combined free speed of 3 motors

[James Kuszmaul]

I can see how the concepts of free speed, stall torque, stall current, and free speed current can all apply if you only consider specific voltages for each. However, I can't seem to figure out what the motor velocity or motor torque constants mean in the context of having multiple motors, as you will have multiple voltages (ie, you can change the voltage being applied to each motor independent of the voltage being applied to the other motor). But I went ahead and threw in the numbers for getting a reasonable model of a gearbox with two motors (adding a third would just make equations messier).