Question on 3pt Scoring

[Joe Johnson]

What is the ruling on a ball that goes into the 3pt hoop, hits the chains and bounces out?

I am sorry that I have not been following the rules. I have seen it happen on the VCU webcast and I wonder what the rule is and whether the rule is being enforced well.

Thanks,

Joe J.

[Collin Fultz]

The ball has to travel down the chute to score since that is where the scoring counter is. So if a ball bounces out...it doesn't count.

see rule G05

[AmyPrib]

Also though, as long as the balls stay inside the center goal (let's say they get jammed, whatever), they will still be counted.
If it bounces out for whatever reason, it won't be counted.

[Petey]

What is the ruling on a ball that goes into the 3pt hoop, hits the chains and bounces out?

I am sorry that I have not been following the rules. I have seen it happen on the VCU webcast and I wonder what the rule is and whether the rule is being enforced well.

Thanks,

Joe J.

As others have said, unless it passes down the chute it is not counted.

FIRST swore the chains wouldn't rebound the balls...but they were mistaken.

--Petey

[Joe Johnson]

As others have said, unless it passes down the chute it is not counted.

FIRST swore the chains wouldn't rebound the balls...but they were mistaken.

--Petey

Yes, watching the VCU regional finals, I think I saw a robot shoot 3 in a row that hit the back of the goal and bounced out -- took the steam right out of them.

Joe J.

[Conor Ryan]

Yes, watching the VCU regional finals, I think I saw a robot shoot 3 in a row that hit the back of the goal and bounced out -- took the steam right out of them.

Joe J.

At NJ i don't think i saw a single shot that was aimed correctly that bounced out. If they are bouncing out then chances are they maybe shooting at an excessive speed, or a really high angle so they may want to check out their exit velocity and slow it down for their own good.

Do you happen to have the match numbers?

[Petey]

At NJ i don't think i saw a single shot that was aimed correctly that bounced out. If they are bouncing out then chances are they maybe shooting at an excessive speed, or a really high angle so they may want to check out their exit velocity and slow it down for their own good.

Do you happen to have the match numbers?

I'd say that at least once during almost every match with a shooter bot, one ball would go dead on in and then bounce off the chains and out.

I doubt they're shooting at an excessive (re: significantly more than 12 fps) speed. Sometimes they were shot too lightly to push the chains apart, it seemed.

--Petey

[EricH]

I feel it's a design constraint, and machines should have been designed accordingly.
So they should have given us the part numbers for the chain, or even the chain itself. You can't design a machine unless you know what you need to allow for.

(As a side note, at our test area, we didn't worry about bouncing out. There was a substantial brick wall about two feet behind the opening, so if you didn't hit it just right, the ball would always come flying out. We worried more about ceiling beams.)

[meaubry]

While watching the web cast, I noticed that balls bounced back out when shooting hard AND soft - seems kind of weird to have a 12 m/s exit velocity if that velocity doesn't match the acceptable entry velocity (upper and lower limits)

I was really surprised by this issue, and it looked like the chains were closed loops in the video - for some reason I had pictured individual strands of chain.

Anyways - here is an interesting item to consider. According to the detailed drawing (link shown below), the chain frame is not symetrical, if assembled incorrectly (back towards the front, instead of front towards the front), the chains would have been closer to the opening than specified - I hope someone checked that because it could account for the balls bouncing out easier at one regional than at the others.

http://www2.usfirst.org/2006comp/Drawings/2006_TFE_CENTER_GOAL_CHAIN_INSTALLATION.pdf

[kjohnson]

I was back-up ball counter on the blue goal at VCU:
Balls were only scored if they stayed in the goal. We had a PVC pipe to prod the balls if they got stuck so they would go down the tube into the trashcan.


One thing I saw was that if teams shot the balls too fast, the first ball would be stopped by the chains but the 2nd ball would hit the 1st and bounce out.
It also seemed like balls shot from an angle stayed in the goal more than balls that were shot straight at the chains.

[Warren Boudreau]

It might help if FIRST shortens the chains a little. That would reduce the number of balls bouncing out. Or lighten the chains. Plastic chains would probably work a lot better.