The development of an active sensing node has brought the traditional impedance-based structural health monitoring (SHM)
technique to a new paradigm. The active sensing node consists of a miniaturized impedance measuring device (AD5933), a
microcontroller (ATmega128L), and a radio frequency (RF) transmitter (XBee). A macro-fiber composite (MFC) patch
interrogates a host structure by using a self-sensing technique of the miniaturized impedance measuring device. All the process
including structural interrogation, data acquisition, signal processing, and damage diagnostic is being performed at the sensor
location by the microcontroller. The RF transmitter is used to communicate the current status of the host structure. To validate
the feasibility of the proposed active sensor node, two kinds of example studies are carried out: (a) corrosion detection on an
aluminum beam and (b) loose bolt inspection on a bolt-jointed structure.