Monocular zoom vision-based coaxiality measurement method for butt joint of large-scale cylinder frame

A large-scale cylinder frame butt joint coaxiality measuring method based on monocular zoom vision is characterized by comprising the following steps: 1) a zoom camera is adjusted to a near-focus end, an image is collected, characteristics of a front end face inner circle and a rear end face inner circle of a frame body and characteristics of a front end face inner circle of a cylinder body are identified, and space poses of the front end face inner circle and the rear end face inner circle of the frame body and the space poses of the front end face inner circle of the cylinder body are solved; 2) adjusting the zoom camera to a far-focus end, collecting an image, identifying the inner circle characteristics of the rear end surface of the cylinder, and resolving the inner circle space pose of the rear end surface of the cylinder; 3) fitting the axis of the transition frame; 4) calculating the coaxiality of the front end face and the rear end face of the cylinder; and 5) judging whether the butt joint precision