Crack recognition approach assisted by three-dimensional measurement technique

In traditional crack recognition, most methods are based on a two-dimensional plane to recognize crack. However, crack like objects or textures can easily lead to crack recognition errors. In this paper, we adopt fringe projection three-dimensional (3D) measurement technique to assist in crack recognition. Firstly, we briefly introduce crack recognition based on traditional wavelet transform (WT) and analyze its drawbacks. Then, we introduce a fringe projection phase extraction method and a phase–height-calibration method. Finally, traditional crack recognition and 3D measurement assisted crack recognition are compared through experiments. The experimental results confirm that 3D measurement-assisted crack recognition is more accurate than the traditional crack recognition.