The invention provides a
pipe thread positioning and measuring method and
system based on three-dimensional vision, and belongs to the technical field of industrial
automation and three-dimensional vision. According to the method, a measuring
system composed of a
robot measuring
system and a three-dimensional visual locating system is built, and hand-eye calibration is completed; the method comprises the following steps: acquiring a three-dimensional
point cloud model of the end part of a
pipe thread workpiece, and extracting an end surface normal vector, a tangent vector and a circle center coordinate through preprocessing, cylinder fitting, near-end
surface point cloud extraction and end surface
circle fitting so as to establish a measurement reference coordinate system; and converting the reference coordinate system to a
robot base coordinate system based on a hand-eye
calibration result and the
tail end
pose of the
robot, generating a robot moving trajectory, guiding the robot to be positioned to a measurement position, and completing preparation before measurement. According to the invention, automatic high-precision extraction of the
pipe thread measurement reference is realized, the problems of non-uniform reference, large error and low efficiency in traditional measurement are solved, the method is suitable for various pipe thread workpieces, and a reliable basis is provided for subsequent high-precision measurement.