Tube inner wall defect detection method based on rotary scanning micro laser distance sensor

Abstract

In this paper, an inspection device to detect the inner wall defects of oil tubes is proposed, mainly consisting of a micro laser distance sensor and a stepper motor. When the inspection device moves along the axial direction inside the tube, the stepper motor drives the micro laser distance sensor to rotate and scan the inner wall of the tube so that the coordinate data of the 3D point cloud can be obtained. In order to obtain the pose transformation matrix for the laser distance sensor coordinate system with respect to the device flange coordinate system, a particle swarm optimization algorithm is introduced. Finally, experiments are carried out on two real oil tubes and point cloud data are obtained which provide 3D information about the inner walls of the tubes. The measuring error of tube eccentric wear is within 0.2 mm, which verifies the effectiveness of this novel method.