Legal ways of providing suction?

[dtgriscom]

A number of the example robots in the game animation seemed to be possessing the ball using suction. I just mocked up a rig with a small shop-vac and a 5-gallon bucket, and it grabs and holds a ball (with cover) very well. Now I'm wondering: how can I legally provide that suction?

Rule R29 lists the allowed motors, and includes the following category: "Drive motors or fans that are part of a motor controller or COTS". In the glossary, COTS has very few limitations beyond "off-the-shelf", so could I buy and use a small 12VDC vacuum cleaner, driven by a Jaguar? (I'm dubious, because if this is covered by COTS then it seems like an enormous loophole for powered devices.)


Thanks,
Dan

[Zuelu562]

In the past, we made a custom duct around the turbine thing (I'm bad at explaining, I had very little to do with it's construction). It was powered with a legal motor (IIRC, it was a banebots).

[EricH]

Take your vacuum apart, remove the motor from the suction device, and replace it with a legal motor as close as possible to the suction motor.

You could also use a venturi device off the pneumatics system, but that's not going to work nearly as well.


Where you went astray was cutting off the rest of that line about COTS. The full line reads, "Drive motors or fans that are part of a motor controller or COTS computing device", which a vacuum is NOT.

[czeke]

You could also use an airbed inflator, in reverse, using a curved shield with a good rubber seal.

[donkehote]

You can always disassemble the cots vacuum and remove the factory motor, replacing it with a first legal motor. Then it should be 100% ok. Might be a lot of work though.

Eric Ninjad me, darn. serves me right for not clicking submit reply

[Tom Line]

Spend some time on repair sites looking at different shop vacs. Some 12 Volt (rechargeable) ones use 550 motors - we experimented with these in 2010 for holding the soccer balls.

[dtgriscom]

Originally Posted by EricH

Where you went astray was cutting off the rest of that line about COTS. The full line reads, "Drive motors or fans that are part of a motor controller or COTS computing device", which a vacuum is NOT.

Oh, my goodness, is that confusing. In the decrypted PDF, the table in rule 29 ends at the bottom of page 17 with "Motor Name" given as "Drive motors or fans that are part of a motor controller or COTS", and "Max Qty Allowed" given as "Unlimited".

Then, at the top of page 18, "Motor Name" is given as "computing device", and "Max Qty Allowed" is given as "". Nasty, nasty, nasty. (And good catch, EricH. Thanks.)

[EricH]

Originally Posted by dtgriscom

Oh, my goodness, is that confusing. In the decrypted PDF, the table in rule 29 ends at the bottom of page 17 with "Motor Name" given as "Drive motors or fans that are part of a motor controller or COTS", and "Max Qty Allowed" given as "Unlimited".

Then, at the top of page 18, "Motor Name" is given as "computing device", and "Max Qty Allowed" is given as "". Nasty, nasty, nasty. (And good catch, EricH. Thanks.)

I'm using the PDF off the Manual site--clicking "Save As PDF"--and it's a LOT cleaner. I recommend you give it a try.

[asid61]

Following this thread. Could be interesting.

[dtengineering]

Hmm... if only teams had a 3D printer they could make their own impeller design.

What's that? You've got a 3D printer you say?

http://www.thingiverse.com/thing:29623/#instructions

http://www.thingiverse.com/thing:7273

http://www.thingiverse.com/thing:13188

Might help get you started.

Jason

[dtgriscom]

Originally Posted by Tom Line

Spend some time on repair sites looking at different shop vacs. Some 12 Volt (rechargeable) ones use 550 motors - we experimented with these in 2010 for holding the soccer balls.

Excellent idea: thanks.

[loyal]

Reading this reminds me of a seine in StarWars Phantom Menace during the pod race and the little robot got sucked in the turbine.

[yash101]

I think it's time for some machining . You could build a compressor-based suction-cup. However, that would generate a lot of suction, so you should really have a manual release valve.

How it works:

So you have a reciprocating piston, with an intake (suction) and an outtake (the atmosphere)


^=Output v=Suction intake
---^---v---
| Piston |
|====== |
| | |
| |----------------Pushrod
| | |
| |||\ |
| ||| \ |
| ===\ |
/ \
Motor Crankshaft




Hopefully you guys liked my ASCII Art
I don't know if CD likes ASCII art

[dtgriscom]

Originally Posted by yash101

I think it's time for some machining . You could build a compressor-based suction-cup. However, that would generate a lot of suction, so you should really have a manual release valve.

Won't work for any extended amount of time, because air leaks past the ball covering. You'd need continuous suction to maintain your hold for more than a couple of seconds.

Originally Posted by yash101

I don't know if CD likes ASCII art

Try the [code] tag; it will render using monospace fonts, e.g.

XXXXXXXXllllllll
llllllllXXXXXXXX

[yash101]

Originally Posted by dtgriscom

Won't work for any extended amount of time, because air leaks past the ball covering. You'd need continuous suction to maintain your hold for more than a couple of seconds.



Try the [code] tag; it will render using monospace fonts, e.g.

XXXXXXXXllllllll
llllllllXXXXXXXX

I'll try the code tag.

Also, the idea of the compressor is that it will continuously run when you want the ball to be held!