Re: Balls getting stuck in hopper
 

We can't really give a difinitive answer unless we know what kind of hopper is being used.

Our team is using a hopper that is just meant to hold a mass of balls, and we did have an issue of them getting stuck in there. If you keep the balls moving around some, then they aren't going to be stuck. If you are going for a different stratergy and a different hopper, look at some of the other posts to see if they apply.

Re: Balls getting stuck in hopper
 

hehe, i could give you the first idea our team had...you could shake and shake like central did a few years ago..lol, i love watching that

Re: Balls getting stuck in hopper
 

central? watching wat?

Re: Balls getting stuck in hopper
 

My suggestion is a pneumatic piston that just pokes at the balls when needed for un-stuckage. however, if you don't already have a pneumatics system on your robot, then you might want another alternative

Re: Balls getting stuck in hopper
 

We're trying a conveyor belt on one side of the hopper that travels UPWARDS. This is supposed to lift balls up out of a jam.

Re: Balls getting stuck in hopper
 

What kind of net are teams using: volleyball, badmitton, fishing?
We bought a fishing net to try. I am worried about balls sticking some.



Carolyn

Re: Balls getting stuck in hopper
 

I very much doubt that balls would end up getting stuck when you use a fishing net. The holes should be small enough so that fish would not escape through the holes, and I am pretty sure that the balls we are using are much bigger than the fish.

I have not seen a badmitten net in my life ever so I can't help there, but the nets used in volleyball should be big enough as well.

I am guessing that your team designed a funnel for your robot. the use of a net is actually a dead give away. how about letting us in on how your team designed it.

Re: Balls getting stuck in hopper
 

An agitator would be easy and cheap, but you could build differant gravity feed hopper.

Re: Balls getting stuck in hopper
 

Really it depends but I would think to pull the mechanism used for pulling the balls in to the shooter more.

Re: Balls getting stuck in hopper
 

Simple fix. Go back to week 1, and decide not to use a hopper. ;)

Re: Balls getting stuck in hopper
 

If your using a rotating wheel shooter try adding weight on the rim of the wheels. This should make the wheel unbalanced and shake similar to cell phone vibrators. The shaking shouldn't disrupt your shooter , but try it and see.

Re: Balls getting stuck in hopper
 

================================================== ======
Well, we had a rim with the wide end of the net and if came to a narrow end with a rim. However, balls still got stuck. We looked at putting in a funnel towards the bottom, but still had 2 or 3 ball combinations that stuck. We had the fishing net taunt and they still stuck. We tried a turning thing that would sometimes unstick them but even that was unreliable.

So as the person said above we went back to some beginning ideas and are mocking up now. Maybe hopper plus tracking.

Hope this helps. I am still interested how teams with the netting are working and not sticking. :confused:

Carolyn

Re: Balls getting stuck in hopper
 

I am not sure what you mean, but I am guessing that when you say "narrow end" you mean a slim tube big enough for one ball to fit through. This will give the balls less room to pass and create friction. As a ball spins downward due to slope it rubs of against the ones behind it. If the balls don't end up shredding before coming out they most likely won't come out at all. How I know all this if this is my first year in FIRST? One of the professors from the California State University in Northridge had warned us against this.

as for the hoppe+tracking: well, that would be one annoying challenge. Could be used for autonimous mode, programming this to happen when the servos connected to the cam reack this position and react accordingly.

I still wonder how balls actually manage to get stuck on fishing net.

Re: Balls getting stuck in hopper
 

When the previous posters said "tracking" I believe they meant a mechanical track that the balls would roll on. Like the track for grain in a barn, not tracking as with the camera.

Also, I dont think that a ball rolling down something like a PVC pipe (or similar) will be be shredded. It will come out without shredding, as all of our tests have shown. As long as there are no overly sharp edges (such as jagged aluminum), there is no reason why a ball with little pressure on it will shred.

Re: Balls getting stuck in hopper
 

^ lover and worshipper of the three- eyed demon who calls himself Hiei

Quote:

Originally Posted by chinckley ================================================== ====== Well, we had a rim with the wide end of the net and if came to a narrow end with a rim. However, balls still got stuck. We looked at putting in a funnel towards the bottom, but still had 2 or 3 ball combinations that stuck. We had the fishing net taunt and they still stuck. We tried a turning thing that would sometimes unstick them but even that was unreliable. So as the person said above we went back to some beginning ideas and are mocking up now. Maybe hopper plus tracking. Hope this helps. I am still interested how teams with the netting are working and not sticking. :confused: Carolyn

A fishing net? Quite intuitive; it's difficult to imagine balls getting stuck in that. However, to rectify your dilemma, you could use dual pneumatic pistons on the smaller rim that constantly move it around one or two inches along the vertical axes. This would jar any caught balls; you would, however, have to add an accordion-like piece below the funnel.

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