Simulating the Printed Circuit Board Assembly Process for Image Generation

Abstract

The inspection of printed circuit board assemblies gradually incorporates deep-learning-based classifiers. However, such classifiers require a vast dataset. To our knowledge, such a dataset is not available. This paper proposes a method to simulate the assembly process aiming at generating such a dataset. The simulation of the solder joint shape forming during reflow and the creation of a photorealistic rendering of the assembled board have the most significant impact on the visual appearance of the results. Therefore, this paper focuses on the simulation of these steps. The calculation of the solder joint shape requires minimizing the surface tension energy. For this, the algorithm discretizes the energy equations over a heightmap. The proposed software architecture for the simulation is highly extendable and facilitate future development. Experiments with the simulation of solder joints of a chip resistor show a remarkable similarity to real images from an automatic optical inspection machine.