Re: Robot Weight
 

We're aiming for 120. That way since most teams are around that weight, it'll be easier to balance the bridge. Only thing now is to start drilling holes! :p Actually, we may come in a littl under this year. We'll then need to pack on extra stuff to get to 120!

Re: Robot Weight
 

We're aiming for 120 and on course for 130 :)

Bare frame, pretty much complete with all the mounting brackets for everything, is 27 lbs.

Re: Robot Weight
 

We're at 118 lbs, but a few small components still need to be added. That's too bad, now we'll have to water jet our logo out of some parts of the robot. :rolleyes:

Re: Robot Weight
 

This is a dangerous assumption to make, IMO. Last year, there were 'competitive' robots as light as 90lbs without bumpers and batteries. This year, I'd imagine that there will be a robot or two at each event that are well underweight.

Personally, we're shooting for as low of a weight as is reasonable with the intent of being able to ballast ourselves (method tbd) up to the weight that balances best with our partners, though some testing that teams have done may have proven that this might not be needed.

Re: Robot Weight
 

Our drive alone is 86 lb... I am worried...

Re: Robot Weight
 

That is actually something to be worried about. Ours was ~65 last year, and we had dual layers of T-Slot and tubing, along with 8 idlers and tank treads. This year, we're down to ~50, after beginning the transition to sheet metal construction by water-jetting our side panels out of 3/16th plate. What are you guys doing that requires 86 lbs? Unless its two drive trains for going X and Y, you might want to get out the drill.

Re: Robot Weight
 

I warned everyone about it, but they went with the 14 inch wheels. In order to support those 14 inch wheels, one of our mentors had to make a brace for the sprocket. In order to chain them up, 4 big metal plates are required for the gearboxes. It is slow, sluggish and cumbersome. It was designed to to over the bump, but it flips over.

Re: Robot Weight
 

I second this, our 2012 robot was 78 lbs with the drive-train, and while making weight wasn't all that hard It was very limiting to us and caused a lot of stress. I would try to cut weight wherever you can, learning from last year we managed to got our 2012 robot down to 51 Lbs without any worries about structural strength. If you need more than 30LBS for a frame, you are doing something wrong.

Re: Robot Weight
 

Our drive this year along with our ball sucker and motors are about 48 pounds, and our ball elevator and shooter are about 50, leaving us about 30 pounds for our bridge manipulator. :)

Re: Robot Weight
 

We weighed in at 97.5lbs tonight with mostly everything. We'll probably be at least 110 before everything is on then we'll slap a 9.4lbs steel bellypan on the bottom. :rolleyes: But seriously, I'm pulling for it..

In any case, we'll be 119.9lbs like every year by the time we bag it.

Re: Robot Weight
 

Our team typically doesn't try to make it's robot exactly 120 pounds--it just sometimes ends up that way. However, when the robot it underweight (ie more than a few pounds below 120) we don't go out of our way to add weight.

Remember, although it is true that a heavier robot is harder to push around, a lighter robot has a number of advantages. A lighter robot can accelerate and travel a lot faster, is easier to turn, and is more maneuverable. I've heard that 254 keeps their robot at 90lbs for the extra performance.

Edit: Thats 120, not 1220 lbs. Thanks SuperNerd

Re: Robot Weight
 

Well I hope your robot us under 1220! :p While a light robot has its obvious advantages, heavier robot's advantages are often overlooked. The huge one (pushing power, and harder to push) are not the only advantages of being exactly 120 pounds. A great example is this year. If both robots are 120 pounds (most of them will be), then it'll be much easier to balance on the bridge verses a 120 pound robot and a 90 pound robot (Not saying 254 shouldn't pick us if they're going for 90 pounds. We'd work great together in the elimination rounds! :D)

Re: Robot Weight
 

Our drive train, including electronics and pneumatics, is ~80 lbs. Piling on every component we think we're going to need we get to 107 lbs. Assuming some additional support struts and little wibblybits we haven't made yet and some lexan side panels make up the rest of that weight, we're on target for 120 lbs, maybe a little less -- which we will make up for with ballast.

One goal for us is to keep our CG in the very, very center of the horizontal cross section of the robot and at or below the plane of the frame -- and it looks like that's going to happen!

On a side note, I don't buy that 90 lb robots are inherently faster than 120 lb robots. Depending on the drive train, acceleration can be torque-limited or traction-limited, speed depends on gearing, and turning ability depends on a whole lot more than weight.

Re: Robot Weight
 

Just incase you end up messing yourself up on robot weight, I should point this out now.

Re: Robot Weight
 

lol. As for the math, 48 + 50 = 98. That means we have about 30 pounds for our bridge manipulator, though it won't weigh that much.

I put in the about to make it more accurate. 50 + 48 + 30 ≠ 120, but 50 + 48 + 30 ≈ 120