基于Hough变换圆检测原理研发了非接触性动态位移测试方法,采用振动台进行了应用验证.结果表明,Hough变换具有良好的圆检测效果.图像计算效率与角度、半径的检测步长的选取相关;选取较大半径检测步长时,图像处理速度将大幅提高;选取较大角度检测步长时,图像处理速度提高并不显著.通过不同试验验证了自行研发的非接触性位移测试方法在不同频率正弦波输入、图像中不同半径标靶圆及相机.标靶不同物像空间距离特性条件下均具有良好的识别效果.工程实用角度,非接触性位移测试方法可以同时捕捉多个测点的位移及有效解决测试量程受限的问题,并可避免由于接触对被测体产生的干扰.
Non-contact displacement test method Hough transform, which was verified by the was proposed based on shaking table test. The the circle detection using verification results showed that Hough transform had a good performance on the circle detection. The computation efficiency on the images depended on the selected detection steps of the angle and radius. The processing speed of images increased sharply when a larger detection radius step was selected, however, the processing speed increased slightly when a larger detection angle step was adopted. The independently-developed non-contact displacement test method was verified under different testing conditions, considering the input sine wave with different frequencies, the target circle with different radius, and different camera-target distances. The results showed that the proposed method had a good recognition performance. Non-contact displacement test method can capture the displacement of several gauge points at the same time and effectively solve the problem of limited test range, moreover, it can avoid the interference to the measured objects.