Re: Making Bumper Weight?
 

*looks at pictures of my team's robot*

Nope, definitely not rectangular. The only thing bumpers force in terms of shape is straight segments at least 6in. long for at least 2/3 of a projected external perimeter.

I will agree with you that changing orientations is far more difficult with bumpers.

Re: Making Bumper Weight?
 

Weight issues here (Team 1912) too. I don't get it, we built them to the requirements and used standard 3/4" BC grade ply, standard pool noodles, fabric, very light weight alum angles, small screws, 4-sided (27x37) and came in at 17 lbs. A bunch of 1" lightening holes in the wood, trimming off excess fabric etc. and we are just now getting close to the 15 lb requirement.

Any help would be greatly appreciated!

RikiT-

Re: Making Bumper Weight?
 

You are also now in possession of a pair of non-standard bumpers, according to Q&A. They are not allowing any holes in the backing (other than for mounting hardware). Multiple people have asked.

Maybe just ditching the aluminum angles would work.

Re: Making Bumper Weight?
 

We used 3/4 plywood, medium weight cloth, pool noodles, and stapled on the cloth instead of using angle, 26 x 36 plus noodles in the corners, and they weigh about 12 pounds including a pound of hardware.

Re: Making Bumper Weight?
 

That Q&A question was mine. We had to re-make the boards due to the answer. The wood shop teacher used a plywood that is birch with a maple surface (it think). It was much lighter than the standard stuff you get at the hardware store. I would say that our bumpers probably weigh in at 7-8Lbs. and our frame is 24.5 x 34.5 inches. Sorry I didn't see this earlier or I could ask what exactly it is and where you could get it, but by that time, it will be time to ship.

Re: Making Bumper Weight?
 

Thanks all, we'll remake them with a lower density wood. I'd seen that Q&A response, just forgot to note it and mention that we're now taking a step back...

RikiT-

Re: Making Bumper Weight?
 

I am betting that teams that are overweight are using steel angle instead of aluminum for backing the bumper or have attached mounting brackets to the bumper instead of the robot frame. Mounting brackets are weighed with the robot, not the bumper.

Re: Making Bumper Weight?
 

We've only got minimum length (2/3's) bumpers, and they weigh about 7-8 pounds. So a full set would be about 12 pounds. We're using 1/2" angle aluminum 1/16" thickness top and bottom. 3/4x1" 1/16 thick angle on the 5" vertical pieces, to make sure there is a good surface to take hits. I've seen inadequately protected boards from bumpers that were taken apart after the season, and they ain't pretty.

Re: Making Bumper Weight?
 

We reweighed them with an industrial scale, accurate to .1 lbs, and got 14.6 lbs, so we're pretty sure we're safe. However, we used 1/2"x1/2"x1/16" aluminum angle, and mounted our brackets to the robot.

Re: Making Bumper Weight?
 

Why don't you just take the front bumper off? All its going to do is hinder your arm movement. And besides, nobodys going to ram you in the front, unless they're going in full reverse. (Isn't that illeagal?) This method would reduce your bumper weight by a full 25%. Any reasons not to?

Re: Making Bumper Weight?
 

Or, y'know, unless you'd actually want to run into somebody else.

Re: Making Bumper Weight?
 

Yup. In 2006 we left our front unbumpered so we could pick up balls from the floor. We bent in at least 3 separate guards (each one beefier than its predecessor). Additionally, if our bumper gets in the way of the arm we have really big problems, big as in our arm is no longer attached to the robot. :ahh:

So bumpers are super super good.

Re: Making Bumper Weight?
 

lol.........this is an interesting conversation......

we were never struck with even thinking about issues like this......
we covered our bot with the bare minimum....


we just built a frame strong enough that it dosen't matter if it had bumpers or NOT!

Re: Making Bumper Weight?
 

we just used some plywood and the pool noodles. Our heaviest bumper is like a little more then 3lbs