Relative pose is an important monitoring item in the assembly process. Aiming at the relative pose measurement requirements during the docking of large-scale components

a vision-based real-time measurement method of relative pose is proposed. Based on the monocular vision technology

relative poses of sections is calculated in real time with the images of cooperative targets

which can be useful for the assembly work. Firstly

a real-time relative pose measurement system is designed

including a vision measurement unit equipped with a monocular camera

and a cooperative target for pose calculation. Secondly

the complete process of relative pose measurement is studied

including system calibration method and real-time pose calculation method. Finally

the accuracy of the pose measurement system is tested in laboratory. The result shows that the repeatability of the pose measurement system perpendicular to the optical axis can reach 0.02mm

the repeatability along the optical axis is better than 0.2mm

and the time of pose measurement is less than 0.3s. The network measurement of multi-measuring unit is simulated

and the repeatability perpendicular to the optical axis is better than 0.1mm

the repeatability along the optical axis is better than 0.2mm

and the time of pose measurenent is less than 1.3s

which satisfies the requirement of pose monitor and docking state estimation for large-scale component docking.