Research on Visual Measurement of Aperture and Hole Group Center Distance Based on Geometric Constraint

Hole is the most common symmetrical geometric structure of mechanical parts, and aperture hole center distance are important measured dimensions in machining. However, existing visual measurement methods often require high equipment installation accuracy low accuracy. To solve problem projection deformation hole: Firstly, a local coordinate system created, plane parallel to end face hole. Secondly, cone established, alike bottom cone, optical camera vertex. The space equation represented by coordinates point Finally, cutting established near imaging camera, intersection line between obtained, diameter circle obtained through parameters equation. In order errors edge points hole, constraints based on used improve This experiment takes automobile insert mold as part uses model this paper measure mold. results show that 0.018 mm, 0.05 maximum relative error 2.2%.