Graph-based surface merging in CAD-guided dimensional inspection of automotive parts

A CAD-guided camera planning system for dimensional inspection of automotive parts has been developed. This system utilizes the CAD information of inspected parts and the camera model to plan camera viewpoints that satisfy certain task constraints. To overcome some limitation inherited in the existing method, a new CAD data representation is adopted to combine the advantages of parametric surface and triangulation. A graph-based surface merging algorithm is proposed to reduce the number of flat patches, and eventually, the number of viewpoints. Tests on different real part models show that the surface merging algorithm is effective. This algorithm can also benefit many other CAD-guided robot path planning applications.