Redirecting with an inclined top

If a bot can position itself at a point where a returned ball will land and use an inclined top to redirect the ball into the bot’s alliance’s zone, would that be considered CARRYING? The incline on the top would not be moving at all and would not be an ACTIVE component. Thoughts?

We’ve been discussing this since Kickoff. There has been no conclusion reached here.

I’ve a strong hunch that this will wind up in the Q&A tomorrow when it opens.

Personally, I think it could go either way.

What if the plane is normally flat, but can be raised to become an incline? Would it be a definite “no” or would it be okay as long as the ball doesn’t contact when it is raising?

Or would this be another Q&A question?

well think of it this way, you need to build a way to keep balls from landing on top of your bot. Otherwise they would be stuck there and thus acquire a carrying penalty. If you design a slant to keep balls from getting stuck then that would be fine. However if it seems like your purpose is not to protect your bot from a penalty but to manipulate the direction of a ball then I would say that would be a penalty. We will find out tomorrow with the Q&A.

If it’s not an ACTIVE MECHANISM (whatever that might be defined as?) then it should be legal.

Thinking about trying to get some of that goal foam…

The GDC hasn’t [yet] capitalized ACTIVE in <G45>. I suspect their definition of ACTIVE mechanism would involve a controllable, articulated, powered feature. I would consider springback of a lexan shield or damping by miracle foam to be “PASSIVE”.

However, I’m not part the GDC, thus my previous statement could just be Bold Speculation. :wink:

Our concern has been that the movement of the robot’s drivetrain alone may be enough to impart “active” properties unto an otherwise inactive robot feature. If the top of a robot is sloped and a ball bounces off of it inadvertently, surely this cannot violate the rules, but if the robot is moving while that happens such that the ball is directed advantageously, is that a significantly different behavior? It’s a weird question.

Especially if “intent” enters into the referees’ decision process on contacting and redirecting the ball. If the robot is in motion when the ball hits above the bumper zone, will the referee need to decide whether the action was incidental or intended? If the ball travels in a favorable direction, was it good driving or good luck? I see this a a potential can of worms. I wouldn’t want teams to be forced to stop the robot to avoid a <G45> penalty, even though if the robot was stopped at just the right place and orientation…ugh!

Is an “active MECHANISM” one that IS moving, or one that CAN move? That would be my question.

The question Jared341 posed is the exact question I would like answered.

Common sense would dictate to me that it would have to be one that “can” move, but not actually moving when contacted by a ball falling from the ball return. Otherwise, it would be impossible to build a robot that could both prevent the landing of a ball resting on top yet also be able to drive under the tower.

How does one go about getting this question answered officially?

I don’t think that this is going to be as big of a deal as anyone is making it out to be.
Sloped tops are almost mandatory since you don’t want balls getting stuck…
I do not think that they would design a rule to penalize someone for bumping a ball of of a stationary slant on the top of their bot…I mean, hey, you can headbutt the ball in real soccer right?

but I still want to know the definitive answer of this…

Well just in general having a sloped top is not illegal, I would love to see them try to come up with a rule against it. but deliberately using it to bounce balls back into your alliance zone probably shouldn’t be an issue either. my expectations is no one would park under a return drop off, so it shouldn’t be a problem if you do it occasionally.

Also, keep in mind, if you use this as a strategy, its also very easy to do the same with the other team’s return, just deflecting them towards yours!


The ball should return to the playing field in the same general area. One estimate I read from a team that attended the Manchester Kick Off was four feet from the base of the tower. Of course, it’s a bit of a scatter plot, but even so, the ball return is ON THE CENTER LINE. If part of a single robot is on or across the center line, no other robot from that alliance can be on or across the line at the same time. Parking and redirecting…being incredibly passive…seems ineffective and would cut the playing surface available to the rest of the alliance in half!

If the top doesn’t move and a robot simply drives underneath the ball return at the right time to redirect the ball…it seems fair to me.

The whole deal about touching or crossing the center line certainly influences strategy.

Thanks for all the replies.

Where does this centerline stuff come from, did I read the wrong rulebook or miss it?

Where do you get this? The center line is for placement at the start. No robot can completely cross the center line in auto period. No other rules reference the center line that I can find.

I wonder… hmmmm…

Ah! No 2 alliance bots can be in an opponent’s ZONE at the same time. We misinterpreted the zone definition…even though it’s pretty clear in the diagram. Sorry for the confusion. The center line cannot be entirely crossed during autonomous mode, but that’s where it ends.