Research on clearance detection method of safety mechanism of Three Gorges ship lift based on machine vision

In view of the current situation of low efficiency, poor accuracy and inability to realize real-time detection of the clearance between the safety mechanism of the Three Gorges ship lift and the thread pair of the nut column, based on the machine vision detection technology, the data acquisition, camera calibration, thread edge line detection and nut column corner detection steps are adopted in turn. The pixel height difference is calculated by using the two midpoints in the image, and the midpoint position of the parallel line segment between the thread surface and the nut column is obtained. According to the camera imaging principle, the actual height difference is calculated to realize the real-time detection of the clearance between the safety mechanism and the thread pair of the nut column, the test shows that the error value of the gap detection is in the range of ± 2 mm, this detection method has engineering practical significance.