连续振动悬臂梁的瞬时三维形貌测量

Instantaneous Three-Dimensional Profile Measurement of Continually Vibrating Cantilever Beam

提出一种连续振动悬臂梁瞬时三维形貌的测量方法。利用影栅云纹法在连续振动悬臂梁表面产生包含有三维形貌信息的云纹,采用准直双光源提高亮度,通过高速摄相机获取随时间变化的一系列变形条纹,利用傅里叶变换方法对序列图像进行处理,采用补零延拓法对数据进行处理,以减小频谱泄漏所引起的相位计算误差。将相位解包裹方法用于动态过程瞬时三维相位场的相位展开中,重建了悬臂梁的瞬时三维形貌,再现了悬臂梁的连续振动过程。

A method for instantaneous three-dimensional profile measurement of a continually vibrating cantilever beam is proposed. The moiré fringes containing the three-dimensional patterns information of a continually vibrating cantilever beam, generated by the interference of the grating lines and their shadows, are captured by a high-speed CCD camera. Two light sources are used to enhance the illumination of the fringe patterns. Fourier transform method is adopted to analyze the time-sequence fringe patterns, and the outer extended interpolation is used to decline the phase error resulting from the leakage of the frequency. The phase unwrapping method is used to unwrap the phase in the dynamic process, the instantaneous three-dimensional profile is obtained and the continually vibrating process of the cantilever beam is reconstructed.