So I’m going to have nearly the entire weekend to work on my robot, and I have plans to switch our 6m 1:1 200 rpm drivetrain to a stacked 6m 36:84 drivetrain 259 rpm drivetrain. Is it going to be worth it to go this route? I will most pictures either today or tomorrow of our current drivetrain.
Do you have perfect control of your 200 RPM drive? Like no overshot turning or poor straight driving? If you are good with your old drivetrains, then it could be a good idea to speed it up.
If you aren’t, there’s not much to gain from a faster drive.
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Are you sure? I’ve been hearing more and more that a drivetrain around 300 rpm is important
If you’re running 4" wheels, 257 is a more competitive speed but still a little slower than what most teams are running. With 6 motors you definitely have the headroom to go faster. Regardless, 200 is painfully slow so moving up from that speed is a good idea.
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Fast drivetrains are important. Control over robot movement is much more important. If you can traverse the field faster with your 200 RPM drive than you would with 257, there is no reason to change.
However, maybe take a faster bot home over the summer and try to get used to it. Then maybe next year you could build a faster bot.
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I am running 4 inch wheels
I’m sorry I don’t think 259 is nearly fast enough for the current meta, with bowling being so prevalent, being fast is extremely important. We recently rebuilt our robot despite having only 5 days until our signature event (wish me luck) and the main reason for this was speed, we found that against top teams in alliance that we had to face, we were getting punished for our speed. Now we could fix this with weight removal but you will have to speed up your drivetrain to maybe 330 rpm or 360.
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Besides the 36 to 84, are there any other gear ratios you would recommend? We only have 12, 36, 60, and 84 tooth geara
Our team switched from 600 RPM (really fast) with 6 motors, to 450 RPM with the same amount of motors. Our driver likes the 450 RPM drive more as it is well balanced. It is fast enough to compete with other bots, but also easier to control than a 600 RPM bot.
Check out the almighty Catalogue of drive gearings
I have, I can’t find any better ratios with the gears I have
I haven’t used 4" wheels in a long time so I’m not a great resource. Generally, though, you should come up with a range of final drive speeds that you want (in inches/sec), then reverse engineer the final drive rpm you want, and from there you can use the ratio and the gears you have to find something that works.
I’d do 360 on 3.25 (600 Rpm motors spinning 36 tooth gears which drive 60 tooth gears connected to the wheels.)
I don’t have 3.25 inch. Only 4 inch. Is it even possible to do 36/60 on 4 inch?
That’s a tad fast. I’m running 36:72 for a 300 rpm on 4.25s.
Again. 200 RPM works. 257 works too.
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I’m probably just gonna go with the painful rebuild this weekend. We will still have more torque than 99% of robots (only losing to teams that are using 6m direct drive). The extra 60 rpms won’t be game changing but for what little we lose it’s worth it imo.
You could do a 60 tooth idler gear inbetween the 36/60 to basically make it a 36/60/60 but just power the 60 tooth gear.
Would 360 be better than 259? We would lose a ton of torque
We use 6 wheels though so this wouldn’t work
well you could do the idler raised and then you would be able to get 360 on 4 inch
360 on 4 inch is comparable to a rocket ship