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Fiducial - Pattern Matching vs Center search based on fiducial shape

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#84751

Fiducial - Pattern Matching vs Center search based on fiducial shape | 8 April, 2020

Hello Fellas, I m looking for some information about Fiducial methodology used in SMT machines. My Machine has two options for fiducial- Pattern Matching vs Center search based on fiducial shape. but I don't understand difference. In both methods we have to select the fiducial shape and system will be finding the center. So whats the difference???

Thanks for ur time.

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#84752

Fiducial - Pattern Matching vs Center search based on fiducial shape | 8 April, 2020

I'd have thought that centre search uses an algorithm to find the dead centre of a specified geometric shape. Pattern recognition basically has a picture of the area of the board selected and tries to match it with what the camera sees. ( so it doesn't have to be geometric or symmetrical ). We always use standard fiducial correction with a circle ( either a circular fiducial or a plated 'through hole' )

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#84755

Fiducial - Pattern Matching vs Center search based on fiducial shape | 9 April, 2020

I don't think that there is an industry standard on that. Each machine manufacturer will have to say what they mean.

I think the first option looks at what you taught and then looks at what it sees when looking for the fiducial. The other method sounds like it is using a vector based approach and is looking for something that matches the parameters that you have told it. Do you have to "teach the fiducial" with one method but only test it with the other? Similar to different approaches for AOI.

But in any case I think the only people that can tell you are the people that made the machine. Sometimes I swear major OEMs got together to make sure they didn't overlap terms with each other.

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