3-D Vibration Measurement Using a Single Laser Scanning Vibrometer by Moving to Three Different Locations

3-D vibration measurement is achieved using a single laser scanning vibrometer (LSV) and laser scanner (LS) by moving them to three arbitrarily different locations from the principle that vibration analysis based on the frequency domain is independent of the vibration signal based on time domain. The proposed system has the same effect as using three sets of LSVs, and has an advantage of reducing equipment costs. Analytical approach of obtaining in-plane and out-of-plane vibration of surface is introduced using geometrical relations between three LSV coordinates and vibrations measured at three different locations. The proposed algorithm is verified by comparing the experimental results obtained by a three-axis accelerometer and a developed optical system with an LSV and an LS combined together.