Low quality 2X ball?

[Rob]

Did anyone else notice that the 2X balls this year were much more fragile than simmilar game objects used in the past? I saw so many big balls popped this year that probably shouldn't have been. We practiced with a simmilar size ball from a previous competition and had no problems. At the Quincy scrimmage the weekend before shipping, we popped 2 big balls. We made some critical adjustments to remedy this problem, but I still think that the balls used this year were not robust enough to handle the rigors of the game.

In Quarterfinal 1 match 2 in the Archimedes division we played against teams 60 and 1241. Each of these teams popped a ball while trying to handle it. The deflated rubber on the field became entangled in part of team 60's drivetrain, hampering them for much of the match. This obviously put them at a disadvantage during the match, and their alliance was eliminated in that round.

In one round at UTC we had a 2X ball in our grasp and were trying to cap. A team playing defense against us popped the ball causing us to have to drive across the field to try and get another one. This took up so much time that we were unable to cap and thus lost the match.

I don't know the reasons or methods for selecting specific game objects, but I hope for more robustness in inflatable objects next year. This would allow teams more flexibility in designing mechanismes. It would also make playing defense agains 2X cappers more difficult because there would be less concern about losing the ball due to popping it. How do you all feel about this?

Rob

[Tom Bottiglieri]

While FIRST may not have planned for the 2x balls to pop so frequently, I think it added a nice element to the game. There were some teams I saw who would go and pop the 2x balls every match. Then these teams, who set their ball grabbing arms to "overkill", needed to change their arms a little.

Also, I think it was a good learning experience that shows that in engineering, some variables change that you may not be ready for. Ask Dave Lavery. I mean, just because the mars rover could traverse over terrain on Earth in testing, does that mean it will be able to on Mars?

[Andy Grady]

We were having big problems with popping the balls at competitions this year. When we used the balls we bought, we inflated them to size, and we never popped one while practicing. When we got to regionals, we realized that the balls, though the same size, seemed extremely over inflated. Almost as if FIRST found a slightly smaller ball and inflated it to maximum capacity to reach size. During the UTC finals, we popped a ball at a key moment and it eventually cost us a match and ultimately, very possibly, the championship. Then at the championships, in curie we popped 2 balls in 3 rounds...resulting in a warning from referees that next time we popped a ball, we would be disqualified. Anyone who saw our robot would have realized that we filed down the sharp edges insanely, even before the warning was issued! Luckily that never factored into the rest of our rounds. Of course, ToMMan is right, its the nature of the game for design to be like that...testing will not always equal the actual environment of what everyone is going to see. Either way, I vote for something different next year.

-Andy Grady

[Jessica Boucher]

Well, is this a new supplier? Historians, what caused this change?

[Mike8519]

The ones from a few years ago (2001) were a couple of pounds heavier and thicker.

[Jessica Boucher]

But were they from the same supplier?

[Kyle Fenton]

The doubler balls this year I believe were only recommended to be inflated to 27 inches in diameter, but were pushed all the way to 30 inches. Also the last time we had balls of these size is was 4v0 game, so there was no struggling for the ball back in 2001.

[Steve W]

We noticed that the balls were different when we went to New Hampshire for the first regional. They were harder and smoother without the same ridges. When asked I was told that the supplyer had to change because of stock problems. I also know that FIRST looked at all of the balls we were using and figured that is would be cheaper to buy the more flimsy balls and have them break than buy the heavier better quality balls. This may not answer all questions but might help.

BTW just because you break a ball it doesn't mean that you can't still double with it. A 2X ball is a 2X ball.

[opnickc]

They also seemed to have problems keeping size. Our claw was designed to grasp the 2x ball (at whatever the specified size was) and had no problem doing so, but sometimes the ball was significantly deflated, to the point that we couldn't pick it up (and it didn't help that the refs wouldn't replace it, even after it was so low it fell into the goal rather than sitting on top of it).

[Andy Grady]

Originally Posted by Steve W

BTW just because you break a ball it doesn't mean that you can't still double with it. A 2X ball is a 2X ball.

True, but the major problem is that if it pops, you have to either pick it up, or hope that it will stay on your claw until you can manage to somehow dump it into the goal. Everytime we popped it, it ended up on the floor and we spent a little too much time trying to pick it up off the ground.

-Andy Grady

[RiceRobotica]

During one of my matches at SPBLI, we had pushed the 2x ball out of our mobile goal and it bounced on to a robot on the other side of the goal. It immediatly popped after barely touching that robot and became tangled in the pvc. We also had our own practice ball which popped in between matches. Maybe it was a different supplier. But it definately added to the intensity, in some repects.

[Mark McLeod]

Originally Posted by Mike8519

The ones from a few years ago (2001) were a couple of pounds heavier and thicker.

We popped our 2001 ball as well with our prototype '04 robot.

[Paul H]

Originally Posted by Rob

In Quarterfinal 1 match 2 in the Archimedes division we played against teams 60 and 1241. Each of these teams popped a ball while trying to handle it. The deflated rubber on the field became entangled in part of team 60's drivetrain, hampering them for much of the match. This obviously put them at a disadvantage during the match, and their alliance was eliminated in that round.

Ughh...don't remind me of that match. Everything that could have gone wrong for our alliance did. What a heartbreaker. I personally didn't notice the big balls too much this year, as our robot didn't handle them. However, when 2 popped in one match, I made my mind up that they should be more durable than that.

By the way, don't post anymore, you have 33 posts! It's a good number to have!

[10intheCrunch]

I believe it was because the balls are supposed to be inflated to 24 inches, left alone for 18 hours or so, and then inflated to 30. The rubber has to stretch a bit to accomadate the pressure right out of the box, or at least the ones that we had needed it. I don't think they did this at competitions.

[melmo]

The balls were picked this way on purpose. It adds a dimension to grabbing the 2X balls, making it harder. Clenching down on the ball with huge pnuematic cylinders is not the answer like in 2001. An approach that grabs the ball using a large surface area or multiple points is more desirable. 469 did this very well, grabbing the ball from four points, and they had amazing control of it. The model number of the ball was given and i do not believe there was any mention of it being similar to the one in 2001 at the kickoff.