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View Full Version : Weight? Estmate weight?


Arkorobotics
23-01-2007, 00:20
Jenny Crage for robots anyone? I know it's a bit early to ask, but who here is feeling they are headed down that over weight route? Or are you carefully planning out everything? So far our bot is 70 lbs underweight, hopefully that stays around there, and all we will need to worry about is buying chunks of lead. :D

dtengineering
23-01-2007, 01:49
So far our bot is 70 lbs underweight, hopefully that stays around there, and all we will need to worry about is buying chunks of lead. :D

Yeah... ours is about there too... but we've still got to add the motors, electronics, gearboxes, wheels, chassis, lift, arm, ramp, flag holder...

Nah. We're doing okay. After having to shave twenty pounds in the last week of build two years ago we try to stay on top of things. Just everyone remember to leave a pound or two for repairs at regionals. We started GTR at 118.5 and entered the playoffs at 120.0 last year after some mid-Friday repairs.

Jason

pyroslev
23-01-2007, 08:57
Weight seems to be an enemy more so due to the class system.

I had the nice notion this year of planning weight. (Keyword is had...)

We weighed all the parts, did some serious guestimation on some others. They wrote it all down and I started putting it in an Excel Spreadsheet in Openoffice. The idea was to drag and drop parts into a list and have a reasonable weight window for the robot.

I was down to the Electronics when something happened and I lost two hours of data entry. I have not had time to sit down and put it back into Excel but that is probably something I'll do tonight.

Brian Mocci
23-01-2007, 10:28
We've been planning on a 5foot frame, so 110 pound limit. Finished aluminum base weighs about 35-37 pounds with transmissions in. Add chain and wheels and we are at about 42lbs. This year we are making sure our arm team has enough to play with =P

MrForbes
23-01-2007, 10:36
We're looking at close to 60 lbs for chassis/drivetrain, not including electronics or pneumatics.....leaving the arm team and ramp team very little to play with on a 110 lb robot!

which is a good thing if you look at it from the CG perspective.

Rob Colatutto
23-01-2007, 11:20
We did a "full" CAD model this year for our robot, and according to the computer it weighs 94.4 pounds without electronics, chain, and fasteners. (hence the "full") But this is also coming from the computer that calculated our IFI wheels at 0.79 pounds each... so we'll see how it turns out. A word to the wise...when your doing your computer model... just keep in mind that fasteners can add a significant amount of weight.

A quick on CG though, you want to make sure you keep it lower than the distance between the center of your frame and the front or back drive wheels. This is usually somewhere around 10-15 inches depending on your wheel selection. If not...your robot may have some interesting driving characteristics...

65_Xero_Huskie
23-01-2007, 11:56
Well, right now our robot is only...maybe 10lbs?
----
Maybe we will gain more weight when we add more than just the wheels and control board.:p

I expect us to not be light this year (as in every other year before). I dont see the point in a light robot.

Bochek
24-01-2007, 21:10
our chassis, electronics. air compressor, 4 victors, 4 spikes, all the proper wireing,

Full drving robot as seen here: www.mmrambotics.ca

comes in at a smidge under 50 lbs without the battery.

- Bochek

Beth Sweet
24-01-2007, 21:25
Let me put it this way. I think putting me on the field would weigh less than the robot we're planning. Can we just ditch a battery or a motor? ;)

Cody Carey
24-01-2007, 21:28
We made a custom chassis this year, and when we weighed it, it came to about 42lbs with electronics.

Dan Petrovic
24-01-2007, 22:13
We have an estimated weight of 98 pounds and I believe we're at 30-40... or something. That's just the chassis.

I think we're in pretty good shape.

AustinSchuh
24-01-2007, 23:04
After finally inputing the correct weight of the CIMs and other motors into our model (Which caused a scare one night when I realized that the weight of the motors were ~3lbs total), we are at 103 lbs without ~4 lbs of chain. I feel much better about the robot's weight this year than last year, where we had to remove 10 lbs of weight on the Thursday of the competition. This should be the first year in my 4 years of FIRST where we add extra weight to the robot instead of frantically take it off.

Nick 1523
27-01-2007, 20:32
We've weighed all of the stock parts, frame, and used inventor to estimate weight. We're planning on using the smaller heavier config and weight is gonna be close but I think we'll make it. There's always the hole saw :eek:! But i agree i would much rather add lead weights than end up making swiss cheese out of our bot.:D

Koko Ed
27-01-2007, 20:35
We have a practically fully built robot and it's 82 pounds. We'll see how much weight adding a ramp will cause her weight to "ramp up" (couldn't resist. Sorry).

deshirider430
27-01-2007, 22:40
can we claim to have ours weighed according to the moons gravitational pull? it would really help us alot

Priyadarshy
27-01-2007, 22:47
too bad our school is on earth

Syncopation
27-01-2007, 22:49
I see a huge number of teams struggling to meet the weight limit (more so than usual... :rolleyes: ). I can't foresee it being really easy to build a 100 lb, 6 ft. 'bot without sacrificing something.

EricH
29-01-2007, 01:57
Last estimate, a hair over 95 pounds. And about half to 3/4 of that is actual weight.

Barry Bonzack
29-01-2007, 11:02
We plan to have both an arm that can reach all three levels and a ramp that can lift 2 robots.... I'm betting week 5 will tell us to sacrifice something.

Justin M.
29-01-2007, 14:12
The bare chassis is about 20lbs. With motors, electronics, chain, and more bolts I'd say around 50lbs. for the whole moving chassis....this is gonna be tight.

RoboDriver1718
29-01-2007, 17:25
Yeah, we have the control board being built right now, but the chassis alone is just 18 pounds with the wheels(no motors or chains) but were are shootin for the 4-foot 120 pound bot so things are looking good.:cool:

EOC
29-01-2007, 17:34
Our bot wieghed in today at 113 pounds. In theory everything is on it. We will see.