WHY FIDUCIAL MARKER PLACEMENT IS CRUCIAL FOR AUTOMATED ASSEMBLY OF PCBS

Abstract: What are Fiducial Markers?

How Does Fiducial Marker placement affect component insertion?

How Are Fiducial Markers Set in Place on Printed Circuit Boards?

What happens if no fiducial markers are utilized?

Fiducial marker placement tips

Did you ever wonder how vision and robotic systems in surface mount assembly machines (SMTs) are able to situate electronic components exactly where they need to go on a tiny printed circuit board, within extremely close tolerances?

The targets for an SMT vision system are multiple: matching the circuit pattern of the artwork with the top or the bottom of the fabricated printed circuit board (PCB), determining the location of the PCB along the x, y, and z planes, and locating the precise position on the circuit to place a specific component. With the help of the indexing (positioning) system, the PCB is positioned per the program parameters, however, this positioning is not exacting enough for component placement. Fiducial markers provide reference points for imaging systems.

What are Fiducial Markers?

Although it sounds like a financial term, the term “fiducial” means a fixed basis of reference for comparison purposes. In general, a fiducial marker is an embedded object or a surface mark, used as a directional measure or reference point for indexing and imaging systems.