Rule G32

My brother just told me about this rule and I can’t quite wrap my mind around if our robot design will cause us penalties. Our lower frame isn’t a perfect square but in the front, has a half hexagonal inlet to allow the trailer to come into our robot a little bit, which will allow our shooting mechanism to shoot straight down into their trailer. There will be a lot of bumper to bumper contact with this, but we will not be penetrating the other teams bumper zone. Will this cause penalties?

Well i believe that there is no rule against the trailer. Now if you were to run into a robot yes… but the only rule with doing that to a trailer is that the bumpers on the trailer MUST contact bumpers on your robot. So just bumper the inside… and you should be good!

If any of you guys found out more let me know, but i believe thats all that was displayed. And of course you cant grab the trailer… :smiley:

Based on a lot of posts here and several official Q&A’s, the answer isn’t simple. You may not touch a trailer except bumper-to-bumper, that is clear. You also may not extend any part of your robot outside the BUMPER PERIMETER.

Team Update 2 had a diagram in it showing what the GDC thought was the maximum incursion a trailer could have into a robot frame; based on that diagram you would not be able to enclose a trailer enough to be able to shoot straight down into it.

If you’ve figured out a way to do it without violating bumper rules or robot-to-trailer contact rules, good for you.

Well it’s not exactly straight down, the shooting mechanism does not go past our bumper perimeter but the inlet allows about 1/5 of the trailer to come into our perimeter, which allows us the angle to shoot down into the trailer with a 100% success rate. Since we’re not actually going past the trailers bumper perimeter, will this cause issues?

This sounds to be ok, as long as you don’t violate the bumper-to-bumper contact rules.

I’m hoping that’s the case because we’re done with the frame for our robot and should be starting driving tomorrow. Starting from scratch would be deadly.

Check the QandA with regard to concave shapes carefully,
if you don’t have the required 6 inch sections, with bumpers
attached, you will have to address the issue in your frame.


Thread Tools
01-11-2009, 02:17 PM
Junior Member

Join Date: Dec 2008
Posts: 0
Bumpers and acute corners
In update #2 the robot is a rectangle with the front of the robot allowing for a 26” opening in the center. The two 6” front sections are perpendicular to the side rails and on opposite sides of each other. Would it be a violation of rule <R08-A> if the two side sections were angled 45 degrees towards the center of the robot – still covered with a bumper. Would the bumpers attached to the 6” angled section be considered enough protection to the corners and not in violation of rule <R08-C>?

01-12-2009, 12:08 PM
Junior Member

Join Date: Dec 2008
Posts: 0
Bumpers for Concave Designs
We have a question about exterior corners of the robot that are less
than 90 degrees. For clarification, this is one specific illustration
of this design, but our question refers to these sorts of corners in

It seems that there are four possible ways to interpret the rules about
such corners:

  1. Bumpers must be present on either side of the corner (per this Q&A
    response: Thus, the
    interior angled sections of the robot must have bumpers.

  2. Bumpers must be located on the BUMPER PERIMETER (<R08>). Thus,
    bumpers cannot be present on the interior angled section, as they are
    not part of the convex hull of the robot polygon.

  3. These sorts of exterior corners are not permitted because (1) and (2)
    cannot simultaneously be satisfied.

  4. The interior angled sections of the robot must be padded so as not to
    damage the trailer (preserving the intent of the bumpers in the first
    place), but since they are “bumpers” rather than “BUMPERS”, they are not
    exempt from weight and size withholdings.

Which is the correct interpretation? Thanks.

01-16-2009, 12:28 AM
Senior Member

Join Date: Jan 2006
Posts: 1,664
Re: Bumpers and acute corners
Based on previously provided information, you have correctly concluded that all exterior corners must be protected by BUMPER segments (Rule <R08-I>). Each BUMPER segment must be a minimum of six inches in length (Rule <R08-A), and must be attached to the BUMPER PERIMETER (Rule <R08-L>). Effectively, this means that an exterior corner of the ROBOT can not be at an angle that is more acute than the coincident corner of the BUMPER PERIMETER. It follows that the example configuration you cited would not be permitted.

Can you show where, exactly, it said that in Team Update #2?

I ask this because, in reading through all of the Q&A threads, it is repeated over and over again that the illustrations in that Team Update show particular examples of one way to implement a solution that satisfies the rules. It does not show the ONLY way to do so. The Q&A responses specifically ask that we “don’t try to infer any other conclusions from these specific examples.” I can’t find anywhere that it says that either example in Team Update #2 shows the maximum opening size/trailer incursion possible. I point this out only because we need to be careful not to assume that there are limits where they are not clearly stated, and that we do not accidently communicate to other teams an incorrect assumption about those non-existent limits.



OK, I should have qualified my remarks.

Team Update 2 only notes a “signifcant limit” on the size of an opening for a typical wide-drive flat front robot, resulting in limited incursion by the trailer.

As I said in my earlier post, if the team came up with a configuration that satisfied all robot rules, good for them.

My reason posting a reply to the question was to suggest they look at what they were doing to be sure it meets the rules. We’ve seen far too many examples of things that don’t appear to be in compliance.

Alright i’ve looked at team update 2, now what if you take the front part of the robot and angle the bumpers so that the trailer can go in far enough to shoot the balls in?

Then you don’t have BUMPERS, you have bumpers, and bumpers must be counted in your size and weight.

This is due to the bumper rules: BUMPERs must be on the BUMPER PERIMETER and must protect both sides of any corner of the BUMPER PERIMETER. Moreover, BUMPERS must be 6" long minimum, and must be supported by the frame of the robot along their whole length. (See <R08>, where there are more details.)

