What VEX-legal weights can I use to weigh down my robot? I already know that brains, batteries, and air tanks (for pneumatics) are heavy, but are there other things that are heavy or are designed to make robots heavier?
Steel C Channels instead of aluminum. steel is much heavier than aluminum.
Out of curiosity, may I ask why you are trying to increase the weight of your robot?
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You usally don’t want to make your robot heavier, that will decrease your aceleration. If you really want to, try building the frame out of steel and add the 5x steel C-Channles or support. That will make your robot stronger and… heavier.
Seriously though, why do you want to make your robot heavier?
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Im not sure why you would want a heavier robot, but if anything, just use more metel than you need for crossbracing/structure and taking the heavier options of things like instead of using nylon screws, ue metal. Maybe even use steel structure. Not sure why you want a heavier robot so if you could, please clarify the reasons.
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I’ll bet it has a too high and off center center of mass and the robot falls over.
It’s easier ejuneering to add weight than doing some decent engineering to make the robot stable.
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If that’s the case, then I would recommend they still make sure things are properly braced and then also place everything as low as possible. Motors, battery, air tanks. Easier said than done sometimes of course.
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Is a 4 motor 450 rpm drive reccomended - VEX V5 General Discussion - VEX Forum:
I feel like my 6-omniwheel, 6-motor robot should be about 60 in/sec. My robot is about 42 in/sec. It’s only about 4 kg, or 8.8 lbs, making it both light and slow. I thought I might as well take advantage of the torque and add weights to make it move less when rammed and make the robot more stable.
Now that you mention it, I’m also concerned about robot strength; the C-channels are sometimes bent so I have to bend them back straight.
May I ask how you know it is only 42 in/s? That’s a lot of speed lost. Have you checked for friction issues? Also 8.8 lbs is really light for a VEX robot (I think the electronics, etc. are 6 pounds alone). You should be able to go up to like 15 pounds just fine with your drive speed.
Honestly as for having it move less, just put traction wheels to stop being pushed around, more weigh will only harm you imo.
If you just want to make your robot heavier go for it, but I’m sure we’d be happy to help if you had specific goals like you really just want your robot stronger, harder to push, and faster.
I would recommend checking this out though: Designing Another Quality Drive
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It’s not speed lost—the drivetrain is direct drive 200rpm. I didn’t time the bot; I just calculated from wheel diameter and rpm. There might be friction issues.
6 motors: 1.2 kg
6 wheels: 0.8 kg
Battery: 0.3 kg
Brain: 0.4 kg
Drivetrain (6 motors, 6 wheels) & Brain & Battery: 3 kg
1-motor Conveyor mechanism: 0.6 kg
1-motor Mobile goal clincher/clamp: 0.4
The bot is already pushing the 18" size limit (except in height) so my team didn’t use gears. (It’s my first year and I built the drivetrain before I discovered Vex Forum)
I don’t have traction wheels; the only 4" wheels I have are standard and omni. The 4" standard wheels are smaller than my 4" omni-wheels, so I’ll need extra weight anyways to get the standard wheels to grip.
However, I have four 3.25" traction wheels and four 3.25" omni-wheels which are all the same size (unlike the 4" wheel mentioned above). (sigh) I guess I’m rebuilding. (btw I don’t know how to use CAD)
Ok, I see. Actually if you have the time using the 3.25 inch wheels and going for a faster drive ratio like 400 RPM (2:3) is a great idea. That way teams would have to chase you down to push you around.
On a side note there are tons of CAD tutorials, even ones just for VEX on YT. I don’t CAD either and while it would have saved me a lot of time here we are and I am technically doing just fine.
Let us know if you need any more help and sorry if I have seemed unhelpful, I just thought that you would have wasted your time going for heavier stuff alone instead of exploring other options.
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I can’t cut metal or get extra parts (gears, gear inserts, blue cartridges) at home during Winter Break 
so if I’m gonna make a geared drivetrain I’ll have to do it during team meetings.
(I’ve tried getting student access to Inventor and Onshape but both don’t work (I’m in middle school))
(Graph paper ig)
Thanks for the help everyone
I think Onshape is free to make an account and start cadding
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