Design of a high precision testbed of an automatic inspection system for detecting fine defects in PCBs

This paper shows the design of a high precision automatic inspection system for Printed Circuit Boards (PCB) using a 2D laser sensor. The main purpose of this setup is to detect errors in pasting and surface mount devices placement on the electronic boards. An ultra-stable table is used for supporting all the moving components and to absorb vibrations from the laser sensor. Motion control system is based on open architecture philosophy and developed using a PIC microcontroller. Final integration of all modules is done in a personal computer with a java code that commands the motion control module and receives data from the laser sensor; then processes and plots final results from the PCB inspection.