Worried about weight ?

FIRST General Forum
#21

Weighing the robot:
Two years ago, we bought a veterinary scale - it’s large enough that we can set the entire robot on top of it and get a very accurate weight. It was well worth the investment.

Our Robot Weight: We cam in at just under 90lbs. the other day and likely added about 10 lbs. yesterday. The robot at this point is entirely constructed aside from a few smallish pieces of aluminium that need to be positioned to help guide totes and recycling containers to their ideal location inside the robot… And, we might just add one more manipulator, which we’ll keep under 20 lbs.

We do cut it close every year, and this year doesn’t feel any different than normal.

#22

We weighed our robot today with nearly everything on it and came out to 110 lbs. But that was with the 14 lb battery in it.

#23

This year, we’re looking at about 65 pounds again. We’ll probably add ballast for stability.

#24

We are surprisingly light, most years we ride the 120 line without ballast. We are 77.75" high and weigh ~95 Lbs missing only a banner. We will be adding ballast for sure.

#25

We have an electronic “shipping” scale with sufficient capacity, but as we’re also interested in finding our center of gravity, we purchased four fish weighing scales last year, and made four stands modified from those metal hooks used to deep-fry turkeys. Last year we went mecanum (totally underestimating the importance of defense), and wanted to balance the weight on each wheel. This year, we’ve got an H-drive, and we’ve built it so that we can move the strafe wheel forward or backwards in 1" increments, using the holes in the side rails of the KOP drive chassis. As we now plan to carry up to four totes at a time, then stack two more totes and and RC atop that, we’ll probably try to optimize the strafe wheel location for carrying three totes. Knowing the weight at each corner will not only give us total weight, but also COG.

#26

Always worried, weight and time are two of the biggest factors. :eek:

#27

Yeah, I’m worried about weight.

Doctor says I should lose at least 50 pounds. :o

#28

At last check 125 on a scale that reads 2lbs high.

Diet plan involves swapping cims for mini cims.

#29

I think the last year we were overweight was 2008, and we won’t forget that lesson. We are closer to 60# than to 120# now, with everything but a few sensors and cables attached.

#30

not worried at all…

#31

we are 25 pounds to the good with the robot done we just have to support a structure better wich shoudnt come close to 25 pounds

#32

We weighed in the practice bot, when it had almost everything mechanical on it, but no electronics. It weighed 95bls. Then we weighed in after it was completed, and it weighed 130! D:
Thankfully, with some quick thinking, we weighed it in the next day at 116lbs, without sponsor panels. (We didn’t even have to abandon features or swiss cheese!)

#33

Ah. the good ol’ “Forgot about the battery” 14 lbs.

#34

125 lbs with almost everything on it (-battery)
Time to hit the chop shop

#35

What were your sponsor panels made from that they weigh 14 pounds?

I hope you got lots of $$ if they are such “heavyweight” sponsors :wink:

#36

No size limit means a 26’x6.5’ banner with sponsors on it.

#37

We’re worried about weight. We put up a couple of stacks this weekend and all of that’s well under weight. We’ve known all along that we’d want to add a specialty mechanism or two, so we’ve been fairly weight-conscious about everything. If something will be CNC’ed, we save as many ounces as seems practical. If something will be manual milled, we try to do holes, slots or planing. Not everything got done in its lightest form, but I can’t complain that we have an integrated robot with a 9/10 primary mechanism at the end of Week 5.

The good news is, it looks like our entire specialty mechanism will fit in under the 30lb withholding, so we can keep that back for more tuning and focus on driver practice while we can.

It’s the first time we’ve ever actually worried about weight - the rest of the years we knew where we were but didn’t have to modify anything specifically to get under weight. c.g. isn’t the best, but it hasn’t been an issue yet during practice.

#38

40lbs.?! WOW! I think that is the lightest robot I have seen. Ours is currently at 115lbs.

#39

…or maybe someone is stronger than he thinks he is?

#40

We are a 4-H team we use a scale for weighting hogs and sheep. Very portable and light weight. Call your local 4-H in your area.