuator generating the Lamb wave at an arbitrary frequency, while the responding vibrations at other PZT sensors are sensed simultaneously. In addition to hardware, embedded signal processing and distributed data processing algorithm are designed as the intelligent `brain´ of the proposed wireless monitoring network to extract features of the PZT signals, so that the data transmitted over the wireless link can be reduced significantly.