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lnxfergy
06-27-2008, 01:35 PM
Ok, so I've read through the whole manual and taken a look at the different threads about the AX-12s. Here's the question I have: are they truly accurate?

What I mean: is 511/512 exactly centered? Is the position a true linear function, i.e. the angular distance between 1023 and 512 is the same as 0-511? Obviously, I know perfection never happens, but I'm looking for about plus or minus 3 or so degrees.

I'm coming from analog servos (HS-311, 475, etc). I'm looking to replace the pan/tilt servos on Xr-B3, because I have found that:
A) I have to calibrate the center (knew that already)
B) this calibration depends on temperature (also knew that already)
C) the servo position isn't quite linear (i.e. moving the head 90 degrees left isn't the same change as moving 90 degrees right).

What do you guys think, is the AX-12 gonna work for me?

-Fergs

JonHylands
06-27-2008, 09:52 PM
A) You don't have to calibrate the center. They are always the same.
B) Doesn't depend on temperature - but, even if it did, you can ask the servo for its internal temperature
C) Very linear - I won't say its perfect, but its about as close as you can get. You can run two of them face to face synchronously, and they stay pretty much perfectly aligned

lnxfergy
06-27-2008, 10:06 PM
Thanks Jon,

-Fergs