To ensure that the crane can smoothly calibrate and align the lifting
rod with the beam body lifting hole, it is necessary to use image
processing technology to locate and detect the corner coordinates of the
crane’s lifting rod. Traditional corner detection methods are not
suitable for this scene. This article proposes a new idea for corner
positioning, which locates corner coordinates through the intersection
of straight lines. Firstly, using the R and G channels of the RGB color
space to construct a grayscale difference map is beneficial for Otsu’s
threshold segmentation; Secondly, this article proposes an optimal
adaptive threshold determination method to filter the number of votes in
the clustering results, eliminate interfering straight lines, and
improve the clustering centroid calculation method based on the weight
calculation formula of different voting proportion, replacing the
original clustering centroid as the basis for line fitting; Finally,
calculate the corner coordinates of the crane’s grab boom based on the
straight line fitting results, and compare the recognition accuracy
under different lighting conditions. This method is significantly
superior to traditional corner detection methods, providing a method
basis for solving the algorithm accuracy and robustness problems of port
cranes under multiple environmental variables.