A visual quality inspection system based on a hierarchical 3D pose estimation algorithm

Abstract

This paper presents a quality inspection system based on an efficient model and view based algorithm for locating objects in images and estimating their pose. Off-line, edge templates are generated from a 3D model. On-line, a hierarchical edge template matching technique generates matching solutions from which the pose of the object is derived. This approach tackles the difficult typical trade-off between tesselation size and efficiency. The proposed method works for arbitrarily shaped 3D objects. The accuracy of pose estimation exceeds that of state-of-the-art algorithms even if the objects are viewed on a cluttered background. Since no high-level feature extraction is required, the algorithm is robust against changing ambient conditions such as illumination. The inspection system is successfully tested on two real-world inspection scenarios in the engine production. © Springer-Verlag Berlin Heidelberg 2003.