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Unread 30-12-2013, 13:59
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Re: Gearbox friction model

Quote:
Originally Posted by IKE View Post
While I agree that a certain amount of friction there initially, I think that value should go away once it is overcome, much like the delta between static and dynamic coefficients of friction.
I wasn't talking about static friction. Note how I carefully worded it:

Quote:
at very low speeds and output torque there is friction in the drivetrain (due to tension in the chains/belts, misalignment, etc).
Low speeds, not zero speed. The tension in the chain combined with any misalignment can create a non-negligible loss even at very low speeds even if there is no load on the output. This can be modeled with a constant factor. You may also need a speed-dependent factor, as in your post.