Development of a non-contact PZT excitation and sensing technology via laser

In recent years, guided wave based structural health monitoring (SHM) techniques have attracted much attention, because they are not only sensitive to small defects but also capable to cover a wide range in plate and pipe like structures. The guided waves in a structure can be generated and sensed by a variety of techniques. This study proposes a new wireless scheme for PZT excitation and sensing where power as well as data can be transmitted via laser. A generated waveform by modulation of a laser is wirelessly transmitted to a photodiode connected to a PZT on the structures. Then, the photodiode converts the light into an electrical signal and excite the PZT and the structure. Then, the reflected response signal received at the sensing PZT is re-converted into a laser, which is wirelessly transmitted back to another photodiode located in the data acquisition unit for damage diagnosis. The feasibility of the proposed power and data transmission scheme has been experimentally investigated in a laboratory setup. Using the proposed technology, a PZT transducer can be attached to a structure without complex electronic components and a power supply.

[1]  S. Kasap.  Optoelectronics and Photonics: Principles and Practices , 2001 .

[2]  Gyuhae Park,et al.  Development of an impedance-based wireless sensor node for structural health monitoring , 2007 .

[3]  Hoon Sohn,et al.  Instantaneous reference-free crack detection based on polarization characteristics of piezoelectric materials , 2007 .

[4]  J. R. Wilson,et al.  Optoelectronics, an introduction , 1984 .

[5]  Carlos E. S. Cesnik,et al.  Review of guided-wave structural health monitoring , 2007 .

[6]  Eric M. Yeatman.  Energy harvesting: small scale energy production from ambient sources , 2009, Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[7]  Hoon Sohn,et al.  Wavelet-based active sensing for delamination detection in composite structures , 2004 .

[8]  Fabrizio Scarpa,et al.  Structural health monitoring using scanning laser vibrometry: I. Lamb wave sensing , 2004 .

[9]  Jerome P. Lynch,et al.  Real-time structural damage detection using wireless sensing and monitoring system , 2008 .

[10]  L. Drain,et al.  Laser Ultrasonics Techniques and Applications , 1990 .

[11]  Jerome P. Lynch,et al.  A summary review of wireless sensors and sensor networks for structural health monitoring , 2006 .

[12]  Emmanuel Moulin,et al.  Piezoelectric transducer embedded in a composite plate: Application to Lamb wave generation , 1997 .

[13]  M. Çelebi.  Seismic instrumentation of buildings , 2000 .

[14]  Lei Wang,et al.  Active damage localization technique based on energy propagation of Lamb waves , 2007 .

[15]  H.M.S. Georgiou,et al.  Experimental and theoretical assessment of PZT modeled as RC circuit subject to variable voltage excitations , 2004 .

[16]  Jerald G. Graeme,et al.  Amplifier Applications of Op Amps , 1999 .

[17]  Matt Clark,et al.  Frequency control in laser ultrasound with computer generated holography , 1998 .

[18]  Brian Culshaw,et al.  Non-contact measurement of the mechanical properties of materials using an all-optical technique , 2003 .