Thread: Inertia issues
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Unread 18-07-2012, 16:00
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Re: Inertia issues

Quote:
Originally Posted by Levansic View Post
What do you mean by reflected inertia?

-- Len
http://www.diequa.com/download/articles/inertia.pdf

I didn't know what it was either, but I learned a lot about it there. I still don't know enough to answer your question, but maybe someone else here can. I've never done one of these calculations with one of our robots before, but after reading this I may start for chain/cable driven mechanisms that require precise motor control. So I guess it wasn't the programmers' fault all along?

Layman's terms/"TL;DR": the amount of inertia the motor shaft sees transmitted from the load. Modeled ideally by Load Moment of Inertia/[Mechanical Advantage]^2. Useful when precise motor control (i.e. speed or position control) is necessary and the motor is not rigidly coupled to its load. A large difference between the reflected inertia and the motor shaft inertia can explain why some arms or other mechanisms always seem to oscillate rather than behave as controlled. Not exactly Layman's terms, but I think most people on ChiefDelphi would understand most of that.
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Last edited by KrazyCarl92 : 18-07-2012 at 16:11. Reason: Added summary of Reflected Inertia