@24523B and I will be attempting to build an advanced robot in 2 weeks before states. Anybody have any tips? Pictures below: 
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Try converting your drive to a 6-motor drive. If needed you could use a PTO. Put a high strength or c-channel under the bot where the mogo would connect the robot because you don’t want it to drag against the ground. Fix your bracing, and add a c-channel against your bars. Your drive may be a little short, but I really wouldn’t see that as a problem. change the drive channels with c-channel and brace it. you may have to remove that back L-channel because it most likely wouldn’t allow for the mogo to be clamped. try using different shaft collars because they could fall off. You can also learn how to screw joints, where there would be a good amount of friction loss.
These are basic improvements, they can always be worked on later.
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Why are the wheels so close together? This would make the bot very tippy. Do you have smaller wheels?
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mumbles in build quality
(btw Ryan Liao’s YouTube channel and 9MotorGang’s Youtube channel have videos about build quality)
From what I can see… hook + ladybrown. The standard design for a decent robot (half-meta?). (I’m kinda making fun of it because I’ve recently had urges to build a High Stakes clawbot.) Is the drivetrain 200 RPM 72 tooth to 48 tooth (ending up as 300 RPM)? Have you checked to see if rings can travel unobstructed through an imaginary intake? (And, if the intake is hook, the C-channels are probably sticking out too much in the back, going past the tip of a (securely clamped) mobile goal.)
For the mobile goal clamp, a design I am interested in is KUdos’s clamp on Pits and Parts. There are two other designs I have in mind:
- Lever: just pneumatics pushing/pulling on a rotating piece of metal.
- Locking mechanism: where the motor/air cylinder can simply move as normal but, in doing that, makes a pivot bend back on itself, making it impossible to steal the mobile goal (without breaking the mechanism). I believe that if a motor is to be used on a clamp, it should be a locking clamp. (Is it possible to use a 5.5 W motor on the clamp?)
@99976D covered all of the basic stuff I can notice. One thing I’d like to say though: a good PTO is not going to be built in 2 weeks.
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Ok, that’s a lot of info. Thanks!
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Pretty sure it’s 60:36 for a speed of 333, you can tell from the size and color (48 and 72 only come in red, 60 and 36 come in green and red)
Otherwise this is a pretty good start, but I think the drivebase may be a little too short and too wide. Also I would switch to full c-channels for the drive, since rails tend to bend a lot more easily.
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one tip is to not use steel for your structure, it is honestly kinda outdated. Most people now only use aluminum. Also don’t use 2x2 L channels for your triangle bracing.
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Do it do it do it
Anyway, it is definitely possible to rebuild in 2 weeks. My team rebuilt 3 weeks before states, and we had a functional ring mech and wall stake. However, this was only because of our planning. I highly recommend making a cad of your entire robot if you haven’t already, and protobot or onshape are very easy to use (there are countless topics about cad softwares on the forum). Additionally, for the build that’s in the picture, why are you using rails (correct me if that isn’t their actual name) on your drivetrain? While I’ve never used them, I would imagine they would be weaker than c-channels. Additionally, are you using flat bearings on your drivetrain? VEXForum won’t let me zoom in on the picture but it appears that you aren’t. If you add some, you can reduce friction by a large margin and increase your speed. Also, don’t use rubber shaft collars on your drivetrain (apologies if that’s not what you’re using, I cant zoom in), I tried that in Spin Up and have of my drivetrain fell off in a single match (yes, that was my team’s first year). Good luck for states!
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Yea we only used steel for the parts we didn’t have in aluminum.
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Eh no because there are no competitive robotics meetings anymore after we disassembled our robot. So I’m basically just coding on Vex VR and the VEX clawbot (which is, for my purposes, a lift and a drivetrain)
My bad, I’ve actually only ever seen 36 and 60 tooth gears in real life before. (Never seen any of the new wheels in real life before either.)
@76782AHighVoltage Are you going to be using the stack of green 2.75" (I believe) wheels in the background for a floating intake? Based (and good use of materials assuming lack of flex wheels) but you might have problems with low grip. (That being said, I’ve only touched green 2.75" wheels turning white (which I believe is rubber blooming) before.)
Also, the “pivot bend[ing] back on itself” that I mentioned is just an over-center linkage (and the locking clamp is sometimes called an over-center clamp).
BTW, if @pmkv is right, you are running a 44 W ~70 in/sec drivetrain! Please, follow @99976D 's advice and change to 66 W (or change the speed (to ~60 in/sec or lower)).
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I’ve recently had urges to build a High Stakes clawbot.
Honestly do it. I’d recommend checking out Texas R2 championships for inspiration. Look for 3350C, Ctrl Alt Defeat. Literally my favorite bot this year.
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i’ve managed to build a bot in about 2 days, it works really good without polycarb hooks. you can take this off as inspiration and to try and aply to your robot. it is fairly small and can run off of 1 piston for mogo.
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We have aluminum (twenty chars)
We don’t have Flex-wheels tho…
you can always modify the design to compensate for your needs. I only have about 2 flex wheels, and i put them on my conveyer. Use the smaller traction wheels or you can use rubber banded gears where the teeth are covered by rubber bands for an equal amount of grip. It’s the best way.
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Feel free to look through some of these topics listed in the post below.
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You will have to click on the post to see what I linked, it isn’t just the youtube videos.
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