traction questions

[AlbertW]

M17: robot wheels, tracks, and other parts intended to provide traction on the playing field ("traction devices") may be purchased or fabricated. in no case, will traction devices that damage the carpet or other playing surfaces be permitted. traction devices may not have surface features such as metal or hard plastic studs, cleats, or other attachments. the other surface of off-the-shelf wheels may be modified by removing tread material only. in no case may a traction device protrued beyond the bottom surface of the Ramp mesh. gaining traciton by using adhesives or velcro-like fasteners material is not allowed.

ok... so i've got a few questions:

1. if you have a foam thingy on the bottom of your wheels, and the weight of the robot presses it into the mesh so part of it protrudes through, is that in violation of the rules?

2. i saw a robot last year that used a belt with metal upside-down 'U'-shaped things to grab onto the carpet... that isn't allowed this year, right?

3. our mentor used some polyurethane foam stuff with some traction pattern cut out of it attached to their wheels last year. is that not allowed this year? it says that the outer surface of off-the-shelf wheels may be modified by removing tread material only.

[Kit Gerhart]

Originally posted by Aonic
ok... so i've got a few questions:

1. if you have a foam thingy on the bottom of your wheels, and the weight of the robot presses it into the mesh so part of it protrudes through, is that in violation of the rules?

I suspect there will be a clarification on this one at some point, but I can envision part of robot inspection including placing your robot on mesh like that on the field and a straight edge run under the wheels or tracks of the robot to check for protrusion. This, of course, is just a guess.

[Jnadke]

Originally posted by Aonic
ok... so i've got a few questions:

1. if you have a foam thingy on the bottom of your wheels, and the weight of the robot presses it into the mesh so part of it protrudes through, is that in violation of the rules?

Until further clarification, yes, it is in violation of the rules. If objects are put through the mesh for the purpose of grabbing, the holes could get deformed.

However, this rule is a bit vague, because it doesn't define the maximum extent of the pertrusion. Any circular wheel will pertrude into the opening of the mesh, but only a little bit. My best guess is that most traction material will be fine, they just don't want people sticking a pneumatic rod through the mesh opening to hold their robot's position.

2. i saw a robot last year that used a belt with metal upside-down 'U'-shaped things to grab onto the carpet... that isn't allowed this year, right?

Correct. Carpet-metal interatction is prohibited by the rules. This inclides the ever popular chain-cleat treads.

3. our mentor used some polyurethane foam stuff with some traction pattern cut out of it attached to their wheels last year. is that not allowed this year? it says that the outer surface of off-the-shelf wheels may be modified by removing tread material only.

There's no reason why you cannot use the polyurethane, but you will have to manufacture your own wheels from stock, and then adhere the material to them.