pic: Carmen week1 team 842

[falconmaster]

loading photo ...

[GarrettF2395]

Wow, I am really impressed by your design!
So this is basically an ackerman steering chassis?
How do you plan on implementing the differential?
How many hours have you guys worked during week 1?

[GaryVoshol]

Oh, oh. Check the bumper rules. You can't attach a legal standard bumper to those angled faces in front.

[thehurd03]

Originally Posted by GaryVoshol

Oh, oh. Check the bumper rules. You can't attach a legal standard bumper to those angled faces in front.

They don't have to, The rules say you have to cover 75% (I think) of the perimeter of your robot.

[Jimmy Cao]

Originally Posted by thehurd03

They don't have to, The rules say you have to cover 75% (I think) of the perimeter of your robot.

2/3, but they also must cover all corners.

It looks rather impressive. Excellent progress for week 1! Good job.

[Bongle]

Originally Posted by thehurd03

They don't have to, The rules say you have to cover 75% (I think) of the perimeter of your robot.

I would worry about bumper rule I:

BUMPERS must protect all exterior corners of the BUMPER PERIMETER

in combination with bumper rule A:

BUMPERS must be built in segments, with a minimum length of six inches, and a maximum
length that does not exceed the maximum horizontal dimension of the ROBOT

So if you need to have a bumper on the front (that's the if), it must be 6 inches long and fastened to the hard robot frame, which in the pictured robot's configuration would put it inside the bumper perimeter and thus illegal according to bumper rule L:

The BUMPERS must be fixed to the BUMPER PERIMETER

[falconmaster]

Originally Posted by Bongle

I would worry about bumper rule I:

in combination with bumper rule A:


So if you need to have a bumper on the front (that's the if), it must be 6 inches long and fastened to the hard robot frame, which in the pictured robot's configuration would put it inside the bumper perimeter and thus illegal according to bumper rule L:

Does the bumper perimeter have to be rectangular? We are planning on running the bumper into our bot six inches.

Just for example... what if you had an L shaped robot?

[NickE]

Where's the cRIO?

Originally Posted by falconmaster

Does the bumper perimeter have to be rectangular?

Originally Posted by 2009 FRC Manual Section 8.2

BUMPER PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT (without the BUMPERS or Trailer Hitch attached) that are within the BUMPER ZONE. To determine the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon.

i.e. The bumper perimeter must be a convex polygon.

[falconmaster]

Originally Posted by NickE

Where do the cRio and Spikes go? i.e. The bumper perimeter must be a convex polygon.

That is interesting, where does it say that it must be convex?

That would settle the dispute......

Thanks for helping to vet us. We don't want to caught at a regional with a violation.

[NickE]

Originally Posted by falconmaster

That is interesting, where does it say that it must be convex?

It never explicitly says that it must be convex, but wrapping a string around a concave polygon will result with the string not following the entire perimeter of the polygon. If you wrap a string around this robot in the bumper zone, it will form a convex rectangle.

[falconmaster]

definition per rules
To determine the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon.

We would have our string cross the opening of our bot. It does not say it has to make contact with the bumper zone everywhere. That is an assumption. Our polygon would be a rectangle, never the less we will cover the angles in from the corner with 6 inches of bumper. We think we are ok......I hope

[NickE]

Originally Posted by falconmaster

We would have our string cross the opening of our bot. It does not say it has to make contact with the bumper zone everywhere. That is an assumption. Our polygon would be a rectangle, never the less we will cover the angles in from the corner with 6 inches of bumper. We think we are ok......I hope

Would the bumpers be straight (parallel with back of bot) or angled (parallel with angled front sides of bot)?

[AdamHeard]

Originally Posted by falconmaster

definition per rules
To determine the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon.

We would have our string cross the opening of our bot. It does not say it has to make contact with the bumper zone everywhere. That is an assumption. Our polygon would be a rectangle, never the less we will cover the angles in from the corner with 6 inches of bumper. We think we are ok......I hope

I believe the intent is that bumpers must be on the bumper perimeter. You're taking a risky move, and should probably Q&A it.

[eschanz]

Originally Posted by thehurd03

They don't have to, The rules say you have to cover 75% (I think) of the perimeter of your robot.

but i heard that bumpers have to cover corners.

[GaryVoshol]

Good news or bad news?

http://forums.usfirst.org/showthread...4097#post24097

Confirms that both sides of all corners must be protected by BUMPERS.

Doesn't explain how a BUMPER could be legally attached inside the BUMPER PERIMETER.