anti-gravity-gas
 

alright, what are all you people injecting into your air tanks to make your robots 130lb? we are bordering on 130lb, and we barely have anything! our arms are fiberglass, our transmissions weigh 2.5lb. Then i see all metal robots with 6 wheels, big huge gear boxes, and 10' long arms. whats the secret?

Re: anti-gravity-gas
 

you just have to know were the weight is going to be and work around it we have put on more stuff this year and our robot is more complex then ever and we are still under weight we have 6 cylnders 6 motors and we ended up wiht like 129.5

Re: anti-gravity-gas
 

you could try helium. hidrogen would be lighter but you risk flamibility

Re: anti-gravity-gas
 

well our personal preference is hydrogen, but sometimes that can get rowdy.....

naa im just kidding. all you need to do is selct materials wisely. EX. if something that you are planning to make of 1/2 lexan can be made with 1/4 aluminum, go for the aluminum. (also see the reference on what is called a mill and thing that goes on mill to make big holes...hey im a programmer, what do you want?)

Re: anti-gravity-gas
 

Maybe your frame is the pest - light and less voluminous metal may help i guess.

Re: anti-gravity-gas
 

Wait, is an aluminum plate lighter than Lexan of the same size and thickness? What's the density of each?

Re: anti-gravity-gas
 

from inventor..

it was just an example.. not an actual scenario. i would use 1/4 aluminum and get it anodized cuz it looks uber-cool

Re: anti-gravity-gas
 

no no no, the trick is a well known trick among veteran teams. Its offical FIRST terminology is "Speed Holes". These are the mysterious large 1 to 2 inch holes you'll see scattered about a robot, usually made while standing next to the scale using a large hole saw. Our old engineer leader used to get a little speed hole happy with the drill, he's no longer allowed near a drill. Heh.

Re: anti-gravity-gas
 

Why not a vacuume?
Just evacuate your entire robot. Its less dense then helium or hydrogen.

Or better yet, why not raise the pressure in the building where the regionals are at. That way, if your frame is sealed, the air in your robot is less dense then the air in the stadium.

When you weigh, be sure to use a dead battery (remember electrons have mass)

If you're really adventurous, you could short the terminals on your battery and boil off some electrolyte.

Also, try to cut some weight out of the RC, works every time.

In addition be sure to sabatoge the scale. When the scale is zeroed, put somthing heavy on it, like a battery. Then the scale is "zeroed" at about 13.5 lbs.

Oh by the way, don't actually do any of this stuff, its not GP :D

Good luck yall!

-Andy

Re: anti-gravity-gas
 

Make sure your code has as many 0's as possible...Everybody knows that 0's are lighter than 1's :yikes:

-Scooter

Re: anti-gravity-gas
 

No, no, no! The weight of binary values goes against intuition here. Since the beginning of computer storage, 1's have been represented by holes in paper tape or punched cards, making them lighter than 0's. This has carried through to electronic memory, where a logical 1 is customarily represented by a higher positive voltage, meaning fewer electrons. :D

Re: anti-gravity-gas
 

Actually, if you did a vaccuum, you wouldn't get the upward force of helium (and other) gases. I can have a balloon filled with helium fly up, but a balloon with nothing at all in it just kinda sits there ;).

Of course, the amount of helium in your average balloon lifts a couple of grams, so you'll need a bit more than would fit on a robot to make any difference...

Re: anti-gravity-gas
 

First, you might change to ANSI 25 instead of 35 if you have chains and you can make the change. Second, watch out for steel. Some applications will require steel, but in most cases, find an alternative - aluminum is the choice of FIRSTers it seems. When you put things on your bot, always ask - can this be thinner or shorter? Chances are, the answer is yes.

Also, get creative! Go on down to Home Depot or Lowes or Menards for you Midwesterners. Look around and see what they have for you to play with. You'll find strong aluminum tubes that are very light and relatively cheap. You'll find things like wire mesh, PVC and wood - all of which can replace aluminum and lexan in certain applications. Just make sure you get the light stuff (i.e. NOT oak). Last year 1020 had two pieces of 30"x50" light weight wood on the bot. It weighed almost nothing and just before weighing in, we hit them with a couple hair dryers to get rid of the moisture ;).

Congrats to all on completing your bot (or sorta completing as is our case) and good luck in competition.

Re: anti-gravity-gas
 

Since the ban on exotic materials has been lifted this year ..Your world is opened up..

We use Unobtainium (tough to find though...)

It has a negative density...(-.0314 g/ml)

Works great to alleviate temporary Mid to late February bloating due to post kickoff stress syndrome.

You will, of course, need a prescription to get it

Re: anti-gravity-gas
 

The thing that weighs down our robot is the pneumatics. Our solution was to just drill holes in the rams and tanks. No actually we drilled holes in anything that didnt hold a lot of weight, and removed some pneumatics fittings (those are actually really heavy). Another thing was this giant chunk of 5/8 inch plexiglass, which we replaced with marine grade plywood.