pic: Top Gun Team 1294 Teaser


Old school ball harassment device. Or, what do you think it is?

A jail for naughty balls!

Plinko played with POOF balls instead of chips?

I do think it looks like a big pachinko machine, without the garish paint job.

HMMM 3 drills and blocked in poof balls.HMMMM It’s a POOF ball torture device.

That looks nearly identical to the design I am trying to convince my team is a good idea. They’re stuck on a stupid hopper.

Tell them they’re wrong. It works like magic, even without bearings on the shafts, and with some mathematic relationships that need tweaking. I haven’t timed it, but it can move a half-dozen balls up from the bottom to the top faster than a human can feed balls into it. Tomorrow we are adding the prototype shooter to the top and hooking up the prototype scooper to the bottom (sort of). Then, the fabrication team has to replicate it in more primitive materials like aluminum and lexan.

But plywood is so awesome on robots… But I guess shiny usually always wins out huh?

Well, what this thing is used for is feeding balls from the bottom of the hopper up to the shooting wheel. Sorta like this:

./…<—adjustable angle firing thingy
|…O_…<—firing wheel

…O…|…<—feeder roller (made out of 3/4" hollow aluminum tube and pool noodles)

Ya, sorta like that. I had planned to have a continuous ramp thingy, but my dad decided to try it without the plywood over the dowels and it worked great. I had also originally intended just one feeder roller, but that didn’t get enough height past the base of the hopper so my dad suggested another S bend with 2 more rollers, and it works well. It maintains about an inch of compression on the ball all the way up. The reason it feeds from the bottom is to allow the angle adjuster to rotate around the firing axle without being limited by a gravity feed-tube coming from above or the side. Anyway, I hope this helps your design or gives you a few good chuckles.

How many balls can fit in there at one time?

And… what is driving the balls? Is that foam noodle material I see? (the yellow)

Robotaddict is my son. He designed it and I helped him build it.

The loader holds seven balls internally. He wants to use a sensor (TBD) to pulse the single feeder motor just enough to load one ball to the shooter each time the firing button (TBD) is pressed. Behind the loader will be a narrow (one ball thick) hopper which will hold another 8-10 balls fed by a one-ball-thick scooper across the back of the bot. We are big on one-ball-thick designs since we know that any other configuration would lead easily to ball jams of squishy poof balls.

Making rollers out of thin-walled 3/4-inch aluminum inserted into pool noodles was my contribution to the design. They are ultralight, cheap, and strong enough. The 1/4-inch steel axle pins in the ends are heavier than the whole rest of the roller. We might wrap the noodles with a rubber surface (something like a bicycle innertube slit open and wrapped around it) to improve grip.

Cheap and effective – two words that should be the FIRST slogan.

Thanks for the prototyping idea with the drills. That should save my team a day or two in making up its mind about ball mechanisms. I’m pushing a similar design with conveyor belts between the rollers.