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Homework Help: Optimal gear ratio

  1. Apr 6, 2005 #1
    Hi, I am doing a project that involves an electric motor that winches an object upward pulling it by a string, over a given distance and I need help to calculate an optimal gear ratio, if that is possible. This is how far I have got...

    Variables
    torque/rpm
    gear ratio

    Constants
    distance object travels
    mass of object
    motor input

    to make it simple i am only using one gear, the motor shaft

    acceleration of object = (f/m - 9.8)
    velocity of string = RPM x pie x motor shaft diameter

    assuming initial v=0,
    the derivative of (f/m - 9.8)=RPM x Pie x Shaft diameter

    i am trying to find a correlation between the average velocity the object takes to cross a given distance and the shaft diameter (gear ratio), im guessing its a parabola, but how can i do this? plz help thnx
     
  2. jcsd
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