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Old Mar 25, 2012, 07:48 PM
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Arx
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Arx
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Joined Mar 2012
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A transfer function can only be used to completely characterize a linear system, which this isn't.

There are limits intentonally imposed in the firmware for ramp-up speeds, etc, which can vary in implementation drastically. Your testing is likely to bump into these limits, and depending what you have for a load, will give you results completely independent of what matters.

To use an extreme example, If you were to test with a completely unloaded motor, with an ESC with no accel/decel limiting, it would respond "extremely well" on your test. Yet the same setup, with a heavier load, would probably just stop and vibrate, making some high pitched squeeling noises.

Regarding that test video with the motors bouncing around, I gotta agree with timecop on this one.. You need to try and understand what's going on there. That's a lot more revealing than what your "transfer function" will be.

Kudos for trying to put some engineering into it, but be careful what you present as fact, based on a single, fairly limited test.
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