what would be a good gear ratio for speed for a drive train that uses 2 motors instead of 4
thanks
none
2 motors won’t be enough to survive defense and you’ll struggle with having enough torque to platform. Use 4. 6 is better
yw
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if you put a small metal gear and the biggest gear you can find, with the small gear attached to the motor, you can make your 2 motor drive very fast (200 * 7/1 = 1400 RPM).
this is not a very good idea. first off, you should have at least 4 motors on your drive and 1400 rpm is wayyyy to fast. something like 200rpm is a safe bet
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If you were using four motor drive, you would probably have an around 300 rpm drive with 4" wheels. If you want to get similar torque (for acceleration, an extremely important part of the game), you would need to use 150 rpm, which would be too slow to play this competitive game. If you keep the speed with a two motor drive, you lose a severe amount of acceleration. Either way, you will not be very competitive. That is why @Ethan5956F correctly said that you should not use two motors.
i know that 2 motors is the not ideal amount of motors of drivetrain in vex but i think my school only has like 5 motors that work
4 for a drivetrain would not be a bad investment. You can make do with 1 motor for a lift and pneumatics for everything else
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in that case, you will have to run your drive at 100rpm at the most in my opinion
If you attach the motor to the 12T and not the 84T, you’d only achieve 29 RPM.
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well dang coach said we are not allowed to get pneumatics I guess I just have to wait until next year
You can still use passive mechanisms and be fine. 4m drive 1m lift, everything else passive. It probably won’t win many comps but the experience you can gain from building passive mechs will be useful for when you have more motors
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2m drive really doesn’t cut it this year.
if you only have 5 motors, you can do what @Ethan5956F suggested and go 4m drive, 1m lift, and then a passive method of holding the goals. If you have a bar on the end of your lift that goes under the lip of the goal, you can put standoffs on that bar that will sort of hook onto the underside of the goal rim, allowing you to lift the goals. It’s not great, but it’s probably your best option.
Unless you want to maybe go the route of 4m drive, and have a single motor forklift. with that, you wouldn’t be able to lift goals onto the platform externally, but you could use the forklift to dump multiple goals on top of your robot, and then park with them. Even getting 2 goals is pretty decent to park with.
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I have this on the back lift of my robot and it works very well. It’s very difficult to take the mogo out even if I am using my hands unless I turn off the robot. One improvement to this is to use white spacers instead of a standoff because they seem to get a better grip on the lip of the mogo.