strip feeder vision

[Toby Dickenson]

What vision pipeline is everyone using with ReferenceStripFeeder?

ReferenceStripFeeder default pipeline is using DetectFixedCirclesHough, but I think that is a bad choice.

* There have been long-standing reports of this not working right. It certainly doesnt work for me.

* The ReferenceStripFeeder wiki is anticipating problems. It has a "If your pipeline is not working" section, with a reference to a DetectCircularSymmetry alternative pipeline. This pipeline is what works for me.

* PushPullFeeder uses DetectCircularSymmetry pipeline for the same purpose.

* DetectCircularSymmetry was introduced in PR 1179 and a comment from Mark there says "The idea is to make these default pipelines someday use the DetectCircularSymmetry, if practice shows it works across many machine". I think this is now due.

Does anyone love DetectFixedCirclesHough or have another reason why we should not swap ReferenceStripFeeder to DetectCircularSymmetry?

Toby

[Dave McGuire]

On 5/20/25 10:03, Toby Dickenson wrote:
> What vision pipeline is everyone using with ReferenceStripFeeder?
>
> ReferenceStripFeeder default pipeline is using DetectFixedCirclesHough,
> but I think that is a bad choice.
>
> * There have been long-standing reports

> <https://groups.google.com/g/openpnp/c/TRK5Q4vZUbc> of this not working

> right. It certainly doesnt work for me.
> * The ReferenceStripFeeder wiki

> <https://github.com/openpnp/openpnp/wiki/ReferenceStripFeeder#cvpipeline> is anticipating problems. It has a "If your pipeline is not working" section, with a reference to a DetectCircularSymmetry alternative pipeline. This pipeline is what works for me.

> * PushPullFeeder uses DetectCircularSymmetry pipeline for the same purpose.
> * DetectCircularSymmetry was introduced in PR 1179

> <https://github.com/openpnp/openpnp/pull/1179> and a comment from Mark

> there says "The idea is to make these default pipelines someday use the

> |DetectCircularSymmetry|, if practice shows it works across many

> machine". I think this is now due.
>
> Does anyone love DetectFixedCirclesHough or have another reason why we
> should not swap ReferenceStripFeeder to DetectCircularSymmetry?

Honestly I gave up on vision altogether for ReferenceStripFeeder.
There just didn't seem to be any tangible benefit. I disable vision,
set the first and last holes manually, and it just works, and is a whole
lot faster.

I know that's not the answer you were looking for, but it may be
worth considering.

-Dave

--
Dave McGuire
McGuire Scientific Services, LLC
New Kensington, PA

[JW]

Dave, I actually never noticed that's even an option - good to know. 2 vision ops including settling time per pick on strip feeders adds up fast!

Toby, I have zero problems with this, but early on had a whole host of issues. It boiled down to the camera mm/pixel calibration being way off, sorted this and no problems since on the default pipeline.

[Toby Dickenson]

On Tue, 20 May 2025 at 15:22, JW <julian...@gmail.com> wrote:

Dave, I actually never noticed that's even an option - good to know. 2 vision ops including settling time per pick on strip feeders adds up fast!

Vision-free operation is a good choice of course, but it doesnt have to be *that* slow. Set the "extrapolation distance" feature to 40mm, and (after the first few holes) it only checks one hole in 10.

Toby

[JW]

OP, see the bottom of this page re camera scaling and strip feeder issues.

[JW]

I've just installed test build 2.3 and used the extrapolation distance, and see a 100% increase in CPH in an all strip-feeder build, so thank you very much!