I am trying to prototype a dumper robot, and I am using a gear ratio of a 12T gear, and 84T gear on top, and a 12T gear on top of the 84T gear. I am planning to put 2 motors on each of the 12-tooth gears. However, I have a question about the motors. On one of the 12-tooth gears, if I were to use a turbo motor and a high speed motor, would that not work because the high speed would slow it down? Or would the high speed just provide more torque and power? Please respond back on whether I am able to use two different types of motors (high speed, turbo, regular) on the same axel and how it would affect the robot performance. Thank you!
This is almost definitely a bad idea. You will most likely end up stalling the turbo motors because the arm isn’t moving fast enough, and then once the turbos stall, the speed motors will stall too due to the extra resistance. Your best bet is probably to stick to either all turbo or all speed, and change your external gear ratio (ie 1:7 or 1:5) to get the speed/torque balance you want.
I personally hate doing it, because it makes the motors (generally) difficult to take out and repair, it requires the exact length of axle (which usually culminates in a hacksaw being drawn in our teams) and it requires that the motors be near damn identical (otherwise you can have stalling motors, damaged gears and twisted axles).
Though if I remember, this was a prominent point of debate last year (NBN) while discussing flywheel construction and how to remove friction from your designs.