Can I use a ball shooter to shoot at the enemy robot to knock them off the platform/ keep them from coming on the platform
maybe, but if your ball shooter is powerful enough to do that, you should allocate your motors to somewhere else on your robot. A ball shooter should at most maybe rattle the lift
** And you might be breaking several rules. Balls powerful enough to push a robot off are definitely powerful enough to hurt someone. Considering that its a shooter that really isn’t safe. **
If you really want to know, ask here for an official response from the GDC.
No, please don’t ask any official anyone. The idea is clearly illegal and clearly infeasible.
If something is illegal, please cite the rule. This is a forum where people come to learn, so we should point them at what they’ve overlooked. Link the rule book and quote the rule. Just help people learn.
Edit: people misunderstood me. I wasn’t trying to say it wasn’t illegal, just trying to encourage people to show why they’re saying what they are.
Well <G2> for one. <S1> also would like to have a talk with you.
Set your robot on the platform, and grab a ball and throw it at the robot as hard as you possible can. It’s not going to be moved off the platform. Think about how much it would hurt to be hit by that ball you just threw. Now think about how much harder the ball would actually have to be thrown to push a robot off the platform, and then think about how the ball traveling at such a speed could injure someone.
<G2> Common sense.
Actually probably <G12> Don’t destroy other robots. Because if your robot is strong enough to push a 15 to 20 pound robot off the platform, it could damage a cortex or V5, sensors, or other parts on a robot if misfired directly at one of those items. Not to mention completely destroying the flags, nets and other field elements. And hurting audience members, refs, and other competitors.
common sense always applies
@tdrees Actually, this is a really interesting idea. I’ll try this in my next competition and see if it works.
/s
I believe this will probably come down to the decision of the referees on whether or not this action was based on malicious intent or based on defense of the center platform accordingly with <G12>. They will most likely rule it on which type of intent is more evident.
I’m simply telling him that he won’t get an official response from VEX here. You also say this is “clearly illegal and clearly infeasible.” but have no reasoning behind why this is so obviously illegal.
You would be battling against several rules.
First, <G12> is obviously a problem. You would be damaging a robot undoubtedly if you had that much power behind the ball. However, <G12> is waived on the top platform. The problem is, it says:
If you are just shooting them off the platform, and not attempting to get on the platform yourself, this would be illegal. And <G2> still applies here.
That being said, I doubt a ball would actually be able to move a robot that far without breaking the ball, or at least damaging it, which is also against <S1>
If you have a puncher that powerful it would have a good chance of hurting someone aswell, should it miss, ricochet, or turn into shrapnel.
Last, you have the best rule of all, <G2>. Common sense says that you shouldn’t turn the field elements into a weapon for removing the opposing alliances robot from the top platform.
In my opinion: It would be illegal. Unless it is otherwise stated, I think any ref would warn or DQ you for using this strategy. Like I said before, if you want, you can ask on the official Q&A, which is made for clearing up questions, as obvious as they may seem. If you sincerely believe that this may be legal and do not agree with everyone’s rationale against it ask on the Q&A. But if this is just a joke post, or you don’t believe you can even do it, please don’t ask them.
Unless it is specifically said that it isn’t illegal by the manual or official Q&A, it is safe to assume that it is illegal.
It’s one thing if you’re shooting balls to jam a component (like the drive [shooting at the base of the bot so it runs over the ball, for instance] or launcher [while they’re shooting or loading]) of the other robot, but it is another thing entirely to shoot with the purpose of forcing the other robot to move or stop entirely. The latter is simply unsafe. The former might even have some ambiguity in the rules, so it would not be smart to push this strategy.
Actually… I thought this has already been covered under this q&a?
https://www.robotevents.com/VRC/2018-2019/QA/15
So as Long as the mechanism will potentially damage opponent robots, it will not be legal.
I would presume that a shooter that is strong enough to shoot a ball/cap to dislodge a robot from the platform will be potentially strong enough to damage a robot as well.
Sorry about my earlier post, I was mostly trying to protect the Q and A from clutter but I can see why it wasn’t helpful. My apologies 
Here are 4 different rules I found in the rule book that make this strategy illegal.
But, just to go the extra mile (and because I’m super bored waiting for v5 to ship) I decided to test out whether or not this strategy would actually work by using my robot as a test dummy. I pulled the drive shafts out of the motors to make the wheels free spinning, I bolted a several large pieces of steel to the back of the robot to protect it, and I placed the 15 pound robot + shield onto 2 strips of low friction lexan on my driveway. Then, I threw a ball at it as hard as I could. This was the result.
I was a little league and pony league pitcher for 5 years and I learned how to get the most speed out of my not particularly huge body. I’m estimating the ball was traveling between 70 and 80 mph. But even if we assume it was traveling at 60 mph (the speed I could throw when I was 13), the robot moved under 1.5 inches. This means that, in order to move a robot 9 inches, which will most likely move the center of gravity past the edge of the parking platform and push the robot off, the ball would need to be traveling at 60*(9/1.5) = 360 mph. And this is assuming the opponent’s robot is nearly traction-less and doesn’t have any sort of a parking break.
I think it’s safe to say your best bet is pushing with your drive 
@Anomaly the speed that you would need to throw the ball at isn’t linearly correlated to the distance you need to make the robot travel. Think braking distance for a car (proportional to kinetic energy, which is proportional to distance^2), so you wouldn’t actually need to throw at 360 mph. Somewhere only around 150 miles per hour would suffice, if I can do math.
You right you right.
But if we’re talking anything over 50 it’s definitely a safety hazard
Yea I was just messing around
For that matter, isn’t everyone on this thread messing around?
I am
Amusing thoughts. Another related issue: will the ball survive striking a roughly 20 lb robot while traveling at 150 mph? Might have to fire it even faster to deal with that. Also, make sure you deal with recoil, as your own robot may well get knocked over - maybe set up pressed into a wall to help?
Well it’s against S1 to damage field elements, and it’s pretty likely you would damage if not destroy the ball. Additionally since you arent actually be trying to get on the platform, as you are up against the wall, the G12 exception doesn’t apply.