Line-Structured Light Image Processing Procedure for Pavement Rut Detection

Abstract:

Pavement images with the laser line-structured light pattern can be used to detect the pavement rut. The work principle of the laser line-structured light in rut detection is introduced in this study and a line-structured light image processing method is proposed to deal with the complicated characteristics of the pavement surface textures as well as the technical conditions. The image processing procedure can be divided into two parts, the extraction of the pavement cross-section curve and the output of the rutting parameters. The pavement transverse section curve can be obtained through three steps. First, light center extraction, which aims to find the true center of the line-structured light through Gaussian fitting. Second, light center connection, which restores the characteristics of the entire pavement transverse section by linear interpolation. Third, smoothing of the light center curve, which can reduce the impact of pavement surface texture and other interferences. The output of the rutting parameters is based on the envelope line of the pavement transverse section curve. The maximum rut depth and the rut area can be calculated as the rutting parameters, and the pavement transverse section curve can also be used to describe the characteristics of the pavement transverse deformation. The rut sample is used to test the rut measurement method and the image processing procedure above. The result shows that the line-structured light can measure the rut depth accurately and the processing procedure proposed in this work has the potential to be applicated in practice.

Key words:pavement deformation; pavement detection; rut detection; image processing; line-structured light