Blind Conveyor Tracking ?

I have an application that will require me to see product on a conveyor (lets call this photoeye 1) , triggger a camera (camera 1) then reject (after photoeye 2).

Now I know there are 19 ways to skin this cat.

But it's a little bit of precarious situation in that there is no encoder on the conveyor, so I can't really 'track' it.

Also the spacing is completely varied since its just product on a flat top conveyor, so there is no pockets or definitive index sections.

My initial thoughts were to use PE1 to set a bit in a shift register, marking product present, i would have an additional register for marking the product as bad. They would each shift with the PE2 being made, if a you have a 1 present in the product present and the product bad register at the PE2 position, then reject.

I think the issue here would be that the register would have to prime so the system would start but you couldn't really start tracking until your register fills up, so the first 3 bottles or so would be question marks.

Just thinking outloud.

I can probably add additional eyes if necessary but encoder is out of the question.

If all else fails I'll just move the camera as close as possible to the reject station, eliminating the need to track.

I once put a prox at one of the sprockets on a conveyor and used it as a "poor man's encoder". Perhaps that may be an option for you to help track the product.

Otherwise, a FIFO would probably be the way to do it.There are plenty of examples here on the forum.

If multiple parts are allowed bewteen Photo-eyes then a shift register pulse is needed.

Also there is no need for part present only bad part. Your decision will be based on 0 or 1. 1=reject on or 0=reject off

Your best bet is reject after camera before your camera makes the next decision.

Ditto- Highly Effective

JordanCClark said:

I once put a prox at one of the sprockets on a conveyor and used it as a "poor man's encoder". Perhaps that may be an option for you to help track the product.

Otherwise, a FIFO would probably be the way to do it.There are plenty of examples here on the forum.

Click to expand...

Product data is entered into "virtual" data cell [0] in the top of the ARRAY, and execute a FIFO for every sprocket pulse. You can expertly monitor the product data as it moves down your conveyor line.

Even though Jordan named it "poor mans" encoder... It is actually the most economically responsible, and competitive solution for you, and your customer.

So let's now call it the "smart mans" encoder. Thanks Jordan