Automation in Structural Health Monitoring Using Laser Doppler Vibrometer

This paper presents the development of an automated structural health monitoring strategy based on structural dynamic response over a wide range of frequency. A piezoceramic actuator is used to excite the structure for low frequency vibration modes as well as guided wave propagation studies. A quantifiable measure of damage is defined based on ratios of distributed strain energy between the damaged and undamaged states of the structure. The knowledge of the undamaged structure is synthesized by spatial decimation of measured responses of the structure in its current state. First, a quick assessment is made by measuring low frequency vibration modes over a coarse grid set to determine the presence and general location of damage followed by high frequency guided wave inspection using detailed grid set over the suspect region to characterize the damage. The automation features of the developed technique have been demonstrated on a plate-like structure.

[1]  H. Yim,et al.  Numerical simulation and visualization of elastic waves using mass-spring lattice model. , 2000, IEEE transactions on ultrasonics, ferroelectrics, and frequency control.

[2]  Charles R. Farrar,et al.  Damage identification and health monitoring of structural and mechanical systems from changes in their vibration characteristics: A literature review , 1996 .

[3]  Christian Boller,et al.  Health Monitoring of Aerospace Structures , 2003 .

[4]  Joseph L. Rose,et al.  A Baseline and Vision of Ultrasonic Guided Wave Inspection Potential , 2002 .

[5]  Massimo Ruzzene,et al.  Perturbation methods for the analysis of the dynamic behavior of damaged plates , 2006 .

[6]  Wahyu Lestari,et al.  Damage of composite structures :detection technique, dynamic response and residual strength , 2001 .

[7]  Charles R. Farrar,et al.  Application of the strain energy damage detection method to plate-like structures , 1999 .

[8]  Sathya Hanagud,et al.  An integral equation for changes in the structural dynamics characteristics of damaged structures , 1997 .

[9]  Arun Kumar Pandey,et al.  Damage detection from changes in curvature mode shapes , 1991 .

[10]  Wei Zhao,et al.  Piezoelectric wafer active sensor embedded ultrasonics in beams and plates , 2003 .

[11]  Scott D. Sommerfeldt,et al.  Spatially Continuous Power Flow Using a Scanning Laser Doppler Vibrometer , 2002 .

[12]  Massimo Ruzzene,et al.  Frequency–wavenumber domain filtering for improved damage visualization , 2007 .

[13]  Massimo Ruzzene,et al.  Damage Index Estimation in Beams and Plates Using Laser Vibrometry , 2006 .