Expansion exploit possibility?

Since I haven’t registered yet, I’m having to ask the community instead.

If I start out with a robot that is 18” tall, and when I leave the expansion zone and I go up the platforms, will my robot be considered taller than 18” when it’s slanted while climbing up?

If it isn’t considered taller than 18” when the robot is slanted upwards, couldn’t I possibly make my robot tilt upwards towards the high flags with some sort of tilting mechanism and reach out to the same height of the high flags, creating a defensive barrier?

I feel like when the manual says a maximum of 18" tall it means 18" tall relative to the bottom of the robot, not the floor

Don’t worry about that. The 18 inch rule means that at any point, if your robot is OUTSIDE the expansion zone, it must be 18 inches tall. That is the robot height, regardless of field elevation.

However, you can not elevate yourself on a wedge, as that would be expansion outside the expansion zone.

So I must make my robot be less than 18” height to be able to tilt up probably…

We’ll probably need to ask for clarification because in the recent past is has been relative to the floor. That was why you could be violating the rules if your robot fell over while expanded to be tall.

I quote R4 since it determines how robots are sized with the on-field sizing tool.

If you drove your robot onto a cap or ball then you might be able to do this.

…Or make your robot shorter than 18" height-wise wink wink

Your robot must start the match in an 18" by 18" by 18" cube and when not in the expansion zone it can not be any taller than that. In my opinion, if, while driving upon the ramp, a part of your robot is now more than 18" above the floor, then you are NOT in violation as your robot is still 18" or less in height. If you passed inspection, and don’t expand vertically beyond the inspection limit of 18", then you remain legal anywhere outside of the expansion zone.

If the tilting mechanism is part of the robot, then your robot would be greater than 18" and in violation. There is a difference between the height of the robot when driving over a field object and using a part of the robot to tilt.

The lower high flags are 32" off the ground. To reach that height you’ll be very close to breaking the horizontal expansion rule, if as you say, this tipping wouldn’t break the vertical expansion rule. Your third dimension can only be about 16" before you’ll break the 36" expansion rule. You can’t physically block the tallest row of flags.

You can NOT tip, using a part of the robot pushing against the floor, in such a way that any part of your robot is more that 18" high outside of the expansion zone. For example, if I have an 17.5" tall robot and I extend legs down that lift a corner of my robot (tilting it), as soon as any part of my robot becomes taller that 18" as measured from the surface that the robot is on, I am now in violation. If I had a 32" wide and 5" tall robot and tilted it in the manner above, as soon as any part of the robot becomes greater than 18" tall, measured from the surface that the robot is on, then I am in violation. In these two cases, the robot is itself expanding beyond the 18" height limit outside the expansion zone.
The only legal way to have part of your robot more that 18" above the floor tiles outside the expansion zone is to be on a platform, in which case your robot height is measured from the surface of the platform or if your robot has driven onto a field or game element, causing it to tilt in such a way that a part of the robot is now more than 18" above the floor. In either of the above cases, the robot itself did not expand beyond 18", it is merely the position that the unexpanded robot is in.
To me the best way to think of it is as follows: when the robot was inspected, it had to be inspected in the position that you would place it on the field at the start of the match. That then defines the plane that the robot sits on. Outside of the expansion zone, a robot cannot extend above 18" above that defined plane. so in driving up onto a platform, it is expected that a corner of the robot might be greater than 18" above the floor.

The horizontal expansion is only concerned with horizontal dimensions and not necessarily the length of the robot. If you expand horizontally while tipping, starting about 30 inches from the flags, an 18" wide robot could be almost 45" long and still not be outside the horizontal expansion limits. To answer the original question though, I think the GDC will rule expansion while tipping illegal, but if you just drive your robot over a field element you should be good.

Why is that? You’ve already noted the exception for the platforms. If I build a robot that can jump while never expanding to more than 18" tall, how would that violate the height rule?

How do you get that??? If you fill the maximum size allowed outside the expansion zone, your robot is a right cylinder with a diameter of 36" and a height of 18". The longest distance across that cylinder is 40.25". Even then, realize that that length between the points you care about won’t reach nearly that distance.

This year’s manual uses the same wording as last year’s in reference to horizontal expansion. In this threads of last year’s Q+A (https://vexforum.com/t/answered-sg14-ambigious-wording/42639/1) they established that the wording meant that no two points viewed from a top down perspective could be more than 36" apart. So a right 36" diameter cylinder is illegal. also, as a robot tips its top down profile length decreases so the robot itself can be longer than what would be legal if the robot were flat.

EDIT: Alternatively, you could think of it as saying that the horizontal distance between any two points cannot exceed 36" so if the vertical distance can legally be greater than 18" through tipping, then the net distance between those points can be far greater than would normally be legal. My calculation of 45" was based off of a scenario where a flat robot 45" long and 18" wide is tipped up to a height of 32 inches from 31 inches away. which makes the diagonal of the robot about 48 inches even though it’s still technically legal.

I agree. I was just saying that if what he was saying were legal in terms of avoiding the height expansion limit, it still wouldn’t be able to work effectively, because then the horizontal expansion would be violated because if your height limits move with the robot, then your horizontal limit would have to as well. .

Ok, but then you’re violating the height limit. My point is that if your vertical height measurement point moves when your robot tips, then your horizontal expansion would also have to. I don’t think that your vertical height does move with your robot, but even if it did, the defense that was suggested would still be illegal.

There is quite a bit of difference between tipping and jumping. I agree that, IF you could jump without violating the 18" rule, you would be perfectly legal. I was merely referring to a mechanism that remained in contact with the floor that tipped one side of the robot up as I interpreted what the person to whom I was responding was saying. As for the jumping, I would love to see it.

A robot 45" long is already 9" outside the maximum horizontal expansion, so NO, not technically legal.

36" is for horizontal dimensions. a 45" long robot tgat is tilted up at a 45 degree angle has a horizontal dimension of 31.82" which is legal.

I did not give an exception for the platforms. An 18" tall robot sitting on the field is still an 18" tall robot sitting on a platform. Yes, the top of the robot is now more than 18" above the field tiles, but relative to the platform it is sitting on (and is not part of the robot itself), the robot is still only 18" tall. And if in the act of driving onto the platform, part of the robot happens to be more than 18" above the floor, I think that will be allowed as the robot height is determined from the plane it rested on at inspection. That plane tilts as the robot drives onto the platform, so the robot itself has not expanded.