I was also cadding a 300rpm 4" drive, it spaced apart the gears and wheels with 1/2" spacers, and put a shaft collar on the 36t gear. One thing I recommend for you is to screw joint your wheels and connected gears, you’ll have a lot less slop and friction. You’ll just need to connect the wheels to the gears.
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The thin McMaster Carr’s Spacers works (watch 515r bot explanation)
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Right you are. The remedy is to switch to the newer anti-static version of the 4" omnis, which are ever so slightly smaller than the old 4" omnis and will give you enough clearance for a spacer or shaft collar.
Doing so will also make it possible for you to bolt the 72t gears to the wheels and use long bolts instead of shafts as the axles for the wheels.
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I believe you should use shaft collars. There are also thinner diameter spacers, but they don’t come in standard sizes.
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thise are old omnis and they are actually 4.125in no 4inch so if u use the new antistatics it should work fine
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Just out of curiosity, would a 400 rpm drive work with 4 inch wheels? 2 red cartridge and one 5.5 w motor on each side for referance, 2:1 gear ratio.
That would be 83.8 in/s, which is much faster and weaker then you would want. You want to keep your drivetrain’s max speed between around 55 in/s and 70 in/s for a good mix of torque and speed (obviously dependent on the game and your strategy). You can calculate speed of the drive by multiplying the circumference of the wheel by the wheel rpm and dividing by 60.
Also, I’m assuming you mean green cartridges, which run at 200 rpm (the same as 5.5w motors) instead of the red 100 rpm cartridges.
Yes, I did, sorry.
Are you having a problem creating your own CAD? Just to let you know the wheels are offset by 1 hole to the gears, if that is your problem.
Just want to know, what modeling software is that?
So, I have been wondering, is it better to have a high RPM go into a worm gear to increse torque, or have spur gear increase torque without a worm gear.
We use solid works. 20characters
My team needed a more compact 360 RPM drive that still has 8 wheels so I quickly stirred this up in my head. Would this be a good alternative to the normal 360 RPM drive? I haven’t given this much thought and I don’t know if there is any major flaw that I’m missing. Thanks in advance.
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This design looks super cool! Go for it, just try to put the battery/pneumatic tank(s) as low as possible to lower the center of gravity.
Since the motors (which I’m assuming will be driving those 36t gears) will be mounted up high, you will need to adjust for that in the rest of the robot design.
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You also might have an issue with the driving gears being mounted on the top hole of the channel, I might suggest moving the wheels to the bottom hole of the channel so you can mount the motors in the middle hole
I made this just ignore the direct drive pages bc those are illegal now. It does all rpms and inches per second of wheel types.
https://docs.google.com/spreadsheets/d/1NrqDXP0-8fqYo_nvH43R81sxrbHLrXZg/edit?usp=sharing&ouid=114722734823902388812&rtpof=true&sd=true
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Can you make the permissions so anyone can view it?
Just make everything not driven by a motor screwjoints, because of the amount of friction screwjoints eliminate
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