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Torque Required to turn a wheel

  1. Jul 22, 2016 #1

    I am trying to figure out how much weight a particular motor/wheel setup can handle.

    I have an electric motor that puts out 6000ft*lb of torque, and is driving 44" wheels and needs to reach a maximum of 2RPM. Acceleration doesn't really matter so long as the wheels are able to get up to speed in a reasonable amount of time.

    How much weight am I capable of handling on this setup?
  2. jcsd
  3. Jul 22, 2016 #2


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    You limitations will be in the inertial of whatever wheel you are accelerating, and the load ratings for the bearings supporting the wheel. 6000 ft-lb of torque sounds like a lot, are you sure you're right on your number there?
  4. Jul 22, 2016 #3

    jack action

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    Rolling Resistance + ma = Driving Force​
    [tex]R_r W + \lambda W \frac{a}{g} \le \frac{T}{r}[/tex]
    [tex]W \le \frac{T}{\left(R_r +\lambda\ ^a/_g \right) r}[/tex]
    In any cases, the Driving Force will not exceed the available friction force (##\mu W##), thus:
    [tex]W \le \frac{\mu W}{R_r +\lambda \ ^a/_g}[/tex]
    [tex]R_r +\lambda \ ^a/_g \le \mu[/tex]

    Where ##\mu## is the tire-road friction coefficient.

    EDIT: Added mass factor.
  5. Jul 22, 2016 #4
    Yeah it should be. The mass value I'm hoping to get is somewhere around 100,000 lbs
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