Automating the sensor placement task for accurate dimensional inspection

Deriving accurate 3D object dimensions with a vision system for inspection tasks demands the use of multi-station sensor configurations. In such configurations, each feature appears in images from multiple viewpoints facilitating its measurement by means of optical triangulation. This paper reviews photogrammetric expertise in the design of such configurations, including the bundle method, a general math model for optical triangulation, and fundamental considerations and constraints influencing the placement of sensor stations. Finally, we report on development of an expert system for automating the design of multi-station configurations. Examples showing the current status of this work are given