54 in cylinder

For the 54in cylinder rule, does the base of the cylinder stay parallel to the ground if the base of the robot is not parallel with the ground (i.e. when the robot is trying to climb the pyramid).

Rules R03 and G23 specify the projected cylinder is horizontal, with a very clear picture of a robot enclosed in a figurative cylinder with its bottom base mashed against the ground and the top face parallel with the roof of the arena.

For future reference, FRC doesn’t like it when you lawyer the rules, so I would avoid it. The spirit of the rule is made very clear with both the diagram and repetition of the rule.

Good Luck!

The way I have read this, is that the 54 inch cylinder applies to the area parallel to the bumpers while on the ground. Hence the penalties for tipping.

I find myself seeing a submission to the Q&A. I do not think it is clear as to whether the cylinder tilts with the robot or remains perpendicular to the floor. That distinction can affect how one designs a mechanism to operate.

I’m going to politely disagree and say that I wouldn’t consider this lawyering, especially since this is probably the 10th time I’ve seen this question asked since Saturday and the answer to this is a make-it-or-break-it for a lot of design constraints. Something like “is it legal to do this really complicated maneuver because rule <J33> technically doesn’t say it applies when you’re on the same alliance”…that’s more like lawyering.

Fair enough. I thought this was a rule brought over from 2012, but it’s more of a modification of the 14-inch rule to go along with the new frame perimeter, and now I just look belligerent.

I believe the base of the cylinder would tilt with the robot, because otherwise, a legal 60 inch tall robot would stop being legal if it were at a certain angle relative to the ground (unless this is intended, in order to force taller robots to design around this extra constraint).

Seeing rules extremely similar to this one being put to use through previous years it would lead me to believe that the cylinder would stay flat on the ground. For instance, back in 2008, if you fell over while trying to hurdle the trackball and your robot had to extend itslef to put the ball over, you woulod incur the “too-big” rule.

For those unsure, ask in the Q&A. Personally, I believe the rule is very clear:

A ROBOT’S **horizontal **dimensions may never exceed a 54 in. diameter **vertical **cylinder.

You can’t lawyer the word “horizontal” or “vertical”. My dictionary defines both as being in relationship to the ground.

Horizontal: “at right angles to the vertical; parallel to level ground.”
Vertical: “being in a position or direction perpendicular to the plane of the horizon; upright; plumb.”

I guess what might be troubling them is what viewpoint are the rules looking at? Robot-centric or Human-centric? If it is from robot, then the cylinder obviously tilts with the robot; if it is from human(which I think it is) then it stays on the ground even if the robot tilts.

Horizontal and vertical are with respect to the field. For reference, the carpet is horizontal; the alliance station walls are vertical. FRANK the robot shown in <G23> is tilted, but the cylinder is still based from the floor.
Horizontal is horizontal, vertical is vertical, regardless of the robot’s orientation.

The view point doesn’t matter. Horizontal and vertical are constants, defined with respect to level ground. If you lay on your back on the floor, do you suddenly say that the floor is vertical and the walls are horizontal, just because your perspective has changed?

Laying down and looking out of your own eyes, then yes the floor is now vertical and the walls are horizontal because that is your perspective. But looking at it in the perspective of someone else looking at a robot, then no it never changes because your perspective isnt changing when the robot moves.

This needs to be asked in Q&A, because FIRST has ruled differently in different years. In 2008, the cylinder was vertical regardless of robot orientation, but many years they have ruled that incidental excursions due to transient conditions such as tilting or being off-balance was not a violation of the rule. With the variety of hanging styles I expect to see this year, clarification is necessary. Would a robot be penalized if it briefly swings outside the cylinder during a winching process from the 1st to the 2nd level of the pyramid? How would that even be determined?

The BUMPER ZONE is also ruled a horizontal plane, but last year they had to modify it to be in relation to the robot’s stable driving orientation because of bridges and barrier crossing. I expect a similar interpretation may be necessary this year due to climbing rules.

Interesting thought, as when a similar field vs. robot question was asked on the Q&A last year, the response specifically defined “vertical” as in relation to the robot. In fact, virtually all such questions with regard to both orthogonal axes were deemed to be in relation to the robot that year, and in several others I can remember offhand.

Note that this is not to say that 2013 will be the same as 2012 or any other year, only to point out that the GDC has written in similar ambiguity in the past and ruled it robot-centric. It was really the only logical approach for many of the 2012 questions; this is significantly more ambiguous.

The two rules were written quite differently:


Robots may extend one appendage up to 14 in. beyond a single edge of their frame perimeter at any time.



A ROBOT’S horizontal dimensions may never exceed a 54 in. diameter vertical cylinder.

In 2012, they defined the constraint with respect to the robot - 14 inches past the frame perimeter. This year, it’s defined with respect to horizontal and vertical, which I take, by their very definitions, to be constant with respect to a level floor, which is another way of saying constant with respect to the local gravity field - for all practical purposes, they don’t change as the robot orientation changes, for all games played here on Earth. If you play a game out in the middle of space, you might have a different answer :p.

I do not believe that anyone referencing 2012 is referring to G21 (certainly I’m not). The questions last year were almost all about the allowable height and width with respect to the floor while you were on the bridge or barrier. Numerous Q&A questions on these subjects even led to updating the manual wording itself. This year’s situation, where again the robot is expected to climb an inclined object/traverse a barrier, are quite similar in that respect.

I believe that its relation to the robot but this question has been brought up by my team members.

This has been answered in the Q&A Q15:

The vertical cylinder specified in G23 is not coupled with the ROBOT’s orientation and is always vertical.

This is highly worrisome. What if you are a 60" tall robot and you are tipped over (maybe you fall off the tower). Do you get a technical foul? By this ruling, yes, absolutely you do. I feel like that would be adding extreme insult to injury, though and I doubt intended.