Underestimating the Trailer

[Petey]

Originally Posted by EricH

I don't think so. The contact is to be bumper-bumper instead of bumper-tongue (<R18>E) and the hitch is to be on the outside edge of the robot (<R18>D) and the the trailer must be easily removed after the match by removing its pin (<G36> and <R18>C).

It's possible, but it'll be pretty hard. You also have <R08> to consider, which includes the bumper perimeter.

I bet it'd be hard, but I'm pretty sure it's possible. You don't need a square chassis, all you need is a way to construct your back end in such a way that the sides of the hexagon abut the back end of your bot while the trailer tongue is pulled pretty far in while also observing the other rules about attaching easily and not hitting the walls before bumpers.

e: what's the shear strength of the bolt?

[EricH]

Originally Posted by Petey

I bet it'd be hard, but I'm pretty sure it's possible. You don't need a square chassis, all you need is a way to construct your back end in such a way that the sides of the hexagon abut the back end of your bot while the trailer tongue is pulled pretty far in while also observing the other rules about attaching easily and not hitting the walls before bumpers.

Bumper perimeter is defined as the outermost polygon in the bumper zone. However, you only need 2/3 of it. I'm sure you could come up with something like that.

[kirtar]

Originally Posted by Petey

I bet it'd be hard, but I'm pretty sure it's possible. You don't need a square chassis, all you need is a way to construct your back end in such a way that the sides of the hexagon abut the back end of your bot while the trailer tongue is pulled pretty far in while also observing the other rules about attaching easily and not hitting the walls before bumpers.

e: what's the shear strength of the bolt?

Just remember that the hitch has to be on the bumper perimeter. Even if you put an indentation, the outer vertices would still define a polygon which would put your hitch not on the bumper perimeter.

Also, to EricH, you only need bumpers on 2/3 of the bumper perimetier. The entire bumper perimeter exists whether on not there are bumpers on the robot.

[EricH]

Originally Posted by kirtar

Also, to EricH, you only need bumpers on 2/3 of the bumper perimetier. The entire bumper perimeter exists whether on not there are bumpers on the robot.

That's what I said. You only need 2/3 of it (the perimeter). Though maybe I should have added "covered" to the end.

Also note, though this is not official by any means: the trailer hitch will (most likely) take up 7" of the 1/3 uncovered. I don't think the GDC will rule that it's a bumper...

[GaryVoshol]

Originally Posted by EricH

Also note, though this is not official by any means: the trailer hitch will (most likely) take up 7" of the 1/3 uncovered. I don't think the GDC will rule that it's a bumper...

More than that - you've got to have a big enough gap in your rear bumper so that the trailer tongue doesn't hit the edge side of your bumper.

[Ziaholic]

Originally Posted by GaryVoshol

More than that - you've got to have a big enough gap in your rear bumper so that the trailer tongue doesn't hit the edge side of your bumper.

According to some "back of a napkin" math we performed, the 7" is an adequate bumper gap if you are in the "wide" formation and have the remainder of the 38" covered in bumpers.

The trailer/bot bumpers should contact before the trailer tongue touches.

[silicon_ghoti]

Originally Posted by Petey

I bet it'd be hard, but I'm pretty sure it's possible. You don't need a square chassis, all you need is a way to construct your back end in such a way that the sides of the hexagon abut the back end of your bot while the trailer tongue is pulled pretty far in while also observing the other rules about attaching easily and not hitting the walls before bumpers.

We were looking into that too, but our team came to the general consensus that FIRST was trying to articulate that the trailer hook-up was to be attached to the "outer-edge" created by the bumper polygon. For those curious about the bumper polygon it is shape created by the outermost points/corners of the robot. (Note, by definition polygons cannot have indentations, or in other words internal angles greater than 180 degrees.) But I would love for someone to prove us wrong.