Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: harisankarsa on November 30, 2007, 10:59:55 AM

Title: zero degree in servos...
Post by: harisankarsa on November 30, 2007, 10:59:55 AM
do we hav to turn the pot head so tht its zero rotation perfectly??
I had glued it.then found tht it was not turning due to a small loose connection.
and now it turns at a small rate when connected to the chip with zero degree rotation code...
pls help me fast...
Title: Re: zero degree in servos...
Post by: airman00 on November 30, 2007, 12:24:49 PM
its fine the way you did it


now you'll have to experiment to find how much off you are from the pulse

For example : its supposed to be 150 ( lets say) and now on your servo its 156. Play around to find the pulses for forward , backward , stop ( brake - which is the 0 degree thing you speak of)
                   
Also, may I ask what you are using the servos for?
Title: Re: zero degree in servos...
Post by: bukowski on November 30, 2007, 12:29:41 PM
Think of it as zeroing a scale. If the scale has a wrong reference point for zero, the reading will be that far off. If the servo has a speed of x when it thinks it's zero, whatever input you give it will be input + x. See if you can carefully chisle out the glue, or disconnect the pot entirely and
Quote
take the pot out, and replace the pot with a resistor. 2.2k ohm IIRC

http://www.instructables.com/id/modify-the-hitec-hs-325-servo-for-continuous-rotat/ (http://www.instructables.com/id/modify-the-hitec-hs-325-servo-for-continuous-rotat/)
Title: Re: zero degree in servos...
Post by: bukowski on November 30, 2007, 12:31:31 PM
or you can do it with software, like airman said.  ::)
Im not exactly a great programmer, so I always look for a different solution.