Home made encoder questions

Is there any chance I can get a higher res photo of this so I can compare the rings of the slits?

Thanks in advance. This really helps me understand my issues.

Scot

It can give you Phase Z
I cannot say it clearly.slight change in the second optocoupler will give you phase Z.halscope can use to tune it.
I am currently using alien english.I have the idea but cannot translate it english.you may not understand it.so
Moderators will helo you in this case.

its a grayscale disk so just google for image
but you may want something that fits your spindle / RPM / BOB / electronics

Correction there.i'm mentioned phase z there not phase b.sorry

I think this is all being over-complicated.

Just use plain slots in the disc. Then make one of them longer, for the index detector.
Then all you need is three fork-type detectors, possibly one a little deeper than the others for the index.

Arrange the A and B so that when A is exactly in the middle of a slot B is exactly on an edge. (not, as I once did, with B exactly between slots. 180 degree quadrature does not work at all)

And it is probably easier to get the disc laser cut. If you want a very fine slor spacing then the chaps who make solder stencils for PCB manufacturing can do very fine work:
photos.app.goo.gl/9eGSUs1yxW9AWuWF7
Those are about 50mm bore.

"Just use plain slots in the disc. Then make one of them longer, for the index detector."

That seems pretty simple. Evenly spaced slots with one longer toward the center is what I'm imagining. Is that what you meant?

"Then all you need is three fork-type detectors, possibly one a little deeper than the others for the index."

These are off the shelf parts? If the parts are available, I'm sure I can secure everything and wire it in.

Arrange the A and B so that when A is exactly in the middle of a slot B is exactly on an edge.

Now this is where I'm confused. When you're saying arrange A and B, are you talking about placing the detectors? I've never worked with these parts, so I'm unsure of exactly what you mean. Do they have aligning marks on them?

Thanks though. It's very helpful and it's painting a much more clear picture in my head.

As for the pictures you shared. Those are some you've made? They don't seem to match the description I'm imagining, though.

www.google.com/url?sa=t&source=web&rct=j...U3xI9necXd6-Ckt9w7TH

heliosoph.mit-links.info/make-your-own-q...ture-rotary-encoder/

This will give you some idea

Scot wrote: That seems pretty simple. Evenly spaced slots with one longer toward the center is what I'm imagining. Is that what you meant?

Yes.

These are off the shelf parts? If the parts are available, I'm sure I can secure everything and wire it in.

www.mouser.co.uk/Optoelectronics/Optical-Switches/_/N-abusc

Now this is where I'm confused. When you're saying arrange A and B, are you talking about placing the detectors?

Yes. If you buy ones with slotted screw mounting holes then you can adjust the phase using halscope to monitor it.

As for the pictures you shared. Those are some you've made? They don't seem to match the description I'm imagining, though.

Those were for a miniature reflective sensor ( uk.rs-online.com/web/p/photodetector-amplifiers/1783221/ ) , and were not a great success. I would not suggest using reflective sensors for that reason.

You can make a simple quadrature encoder with 3 detectors A and B offset half the distance between the slots and the index offset inwards to pickup a single longer slot. I have made similar using optical end stops for detectors.



I used drilled holes but slots are more forgiving.

MarkD