Author Topic: new servo type: non-continuous without mechanical stop  (Read 2494 times)

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Offline AdminTopic starter

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new servo type: non-continuous without mechanical stop
« on: November 25, 2009, 01:41:55 PM »
Futaba has released an interesting new type of servo.

Its non-continuous, and you can't modify it to rotate continuously.

However, you can manually rotate it continuously forever - making you think it was continuous but not really. It has no mechanical stop, yet still acts like it does when you power it up.

I've only played around with it a little, but I see this as a good thing as the mechanical stops on my Hitec servos keep breaking. Replacement case sets are like $8 . . .

This is the one I have:
http://www.servocity.com/html/s3156_servo.html

Offline waltr

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Re: new servo type: non-continuous without mechanical stop
« Reply #1 on: November 25, 2009, 01:56:19 PM »
A servo with a mechanical stop acts the same way. It's the position of the wiper on the POT verse the width of the pulse (analog type) that determines where the servo stops. You could remove just the stop in a standard servo and it would not continuously rotate. You also must disconnect the pot and insert a fixed value resistor.

Offline SmAsH

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Re: new servo type: non-continuous without mechanical stop
« Reply #2 on: November 25, 2009, 01:58:57 PM »
So, does it still use a pot or what?
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Offline waltr

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Re: new servo type: non-continuous without mechanical stop
« Reply #3 on: November 25, 2009, 03:42:58 PM »
It may not since there are several ways for a circuit to determine the servo's position. One would need to dissect it to find out.

Offline AdminTopic starter

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Re: new servo type: non-continuous without mechanical stop
« Reply #4 on: November 26, 2009, 10:39:02 PM »
Its a digital servo that rotates continuously with power off, so there probably is no pot. I assume it has a built-in quadrature encoder of some type.

Offline SmAsH

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Re: new servo type: non-continuous without mechanical stop
« Reply #5 on: November 27, 2009, 12:45:17 AM »
Ah, i thought that may've been the case...
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Offline Soeren

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Re: new servo type: non-continuous without mechanical stop
« Reply #6 on: November 27, 2009, 08:54:29 PM »
Hi,

Its a digital servo that rotates continuously with power off, so there probably is no pot. I assume it has a built-in quadrature encoder of some type.
The page says: "Potentiometer Drive: Indirect Drive", so perhaps it's just a mechanical coupling with slip when the outside axle is rotated.
Regards,
Sųren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
Engineering is based on numbers - not adjectives

Offline Razor Concepts

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Re: new servo type: non-continuous without mechanical stop
« Reply #7 on: November 29, 2009, 01:07:31 PM »
Hmm... futaba used to make an indirect drive servo, the S148. I actually have a few of them but never opened them up.
S148

 


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