Sealed encoder group buy?

[peirvine]

Team 2175 would like 4 of the 3ft long encoder cables if they are available.

[ToddF]

Originally Posted by AdamHeard

why not go with the 360?

We are looking at using them for high speed velocity control (encoder attached to shooter wheel, for example). For a given sampling period, a 120 cpr encoder can be used for speed control on a wheel spinning 3X as fast as one on a 360 cpr encoder.

For controlling our drivetrain, the 120 cpr encoder gives .105" resolution on a 4" wheel directly coupled to the axle. If we need better than that, we'll attach to an intermediate gearbox shaft or use a mechanical multiplier.

[sanddrag]

I'm in for four.

[Gdeaver]

There are many options for encoders once you decide to spend some money. Is the US Digital The best buy. What CPR would most teams want to use. I'll Throw this out for thought. CUI makes the AMT102 and AMT103 encoders. Digikey link hear.
http://www.digikey.com/PTM/PTMPartLi...ng=en&ptm=5586
Now they are meant to mount on a shaft like the current US Digital that Andy Mark sells. The big difference is that they can be set to many different CPR up to 1024. You can turn these into a sealed unit with shaft. We made a base plate out of polycarb in the shape of the AMT102 base. In the polycarb base we mounted 2 precision ball bearings for a 1/4" stainless shaft. The programmers played with them last fall and they seamed to work well. We have not used them on a robot or really given them a test. Other teams have posted that they worked well. Could a run of base plates be done to add shaft capability to them? Then all that is needed is some shaft and bearing. I believe the bearing were about 5$ apiece. Is this an option?

[ToddF]

All,
I'll call US Digital again today and see if I can get a fuller explanation of the cryptic statement on the webpage.

In the meantime, updated order commitments:
2363: 8
696: 4
192: 8
4063: 4
1836: 8
1912: 8

Total: 40

[peirvine]

Hi, I am Peter from the Fighting Calculators, team 2175, and we would like 4 of them. Thank you for doing this!

[ToddF]

Just talked to the customer support rep at US Digital. She said the message comes up because the stock on the modules is limited at this time. She assured me that there are no plans for the S4 or E4P encoders to be discontinued. They are working to resolve the inventory issue, but plan to continue to supply them to FIRST teams.

I get the feeling that they might not be able to support an order of the magnitude necessary for the module to be incorporated into a consumer product with volumes of tens of thousands, but have no trouble supporting our small quantity orders.

[ToddF]

We are up to 44. Hopefully we'll reach 50 next week, and I'll be able to put in an order. I'm going to investigate the most cost effective method for shipping. I expect to purchase these with my own personal credit card. I'll be asking teams to send a check ASAP after the order is placed so I can pay the bill when it arrives. My statement date is the 28th of the month, so I'll shoot for placing the order around the end of the month to give as much time as possible to collect checks.

[ttldomination]

I'm curious about how you guys could go about interfacing this piece into a design?

Would you pop on a chain and use this as an idler, or perhaps just design to gear it in?

- Sunny G.

[Joey Milia]

Originally Posted by ttldomination

I'm curious about how you guys could go about interfacing this piece into a design?

Would you pop on a chain and use this as an idler, or perhaps just design to gear it in?

- Sunny G.

What 192 plans on doing is connecting the shaft of the encoder to one of the shafts in our gearbox using a flexible shaft coupling. The coupling doesn't have to be flexible but it'll just make our lives easier. I saw this set up on the gearboxes of a few teams this year, namely 1717 and 118. 118 had a very nice set up with a 3D printed mount for the encoder that spaced it making room for the coupler, we plan on doing something similar.

[T^2]

Originally Posted by ttldomination

I'm curious about how you guys could go about interfacing this piece into a design?

Would you pop on a chain and use this as an idler, or perhaps just design to gear it in?

- Sunny G.

This year, we used stock ballshifters, so we used the sub-optimal encoder setup with which those came.

Next year, I plan to incorporate the encoder mount into the first stage of our (custom) gearbox by extending the shaft out of the bearing, boring a slip-fit hole for the encoder shaft into it, cutting a 'x' pattern with a band saw, and then using a shaft collar to clamp the shaft in place. The top of the encoder will probably be held by a 3D-printed mount.

[404'd]

Originally Posted by ptan

Did anyone ever find out why US Digital discontinued the E4P? I got an email from them confirming that they don't recommend using the E4P for new designs, but suggested using the E5 instead (much more $$$).

Originally Posted by ToddF

Just talked to the customer support rep at US Digital. She said the message comes up because the stock on the modules is limited at this time. She assured me that there are no plans for the S4 or E4P encoders to be discontinued. They are working to resolve the inventory issue, but plan to continue to supply them to FIRST teams.

I get the feeling that they might not be able to support an order of the magnitude necessary for the module to be incorporated into a consumer product with volumes of tens of thousands, but have no trouble supporting our small quantity orders.

Sounds like they aren't discontinuing them but do have limited stock.

[ptan]

Found this interesting URL:
http://www.avagotech.com/pages/us_di...ross_reference

Hmmm... interesting that Avago was supplying the parts for US Digital, and now they are not.

[ToddF]

Status:
237: order shipped 6/29/13, check cashed
4063: order shipped 6/29/13, checked cashed
696: order shipped 6/26/13, check cashed
2175: order shipped 7/20/13, check cashed
1912: order shipped 7/20/13, check cashed
1251: check cashed, PM me a mailing address unless I should send you package to the school board address, which was the return address on the check.

Need payments from 192, 3081.

Todd F.

[MrRoboSteve]

3081 check went in the mail today.