In order to achieve 3D digital measurement of large-scale equipment

based on OpenMVG (Open Multiple View Geometry)

a technical framework

which is suitable for industrial photogrammetry

is generated. Firstly

the coded points in the set of images were identified and positioned

the matching relationships between multiple images were built by ID number

and the data interface for OpenMVG was established. Then

by means of OpenMVG solver

the 3D coordinates of the coded points at the normalized scale were solved. The actual scale factor was restored by using multiple scale bars arranged in the scene. Finally

the coordinates of the code points

the transformation matrix between the images and the camera parameters were obtained

which constitute the core parameters of the industrial photogrammetry framework and can meet many applications of industrial photogrammetry. Taking an airplane as a test object

which is in the space of 10m × 3m × 4m

the number of images by photogrammetry capturing is more than 500. The finally measured error with our method is less than 0.085mm. Compared with the current commercial photogrammetry system

the proposed method can achieve the same accuracy level with greater efficiency and expansibility.