Algorithms fo computerized inspection of rectangular and square shapes

Vision systems are increasingly being considered and implemented as an alternative to manual inspection and manual gauging in manufacturing systems. Inspection for geometric shape and size is essential in automated quality monitoring. The techniques used to perform this inspection need to be practical to satisfy time and equipment constraints, and make the system cost-effective. This paper presents practical and useful techniques based on the Euclidean least-squares method to inspect production parts with rectangular and square shapes. The techniques determine the optimal parameters of the straight lines that define the four edges of the object being inspected.