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countinous Servo Problems 
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Joined: Thu Dec 09, 2010 12:37 pm
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Post countinous Servo Problems
Hi,

I have just found out after buying two hitechnic countinous servos that they don't lock their positions. And the problem is that we are using them as a shoulder for an arm. :( So I was wondering if their was anyone how knew how to mod/fix this either by programming :programmer: , or rebuilding.


Thanks!
SuperCell


Thu Dec 09, 2010 12:46 pm
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Post Re: countinous Servo Problems
Can you please post your code?

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Fri Dec 10, 2010 3:40 pm
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Post Re: countinous Servo Problems
Hi SuperCell,

Continuous Rotation servos cannot lock their position. They function almost exactly like a mini, geared-down motor. They way they work internally is different from a standard servo and they cannot be stopped to hold a position. I believe they basically remove the servo position feedback capability so that the servo is always seeking. And the number passed adjusts the speed. (Speed could also be adjusted on standard servos--changing the delta speed at which it moved from position to position.)

If your standard servos don't have enough range for your needs, I'm almost certain that HiTechnic makes other standard servos with a larger sweep angle. If not HiTechnic, then other servo manufactures definitely do. Check out some servo / robotics parts sites.


Hope that answered your question and helped get you on the right track,

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Bence Feher

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Fri Dec 10, 2010 5:57 pm
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Post Re: countinous Servo Problems
Having gone through the same realization as you have i recommend using encoders on Tetrix Motors in lieu of continuous rotation servos if you must determine angle. In addition, the Tetrix motors are much more powerful and less prone to burn out, as the servos are commonly known to do. Take it from me I would recommend a Tetrix motor over any servo any time. I had the nightmare of having a burnt out servo on a competition bot at World Championships in Atlanta 2 years ago and having to change it while walking from our pits to the competition field in the Georgia Dome. It was quite an experience and a very good learning experience. I only use servos if they are geared up enough and if i do use them I put in code to prevent them from continuously attempting to reach their position.

You are also not allowed to use any other type of servo in FTC and as such you have to make do with what you have.

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Sat Jan 08, 2011 9:13 pm
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