A pointer meter reading recognition method based on improved ORB algorithm for substation inspection robot
Zhe Liu, Hua Huang, Na Wang, Yingshuang Cao, Liang Zeng, Jianhua Zhang, Chentao Zhang
Abstract
Abstract Currently, pointer meters in substations are read manually, which causes a waste of human resources. To realize automatic reading of such meters, an accurate method for recognizing and reading of pointer meters was proposed for the inspection robot in substation. The new method consists of three steps. Step 1: the image is preprocessed with grayscale, noise reduction and piecewise linear grayscale transformation. Step 2: the Gaussian scale space is used to enhance the scale invariace of the ORB algorithm. Meanwhile, the RANSAC algorithm is used to screen the matching point pairs, which improves the accuracy of the feature pointer matching. Step 3: the Hough transform algorithm is utilized to fit the pointer. Finally, the reading result is obtained according to the angle method and the prior information of the pointer meter. The proposed approach can recognize and read the meter accurately. It has high reliability and engineering application value.