May bumpers move?

[tinymoonrocks]

Are bumpers allowed to move?
I've been reading the manual for anything addressing mobile bumpers but I couldn't find anything. By mobile bumpers I mean so with wise not horizontally (side to side) allowing for something in between the bumper and chassis to absorb impact. Technically the bumper will still be crafted to regulations and it will be attached rigidly to a mount on the chassis (complying to the rules for bumpers) only that mount would allow movement according to impact.


HELP!?:confused:

[mathking]

now here's the tough question:

What if you have a fractal bumper on one part of your robot's perimeter, giving it infinite perimter. That way you wouldn't have to cover the rest of your robot in bumpers and you would still be legal (infinity/(infinty + constant) > 2/3)

................jk ;-)

The real question here is what size of infinity? If it is a small infinity in the numerator and a larger infinity in the denominator then you get effectively zero. Reverse that and the bumpers cover more than the length of the perimeter. :D

[Russ Beavis]

Mobile bumpers have not been explicitly declared to be illegal in any rules or Q&A responses (to the best of my knowledge). Be VERY careful, however -

1) bumpers must be mounted to a solid structural element in your robot and not a flimsy actuator
2) the bumper perimeter must ALWAYS be at or beyond the reach of every other part of your robot
3) you need to protect BOTH sides of EVERY vertex in your bumper perimeter and the corners can never have any "hard" parts.
4) bumper perimeter must always stay within the 28"x38" envelope.

You should consider posting a question on the FRC Q&A regarding bumper mounting to additional "shock absorbers" within your robot. Rule R08-G (ie #1 above) requires that the bumpers be "tight" and "robust" in their mounting to the robot structure. Regardless, why bother with the complexity associated with something intentionally moving under impact? I could imagine some interesting uses of the extra energy but I'm skeptical.

Also, I have trouble imagining a corner that moves and still fully complies with #3 above.

Russ

[EricH]

Mobile bumpers have not been explicitly declared to be illegal in any rules or Q&A responses (to the best of my knowledge). Be VERY careful, however -

1) bumpers must be mounted to a solid structural element in your robot and not a flimsy actuator
2) the bumper perimeter must ALWAYS be at or beyond the reach of every other part of your robot
3) you need to protect BOTH sides of EVERY vertex in your bumper perimeter and the corners can never have any "hard" parts.
4) bumper perimeter must always stay within the 28"x38" envelope.

You should consider posting a question on the FRC Q&A regarding bumper mounting to additional "shock absorbers" within your robot. Rule R08-G (ie #1 above) requires that the bumpers be "tight" and "robust" in their mounting to the robot structure. Regardless, why bother with the complexity associated with something intentionally moving under impact? I could imagine some interesting uses of the extra energy but I'm skeptical.

Also, I have trouble imagining a corner that moves and still fully complies with #3 above.

Russ
Russ is once again correct. I've seen 3 Q&As (http://forums.usfirst.org/showthread.php?t=11128) addressing (http://forums.usfirst.org/showthread.php?t=10983) movable bumpers (http://forums.usfirst.org/showthread.php?t=11259), and they are allowed provided that all other considerations are met. The fun part is the corners, though.

[mrnoble]

hold on- the bumpers must stay within the 28 x 38 perimeter?

never mind- see what you're saying. The "bumper perimeter" is the maximum dimensions of the robot. The bumpers can extend a max of 3 1/2 inches beyond the perimeter (1 inch for the hard back). whew. just panicked for a mo'.

[GaryVoshol]

I agree. While there is no rule directly against it, I think it is a practical impossibility. If you move either a whole side of a robot or a partial side of the robot, you create a gap in the bumper perimeter, meaning at least one corner is not protected on two sides.

[Tristan Lall]

Regarding corners in flexible bumpers, you could install a series of short bumpers on appropriate structural backing, with door hinges between them. That would at least allow some freedom of motion.

This year, the elements of a "multi-part attachment system" that remain permanently attached to bumpers can be counted as part of the bumpers—this would probably qualify.