Prototype ball launching system. Delta bench sander, Porter Cable 361 belt sander, various scrap lumber, and some drywall screws – VIOLA! Or voila. Something like that. Anyway, the project took two hours.
The belts run at about 4mps, and the ball goes a maximum of about 4 meters. You’re going to want to go for the full 12mps max velocity.
Congrats for being the “first” FIRST ball launcher.
This technology brings up an interesting question;
What if team “redabot’s” ball launcher scuffs-up the balls enough to not function properly with team “bluabot’s” mechanism?
There can only be a modest amount of ball inspection and that could only possibly take place in-between matches.
Rules on accidentally or intentionally messing-up the balls?
I’d guess that FIRST will not try to inspect balls for damage to surface finish, scuffs, scratches, and so forth. Between matches they may try to replace balls that have chunks missing.
Generally, has GDC has expected teams to design gamepiece interaction mechanisms that are robust enough to deal will minor variations in gamepieces. <G20> doesn’t explicitly mention balls – that is probably not an omission by the GDC.
We talked about this at our local kick-off event. We decided two things:
A ball scores if at least 50% of its mass gets through the goal.
Using 36 grit belts to launch the balls would be a Bad Thing.
The AC-powered test unit is using 150 grit sanding belts.
not to sound negative, but i think the first FIRST ball launcher was revealed in 2002 when the CIM motor was introduced to teams…but back to the post…was the orientation you have it in now the way you tested firing, or did you use any kind of angle on it??
as far as getting the balls dirty or scuffed…no need to use a belt sander for that…did you all see the balls in 2002 after competitions? they got scuffed and marked on their own, and i would plan on have “minor variations” in game pieces because what i remember the balls in 2002 started almost sticky, but by the end of the competition they were very smooth from all the dirt that accumulated.
Well, you’re the enemy of fun, aren’t you?
…but back to the post…was the orientation you have it in now the way you tested firing, or did you use any kind of angle on it??
The gray toolbox in the pic is a crucial part of the elevation system.
as far as getting the balls dirty or scuffed…
In our highly-sophisticated testing lab (which looks a lot like my garage/shop), the balls collect dirt better than a Swiffer duster. I’d make sure all the ball-handling surfaces you use have a really high coefficient of friction. I’m seriously thinking of using 1-inch sanding belts in competition.
Aaaaaactually…
The first, FIRST ball launcher was unveiled in 1994 on the famous Sunny Delight robot. This robot went on to win the National Championship that year.
-JV
I can’t wait for a sandpaper-powered ball launcher to get stuck and go up in flames…Ah, the smell of melting Poof balls.
Hey, each team needs a safety officer. Sounds like 'bot carts should carry a manditory fire extinguisher.
Either that or an “air raid siren” for incoming ejected high-velocity Poof balls…
We still have that machine running! :yikes: Although until Saturday it was in storage…
pic i posted in 2002, of the launcher.
2 questions…
1 - how much surface damage is that doing to the ball?
2 - how fast is that shooting?
Very nice! But, I think the thread title should at least be second FIRST ball launcher*, seeing as how This Post appeared on Sunday…
*for 2006
Don
The one in the pic above was also finished on Sunday, I just didn’t take pics until Monday. Tie?
1 - Essentially none. The sandpaper is fine grit.
2 - About 5 m/sec. Sanders have LOTS of torque, but they don’t run super-high belt speeds.
