Visual Inspection of Soldering Joints

Vision system for the inspection and quality control of soldering joints on circuit boards. Able to analyze conical joints regardless of their high reflection.

Projects: BMS, BMS II, BMS minimalist and BCB.

In this line of projects we developed machines that inspection the pin-joints in printed circuits. These weldings can be done either manually or by robots.

The main problem of welding inspections is that the welding itself is made out of tin, which behaves as a mirror reflecting its surroundings, and this creates a lot of ambiguities and confusion in the scene. Taking profit of these characteristics, we tackled this problem by using illumination domes that lighten the weldings with different colours in three different directions. This allows us to have a 3D representation, which makes easier to decide whether the piece is defective or not, but it constraints the hardware set up. Our contribution is a system that solves this problem by using a unique white light source.