Image Registration for Multimodal Inspection of Mechanical Parts

Image registration is the process of aligning the corresponding features of images in the same coordinate system. Multimodal registration has been widely used in medical imaging and geographic imaging. However, it has not been broadly applied in the inspection imaging of mechanical parts. Multimodal registration can improve inspection accuracy and quality by combining complementary inspection data from different inspection methods, or “modalities”. The research focus of this work is to develop a computational algorithm to register a CMM point cloud with a CT image in the 2-D (planar) domain. Dealing with outliers is the major concern for achieving required registration accuracy. Targeting solving this problem, a new registration metric is proposed in this work, which makes application of the traditional ICP (Iterative Closest Point) algorithm robust, by optimizing the search for closest points.