Pic: would this chassis shape be legal?

[gburlison]

Originally Posted by Creator Mat

OK my team wants to do something like this (see attached pic) for our chassis shape. we follow the bumper rules. Would this type of shape be legal when herding the balls? I think it is legal because the ball would be free to move within the indentation area and thus would not be possession. I want to find out what the rest of the FIRST community thinks. Also if you think this would break a bumper rule or some other rule beyond just the no possession rule please say something.

Note: the red strip on the ledge thing on the top is supposed to be the bumpers

I don't think this is legal. If you filled in the gap on the part of the frame at the height of the bumpers, it might be a legal frame, but the frame perimeter will include this filled in area and if a ball protrudes more than 3 inches inside this frame perimeter, you may not pass inspection and will incur a penalty if this happens during play.

[ralcony]

I am relatively new to FIRST competitions so maybe this is a silly question butm I thought in the webcast they changed the bumper color by removing a piece of elastic fabric. How could you keep have a break in the bumper and use the piece of fabric for quick alliance color changes?

[EricH]

Originally Posted by ralcony

I am relatively new to FIRST competitions so maybe this is a silly question butm I thought in the webcast they changed the bumper color by removing a piece of elastic fabric. How could you keep have a break in the bumper and use the piece of fabric for quick alliance color changes?

What they did was called out in <R12>. You can have the bumpers be one color, then have a cover in another color. Keep the restraints strong and hidden.

How exactly you do it is up to you.

[Chris is me]

I didn't interpret the wording of "BUMPERS must wrap entirely around the robot" as "BUMPERS need to cover every surface of the BUMPER PERIMETER". Otherwise, why would they specify the minimum six inch bumper length, and empahsize that every corner needs to be protected? Those rules would be completely redundant and unnecessary, unless they assume people were planning robots less than six inches long.

I took "entirely around the robot" to mean 12 inches of bumper on every side and generally as much around the robot as possible. I'll ask the Q&A of course as I'm in the minority obviously and am probably wrong, and will assume so from now on.

[engunneer]

The manual states

100% bumper coverage
fully backed up bumpers (touching frame)
6" bumper segment length
3" ball intrusion max

In short, the proposed design by the OP is not legal on many counts.

the 6" bumper segment length also applies to chamfered corners, not just length and width of the robot.

the robot bumper perimeter (shape of the frame) only has to fit inside the 28x38 rectangle, and follow all bumper rules. Everything else is up to you - hexagon? Octagon? Circle? random 5 sided shape? All legal.

[jonzjos]

I think this would be legal. Frame perimeter follows the same shape as a string. A shallow recess (3" deep) falls inside the perimeter. So this 3" recess is the only zone that you can do any work to the ball (kick, spin, grasp). Of course you can generally herd the ball by pushing it with the bot all you want.

[gburlison]

Originally Posted by jonzjos

I think this would be legal. Frame perimeter follows the same shape as a string. A shallow recess (3" deep) falls inside the perimeter. So this 3" recess is the only zone that you can do any work to the ball (kick, spin, grasp). Of course you can generally herd the ball by pushing it with the bot all you want.

I agree ( FWIW) that this should be legal.