Application of Wavelet Transform for Analyzing Instantaneous Contour of Continual Deformation Object

Abstract

The reconstruction of instantaneous contour is a common method to analyze the kinetic characteristic of a continual deformation object. In this paper a continuous wavelet transform method (CWT) is applied to analyze the instantaneous contour of a continual deformation object based on shadow moiré technique. The modulated moiré fringe patterns are captured by use of a high-speed CCD camera and the temporal intensity variation of each pixel related to the object deformations is recorded. The intensity variation of each pixel is analyzed along the time axis by CWT. From the extraction of the ridges and from the value of the CWT along the ridges, the information of modulated phase relative to the contour of object can be obtained. In this application, a cantilever beam with a motion in the Z direction is tested by use of the method and the high-quality instantaneous contour of the continual deformation object can be retrieved. Experimental results prove that the CWT can successfully be applied to the instantaneous contour analysis of continual deformation object and these results demonstrate the advantages of the CWT with respect to the applicable simplicity and the resistance of noise pollution.