Uniplexing and Multiplexing of PZT Transducers for Structural Health Monitoring

Abstract

Piezoceramic (PZT) transducers are extensively used in structural health monitoring (SHM) and noise and vibration control (NVC) of various aero, civil, and mechanical (ACM) structures. They are surface bonded on the host structure and are excited to produce structural responses. These responses form the basis of PZT—structure interaction based SHM or NVC methods. The last couple of decades have seen many `single input single output' (SISO) type PZT—structure interaction models. However, researchers are compelled to study `multiple input multiple output' (MIMO) or `multiple input single output' (MISO) type PZT—structure interaction models in addition to the SISO models to deal with ACM structures. Multiplexing is a process of active excitation and extraction of output responses from multiple PZT transducers, whereas uniplexing is active excitation and extraction of output response from a single PZT in the presence of other passive distributed transducers. Thus, this article focuses on the experimental study of such MISO/MIMO based multiplexing of PZT transducers, together with SISO based uniplexing on a prototype plate structure. This study also highlights the problems of interference due to transducers during uniplexing/ multiplexing and their influence on output responses.