Anything that is constructed like a BUMPER but doesn’t meet all of <R08>'s criteria is not a BUMPER and is therefore included in weight and volume. And you still have to meet <R08>'s criteria. See the above-quoted Q&A thread.

Hmm I had a Lunacy nightmare regarding possible conflict between G32 c and e?

<G32,C> If a portion of the BUMPER PERIMETER polygon is unprotected by BUMPERS, any contact by another ROBOT within the unprotected region (including the vertical projection of the unprotected region) will be considered incidental contact and will not be penalized.
<G32,E> .Contact outside of the BUMPER ZONE is not acceptable, and will result in a PENALTY. The offending ROBOT may be disqualified from the MATCH if the offense is particularly egregious or if it results in substantial damage to another ROBOT.

Let me pose the following question:

If contact outside the bumper zone occurs inside the unprotected region of a robot is rule G32, E in force or does this constitute incidental contact per rule G32 C?

As an example, a robot has an opening to scoop up moon rocks. If another robot enters this opening deep enough to strike structure at a point outside the bumper zone is this a penalty situation?

Have I got Lunacy in the brain or is this clear to everyone?

See <G32-C>. The area that is unprotected by bumpers and its vertical projection are incidental contact.

I honestly don’t think we’ll see too much of <G32-E> this year, due to the simple fact that there should be a good 6" of bumpers between robot superstructures in most cases and not being able to go beyond the bumper perimeter.

See <G32-C>. The area that is unprotected by bumpers and its vertical projection are incidental contact. 

I honestly don't think we'll see too much of <G32-E> this year, due to the simple fact that there should be a good 6" of bumpers between robot superstructures in most cases and not being able to go beyond the bumper perimeter.

Eric, we have always assumed G32 C was in force, too. But I am concerned that the contact can be anything but incidental. We have a large opening and with a support bar (say 10 in about ground). An opponent robot can be struck hard and probably damaged by a high speed contact.

Even though G32E seems to say this is ok, G32C doesnt include exceptions so that is where I see a possible conflict. When you think about it, the configuration I’m describing voids the intent of the bumpers. There is an open space where bumpers would normally hit and a solid metal guard above the bumper zone at the edge of the robot waiting to do damage. So, I’m a little concerned.

No conflict here. <G32C> is talking about the BUMPER PERIMETER; <G32E> about the BUMPER ZONE. These have two different definitions. Your BUMPER PERIMETER is within your BUMPER ZONE, but the ZONE extends infinitely in each direction outwards (and even inwards through your robot). Imagine a fog machine puts out a layer of “smoke” that lays between 1 and 7 inches from the floor, extending across the entire arena. That is the BUMPER ZONE. The BUMPER PERIMETER is defined by the outermost corners of your robot within the BUMPER ZONE. It may be as much as 1 to 7 inches from the floor, but only if you’ve got robot pieces from 1 to 7 inches. Most likely the BUMPER PERIMETER is defined by the frame pieces of your robot. The ZONE and PERIMETER exist all the way around your robot, whether or not portions of them are unprotected by BUMPERS.

Your support bar 10 inches above the ground is not inside your BUMPER ZONE. If it contacts another robot outside that robot’s BUMPER ZONE, you could be penalized under <G32E>, and even DQ’d. But <G32C> gives an exemption to this - if the only contact is in the vertical plane directly above the BUMPER PERIMETER, you are OK. If your opening is so large that a significant corner of the other robot could be enveloped by it and now your 10" bar contacts an interior portion of that robot, you are not OK. Design accordingly.

In my opinion <G32E> is a hold over from previous game rules, when robots could have arms extending outward. You would be penalized if your arm went into the other robot’s guts, because that could cause extensive damage to vital components. I don’t expect to see many <G32E> calls this year.

Let me see if I get this… I’m still working on my BUMPER RULE DEGREE…

If we have an opening in our robot’s BUMPER PERIMETER to allow game pieces to enter - with a roller or conveyer for example - then this roller is outside the BUMPER ZONE. Should another robot’s corner enter this opening, and the contact with the other robot is further back inside the robot than the BUMPER PERIMETER, then that contact is illegal.

Since you can’t predict where you will make contact with another robot (could easily be outside BUMPER ZONE - deeper in their robot) you can’t have an opening in your BUMPERS ZONE/PRIMETER that allows a robot to enter.

From what it seems then, most of the chassis/designs that have been shared here on CD are not legal because a corner of a robot could enter the opening.
(816, 1511, 1856, 949, 1712, 935, 842 all have relatively wide openings where contact could easlily be made behind the BUMPER PERIMETER edge of the robot.

Are we all in violation of <G32C/E>?

-Mr. Van

Because it’s a game rule, we’re only in violation if the contact occurs during a game. It’s not illegal to design a robot that is capable of making illegal contact.

As a practical matter, I doubt that this rule will be enforced with the degree of definitiveness that the manual suggests. (“Contact outside of the BUMPER ZONE is not acceptable, and will result in a PENALTY.”)

I don’t believe so. Providing your bar 10" above the floor is in the vertical project of the BUMPER PERIMETER, I believe that any contact within that zone is okay. The rule (<G32C>) specifically states “any contact within the unprotected region (including the vertical projection of the unprotected region) will be considered incidental contact and will not be penalized.” There is no mention of the other robot’s BUMPER PERIMETER.

Ah! I think I get it now. If contact is made at the BUMPER PERIMETER of OUR robot, then we are legal as per <G32C>.

Thanks for clearing it up!

-Mr. Van

This is how I’ve heard this rule interpreted as well