Hello wonderful world of Chief Delphi!
My team came up with an interesting idea for picking up the PowerCubes in this years game, and were wondering if you had any insight. We had the idea of using a sort of vacuum to attach to the cubes to place them in the switch and scale. If you could shed some light on where to find information regarding the legality of this idea, that would be great!
Thank you in advance,
Ethan Potinsky
FRC 4003, TriSonics
Hello,
You may want to check out ARMABOT’s vacuum
https://www.armabot.com/collections/frontpage/products/armavac
If I remember correctly, Team 3656 used a vacuum for their robot in 2016 (Stronghold). It worked really well, maybe contacting them might be an option?
You ask where to find information on the legality of such a component. Fair warning, you walked right into this one…
In the FRC Game Manual, Section 8. Particularly 8.6 and 8.9. (One of those references is a “red herring”, meant to test your ability to read the Game Manual.)
You may also want to look at rule G19 in Section 7 of the same source.
We used a vacuum to pick up the totes a few years back and won the Creativity Award for our design. It was legal. We swapped out the motor of an air break with a CIM. We used to of these and cups made from a 3D printer. The problem this year is that the cover for the cube is porous so you can’t get a hold of it.
It does seem to be fabric enough that it probably would be trouble, but I’d take a shopvac to it to see if you get any suction. If you do, it might be viable.
The legality issue is just that you have to use an approved motor. So you have to replace the motor to whatever vacuum impeller you end up using.
We tore up some vacuums (little portable shopvacs seem to be the better choice) and took off the motor and replaced with a legal motor. For the cup we were using a large trashcan lid with rubber sewn/glued on. We’d have to go with smaller cups this year, I’m not sure what would be best.
The covers on the Trackballs in 2008 were fabric. At least one team used suction to pick those up.
Just because it’s fabric doesn’t mean a vacuum won’t work, it just makes it more difficult.
Back in 2010, we used a vacuum to handle soccer balls. We bought a component like this from a boating supplies store and swapped the motor with a legal FRC Fisher Price motor, and then used some air duct tubing to handle the exhaust.
2008 would be our team. Our problems there were that the ball would roll away and so we pushed it against the driver’s station helped seal it sometimes, and we had to turn around for our catapult. Still, Flingo is one of our coolest robots.
I think 190 did a vacuum too that year, but it seems to have been a giant failure of playing the game.
I think the ball inside the fabric made it possible, where the milk crates are porous. But like I said I haven’t tried a shopvac, so I can’t be sure.
If you want to look at vacuums from 2008, look no farther than 1771. 190 had one that worked just fine, but 1771’s was like 4-6x more powerful than ours and was REALLY FREAKING COOL, plus it made a great sound when they shot. They won the Championship Creativity Award for it.
190’s vacuum was a shopvac impeller installed on a Fisher Price motor. The shopvac originally had a 500 series motor, so it was an easy swap. You could probably do the same, though converting to a 775 series may take more work. The Armabot COTS option seems nice.
The big thing that made all of the 2008 suction cups work was surface area. The vacuum generates a pressure differential, but the larger area you can spread it out over, the more total force you can get. 190 ended up with a 13" diameter suction cup by the end of the season, and 1771’s was even bigger.
TLDR, you can pull suction on a porous surface, if you can generate enough pressure difference and spread it over enough area.
Totally, it could work, but well is the real question for these pieces.
I don’t remember much about 190 then, but it came up earlier that while the vacuum probably worked well, the way it played the game wasn’t good by their standards. Looking at TBA they were 12-15-1 in official play (where in 2007 they were 22-13-1 and 22-12 in 2009).
We did try this with a vacuum pump in our shop, with the power level lowered to roughly the equivalent of a CIM. We used an empty cream cheese container and about 1 PSI was enough to firmly grasp the cube. It was more difficult to remove than I thought! I’ll see if someone took a photo…
Designing a vacuum can suck.
Shop Vac motors are several times more powerful than the ones allowed.
Dyson vacuums can operate in excess of 100,000rpm, well beyond the reach of the kit or allowed motors, too…
So your challenge is to design a system to run off of a less-capable motor, which also happens to be attempting to hold a less than ideal surface.
Good luck, I would love to see what teams come up with!
+1.
Shop-Vac currently manufactures a 12-volt vacuum cleaner. Not sure it’s worth it over a normal one though if the motor will be swapped anyway.
If you do decide to attempt this, make sure that the impeller/fan can handle the RPM of the motor you intend to drive it with, and also that the suction cup can handle the pressure. Most vacuum hoses and components should be fine, as this happens often during their normal use.
Somewhat related: vacuum cleaners are sometimes used to lift bowling balls as a demonstration of suction power. This is only possible because the suction cups become vacuum sealed to the bowling balls, so any vacuum is able to do this. The only demonstration of power here is how long it takes to remove all of the air and create the seal.
The bottom of the crates are grids just like the sides
I don’t have any photos or videos to show, but we tested a AM redline powered vaccum tonight on the cube and it was very effective. It held onto the cube a lot better than I expected.
Couldn’t it also blow?:rolleyes:
2491 did this, and it worked fairly well for picking up and holding onto the cubes. This won’t be our final design, but it’s interesting nonetheless.
Does anyone know the cfm or how much suction the Armavac has?