Are COTS shop vacs legal? They have motors

[Nuttyman54]

No, a COTS shop vac as is is not legal if you are using the motor it comes with. However, it is legal to replace the motor in it with one from the kit of parts (the Fisher Price and Mabuchis are good choices).

Many teams are using the impellers and other mechanical components out of shop vacs, coupled with motors from the kit to power their vacuum mechanisms

[RoboMaster]

Originally Posted by Nuttyman54

No, a COTS shop vac as is is not legal if you are using the motor it comes with.

Yep, apparently. See my edit.

[Dave Flowerday]

You didn't finish reading R72:

For the purposes of the FIRST competition, a device that creates a vacuum is not considered to be a pneumatic device and are not subject to the pneumatic rules (although they must still satisfy all other appropriate rules). These include, but are not limited to, venturi-type vacuum generators and off-the-shelf vacuum devices (as long as they are powered by provided or permitted motors).

Therefore, R72 does not apply to your shop-vac.

{edit} I think you're misinterpreting the word "provided". Provided means "in the KOP", not "provided in the COTS vacuum".

[EricH]

What part of <R53> is hard for you to understand? If it isn't permitted, it's prohibited. <R52> lists the only permitted motors.

If you have a motor that is not listed in <R52>, then you have to replace it with one that is listed in <R52>.

By using the stock motor with the vacuum, you violate <R53> and, by extension, <R30-B>.

Your team member needs to re-read <R52> and <R53>.

[45Auto]

Did you read the last line in parentheses of R72, the rule you quoted??

(as long as they are powered by provided or permitted motors).

The only provided or permitted motors are the ones that FIRST gave you in the Kit Of Parts (or their exact replacement). The motor that comes on the shop vac is NOT permitted. As was stated earlier, you have to take the shop vac apart and replace the motor.

We replaced the motor from a cheap Wal mart 1 HP, 1 gallon shop vac with one of the KOP Fisher Price motors. Cut the shaft off the existing motor then ream it on a lathe to a press fit on the Fisher Price shaft - .125 inches. If you try to drill it with an 1/8 inch bit it will most likely be too big. It works perfectly, you can't knock the ball off it.

Bayou Regional Champions with 1461 and 3362 - See you in Atlanta!

[Madison]

Originally Posted by EricH

What part of <R53> is hard for you to understand? If it isn't permitted, it's prohibited. <R52> lists the only permitted motors.

If you have a motor that is not listed in <R52>, then you have to replace it with one that is listed in <R52>.

By using the stock motor with the vacuum, you violate <R53> and, by extension, <R30-B>.

Your team member needs to re-read <R52> and <R53>.

Settle down.

[robself705]

Our team actually took two shop vac impellers and mounted them on a custom turned steel shaft from the lathe. We then used the built in housing from the vacs to enclose the impellers. We then built a wooden frame to mount the impeller housing and bearings for the shaft. In the middle of the wooden frame, we put belt sprockets on the shaft and mounted two fisher price motors with belt sprockets as well. This gives us a VERRRRRYYYY powerful vacuum. Two fisher prices are more powerful by one cim by a factor of around 1.3. Check out this link at around 1:22 to see exactly what I mean: http://www.youtube.com/watch?v=X_dnzebFqDk

Good luck! Let me know if you have any questions!

[RoboMaster]

...pneumatic system items specifically permitted on 2010 FRC ROBOTS include the following items... ...off-the-shelf vacuum devices (as long as they are powered by provided or permitted motors).

We understood that there were certain permitted motors allowed, but thought that vacuums were exempt because the above rule allowed them. We also took the word "provided" to mean provided in the COTS vacuum, but a lot of people are saying this means provided in the Kit of Parts.

I have heard a bunch of times how teams needed to/have replaced vacuum motors with KoP motors. So this matches up with the "illegal" opinion.

I also look at the original third rule I posted, <R53>, which bans all electric motors except permitted ones. It includes the phrase "except those permitted in <R52> [basic permitted motors list]" and if the vacuum motors were to be allowed it would probably also reference that related rule too. More evidence for the vacuum motors being "illegal."

The FRC manual also says to not twist or legalize the rules and always take them in the spirit of Gracious Professionalism. When I rethink these rules in terms of GP, I actually think that this would mean the vacuum motors are "illegal". One could argue that the vacuum motor is part of the COTS component and also doesn't offer a large energetic/mechanical/power advantage, but theoretically it could. Motors are a source of power and there is a reason FIRST restricts them and all other such devices (compressor, pistons, etc): to give teams a fair advantage. While it is not technical, I think this is a big support for the "illegal" viewpoint.

I will check with my team and see what they think about what has been said. Personally, I could still take the word "provided" multiple ways, so I don't know. We might just post this on Q&A to completely be sure. Thanks for what has been commented so far!

[EricH]

You can also show them Rev C of the Inspection Checklist. The following can be found on the second page:

____ Only KoP Motors – 5 CIM, 2 Denso Left, 2 Denso Right, 2 Fisher Price, and 2 Mabuchi. <R52.A,D,E>

Come to think of it, it might help you to go over that checklist quickly in the pits before going to inspection. The less stuff the inspectors find that doesn't pass, the faster you get done.

[jamie_1930]

Just go to the Q&A, the opinion of anyone on chief is just opinion we have no official ruling.

[RoboMaster]

Originally Posted by jamie_1930

Just go to the Q&A, the opinion of anyone on chief is just opinion we have no official ruling.

Yes, but posting on Q&A is a hassle since you can only use one account. We just wanted to quick see what CD said.

[EricH]

Originally Posted by RoboMaster

Yes, but posting on Q&A is a hassle since you can only use one account. We just wanted to quick see what CD said.

One account, and I think they're only really answered once a week at this point in time. If you're going to develop this and you have a Week 4 event, you'd no sooner get a ruling than you'd have to pack up the vacuum.

Also remember: some of the folks on CD are inspectors of various stripes. Those are the folks who'd ultimately have to pass the robot or not pass it at the event. They can contact the GDC if they need to, but they'll usually use the checklist or the Manual first.

[jamie_1930]

Originally Posted by EricH

One account, and I think they're only really answered once a week at this point in time. If you're going to develop this and you have a Week 4 event, you'd no sooner get a ruling than you'd have to pack up the vacuum.

Also remember: some of the folks on CD are inspectors of various stripes. Those are the folks who'd ultimately have to pass the robot or not pass it at the event. They can contact the GDC if they need to, but they'll usually use the checklist or the Manual first.

In that case, this is the man to talk to
Al Skierkiewicz

[EricH]

Originally Posted by jamie_1930

In that case, this is the man to talk to
Al Skierkiewicz

I happen to be an inspector, though not a lead inspector. Yes, I did pass the certification test.

Al is one of the people I was thinking of when I wrote that post. Dave Brinza (LRI at Los Angeles) was another.

[Mark McLeod]

Here's a related Q&A:
http://forums.usfirst.org/showthread.php?t=13981

It addresses COTS clutches, but the GDC makes it clear that while the COTS part is legal, if it uses any non-Kit motors, those are not-legal.