Fast retrievals of test-pad coordinates from photo images of printed circuit boards

This paper presents a data analytics approach for recovering test-pad information from images of printed circuit boards. The main aim is to obtain highly accurate information as input to a robotic flying probe tester. Such a tester is a mechatronic system that is able to perform a great variety of diagnostic testing on printed circuit boards without any additional circuit board documentation. In this work, a two-stage clustering process was applied on a dataset with 71040 pixel records obtained from an electronic circuit board image. In total, the method discovered 128 locations on the circuit board that are potentially the test pads. Visual inspection found that all the 120 legitimate test pads on the circuit board were retrieved. The other eight locations were not really test pads and were removed (i.e., Recall = 100%, and Precision = 93.25%). We propose this image analytics approach as an effective way to speed up the recovery of test-pad locations from printed circuit boards.