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Unread 07-02-2007, 11:42
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Kevin Watson Kevin Watson is offline
La Caņada High School
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Re: Distance to travel once targetted?

Quote:
Originally Posted by baclaskya View Post
Thanks Kevin. This looks great. I'd like to try and make similar adjustments to our camera. However, I'm not sure about the terms that you are using and how they apply to control the pwm outputs. Is there a document that describes the function of pwm outputs (ie. gain, pulse width, etc.) and how servo motors respond to them? I'd like to get a better picture of how the gain of 70 and calculated pulse width of 2.389 combine to control the camera tilt to reach 90 degrees. Thanks again.
Heres a quick introduction to servos. The center and gain values are in units of 100 ns, so a gain of 70 means the pulse width will increase (or decrease) by 7.0 us for each count above (or below) 127. The absolute pulse width at 127 is defined by the center value, which is nominally 15000, or 1.5 ms.

-Kevin
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Kevin Watson
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