Drum shooter?

[viggy96]

Does anyone here think it would be reasonable to shoot balls using a spinning drum, rather than a wheel, so that you could shoot 2 or 3 wide?

Our current plan is more or less inspired by 148's 2009 bot, Tornado, (though without the fancy ball storage) (https://www.youtube.com/watch?v=aCVLZFyEI1Y) and we were trying to see if we could put a shooter on it as well, to shoot for the high goal. Being able to empty the hopper faster would be very beneficial.

[SenorZ]

Nothing wrong with a drum to process balls. But they're much smaller than the 2009 balls. So there is a risk or jamming, or having a very narrow helix.

Trick is getting them to a high speed shooter.

[viggy96]

Originally Posted by SenorZ

Nothing wrong with a drum to process balls. But they're much smaller than the 2009 balls. So there is a risk or jamming, or having a very narrow helix.

Trick is getting them to a high speed shooter.

I guess my original question wasn't clear. I was thinking about using a drum as the high speed shooter, in order to be able to shoot multiple balls at once, rather than a single wheel, which can only shoot one ball at a time.

[Boltman]

Drum could work .

[SenorZ]

I'd love to see a continuous stream of balls flying out of a drum!

Consider the power consumption. The balls are pretty light, but trying to pull several up from the bottom of your hopper with enough speed to propel them 5+ feet in the air, all using the same mechanism is going to be challenging.

[rich2202]

Originally Posted by viggy96

Does anyone here think it would be reasonable to shoot balls using a spinning drum, rather than a wheel, so that you could shoot 2 or 3 wide?

The Fuel is 5" wide. The opening 17.5-21.5" wide depending upon how you look at it.

IMHO, you will be challenged to get a 2 wide stream into the opening.

[Boltman]

Originally Posted by rich2202

The Fuel is 5" wide. The opening 17.5-21.5" wide depending upon how you look at it.

IMHO, you will be challenged to get a 2 wide stream into the opening.

Opening can be wider 28" - 24" with shorter 2' bot feeding easy 4 or 5 across also same for shooter

[Cothron Theiss]

Originally Posted by SenorZ

I'd love to see a continuous stream of balls flying out of a drum!

Consider the power consumption. The balls are pretty light, but trying to pull several up from the bottom of your hopper with enough speed to propel them 5+ feet in the air, all using the same mechanism is going to be challenging.

I might be wrong, but I still think you're misunderstanding the OP's intentions. I think the OP is asking about just using a large, wide flywheel capable of launching more than one ball at a time, not using the drum that contains the Fuel to also launch it.

[AdamHeard]

Originally Posted by Boltman

Opening can be wider 28" - 24" with shorter 2' bot feeding easy 4 or 5 across

He's talking about the goal dimensions, which doesn't change with robot size.

Also not sure how you get a 24" opening on any legal robot.

[Boltman]

Originally Posted by AdamHeard

He's talking about the goal dimensions, which doesn't change with robot size.

Also not sure how you get a 24" opening on any legal robot.

Hey Adam ,

Max volume X,Y is 40X36 6" bumper x2 (-12) = 24 or 28 in theory with a custom drive base, if that's a good idea another story.

I was thinking intake now that I re-read that again

[AdamHeard]

Originally Posted by Boltman

Hey Adam ,

Max volume X,Y is 40X36 6" bumper x2 (-12) = 24 or 28 in theory with a custom drive base, if that's a good idea another story.

I was thinking intake now that I re-read that again

You're forgetting the width of the bumper segments on each side at ~3.25" each.

[RoboChair]

Yes, Drum Shooter.

[viggy96]

Originally Posted by SenorZ

I'd love to see a continuous stream of balls flying out of a drum!

Consider the power consumption. The balls are pretty light, but trying to pull several up from the bottom of your hopper with enough speed to propel them 5+ feet in the air, all using the same mechanism is going to be challenging.

I was more thinking along the lines of having a drum after the loading conveyor. The conveyor would be low speed used for loading the hopper and transporting the balls up to the high speed shooting drum.

[Kevin Sevcik]

Originally Posted by SenorZ

I'd love to see a continuous stream of balls flying out of a drum!

Consider the power consumption. The balls are pretty light, but trying to pull several up from the bottom of your hopper with enough speed to propel them 5+ feet in the air, all using the same mechanism is going to be challenging.

Okay, 74g ball. Call it 8 m/s muzzle velocity. Let's assume rolling without slipping out of the shooter, we'll call it a ring so I don't have to look up inertia of a wiffle ball. So 1/2mv^2+1/2mr^2(v/r)^2. So r cancels and mv^2. Each shot has about 5j. Yes inefficiencies and all that. Say 10% efficiency, so 50j per shot. A properly geared CIM would put out 334W, so 6.5 shots per second without slowing. So with those assumptions, a 2 CIM drum shooter could put out 13 shots per second without slowing.

[pipsqueaker]

Drum shooter is absolutely the way to go (unless anyone can design a high-capacity catapult, 1678?)