A new approach to 3-D object inspection using 2-D camera views is proposed. With input objects put on a turntable for inspection, a top view of the object is first taken by a top camera right above the table. The object shape boundary points are extracted, and the centroid as well as the principal axis of the shape are computed for top-view registration with the model shape, using the generalized Hough transform. The distance-weighted correlation is then used as the similarity measure for shape matching. Input objects with low similarity values are rejected. Non-rejected objects are inspected further from lateral views, using a lateral camera for image taking and the turntable for object rotation. Experimental results with a high inspection rate and a fast inspection speed show the feasibility of the proposed approach.
