Vacuum

[Peter Matteson]

Originally Posted by jgannon

I'd venture that not only is that not clear, it's most likely wrong.

<R60> prohibits the use of electric solenoids, meaning electromagnetically controlled linear actuators. It notes that pneumatic solenoid valves, such as the ones found in the KoP, are legal. It makes no mention as to restrictions of their application... as such, you can use them in your pneumatics, you can use them as part of your end effector, you can use them as ballast, you can use them as non-functional decorations, and if you can make it work, you can most certainly use them to control a vacuum.

I will again point out that the rule quite clearly states that vacuum is not considered pnuematics. Therefore you would be using the solenoid for a purpose other than pnuematic. I think this is quite clear.

Also you want to use vacuum solenoids not pnuematic.

[roboengr]

The next thing on the valves is the pilot control of a valve. valves require a air pressure to work. Just keep that in mind. Dont use a venturi! It is not enough use a bima cylinder on a fisher price motor. the rest you will have to figure out.

Has anyone tried to use a vacume on the nylon cover? Tell the success or failure, please. I am not sure how much leakage there must be to over come in volume.

[jgannon]

Originally Posted by Peter Matteson

Therefore you would be using the solenoid for a purpose other than pnuematic. I think this is quite clear.

Peter, <R60> only talks about what parts are allowed to be on the robot. It says nothing about how they are allowed to be used. Whether the solenoids we are allowed to use will physically work for this application is up for debate, but please don't spread misinformation when the rules say something else.

[Peter Matteson]

Originally Posted by jgannon

Peter, <R60> only talks about what parts are allowed to be on the robot. It says nothing about how they are allowed to be used. Whether the solenoids we are allowed to use will physically work for this application is up for debate, but please don't spread misinformation when the rules say something else.

I am not spreading mis-information. We clearly disagree on the interpretation of the way this is written and both feel strongly that the way it is written agrees with our case. As such anyone who wants do this should directly ask about it through the FIRST Q&A system.

[Alan Anderson]

Originally Posted by Peter Matteson

I am not spreading mis-information.

As it turns out, you are.

The rule you are quoting, <R60>, is forbidding electric solenoid actuators. It's not saying anything about legal or illegal ways to use pneumatic solenoid valves. Ironically, the parenthetical comment that is intended to clarify the meaning is apparently what's leading you to misinterpret it.

Do you know what electric solenoid actuators are? They're the sort of thing that you find in chime doorbells, where an electric current causes a magnetic field to move a metal rod.

[martin417]

Originally Posted by Ziaholic

No comment on the legality of it ... but technically it'd be a challenge to convince me that it's worth the effort. We tossed that idea around for a little while during our brainstorming sessions, but it died off somewhat quickly.

For ball handling, with it's somewhat porous cover, the volume of air that you'd have to move would be huuuuge ... and the area of the suction cup would have to be pretty large. I don't think that a tank behind a solenoid would do the trick. I'd wager that you'd have to be constantly sucking large volumes of air to maintain a partial vacuum at the cup

Worth the effort? Challenge?

OK, some basic physics here. The ball is 40 inches in diameter. it is a sphere. So, you contact that sphere with a large circular hole (a box with a hole maybe?) behind which you have a vacuum source. Yes there will be leakage, so a centrifugal fan is in order (maybe a vacuum cleaner with the AC motor replaced with KOP motors?) If your circle is, say around 20" in diameter, that will give you an area of more than 300 square inches. With a delta P of 1 PSI, (Delta P is the difference in pressure, so 1 PSI of vacuum) that will give you 300 LB.s of holding force. Even a modest shop vac can create almost 2 PSI of vacuum, and a huge flow rate (relatively speaking) so any leakage around the rim is not even noticeable.

Not only is it doable, and worth the effort, look for it at a regional near you!!!

[dtengineering]

While this is slightly different from storing a vaccuum in a tank before a match, it certainly ends any debate on whether a vacuum gripper will work.

http://www.chiefdelphi.com/forums/sh...ad.php?t=63732

Jason