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Greater than 360 Servo (not continuous)

 

There was a question in the Shout Box earlier from noise0. He wants to turn a turret with srf08 sensor and be able to rotate at least 360 degrees. But it does not have to be continuous. He can go from 0 to 360 and then reverse direction back to 360.

There were a lot of ideas including a super modified servo (http://www.01mech.com/supermodified), stepper motor, or motor encoders.

I had a different, and I think simple solution. Just use a normal servo with 180 degree (or slightly less) freedom, and gear it up so the output of the turret gets greater than 360 degree freedom. Pick two gears with maybe a 3 to 1 ratio. The larger gear is attached where the servo horn usually goes. The smaller gear drives the turret.

Now you get decent positioning, more than 360 degrees of freedom and it is easy and cheap.

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360 degree servo but still a regular servo. This is not a continous revolution servo, it is a regular one that just happens to go 360 degrees. Less than 20 bucks, done.

http://www.acroname.com/robotics/parts/R298-1T-SERVO.html

Even better! Nice find, CtC.

your idea is perfect, thankyou

Cool! Post back if you can with your implementation.

Good luck!

I heard there are servo motors made for sailing boat models, which rotate 3-5 circles, so he could use that. But I never actualy saw a servo like that, so I don't exactly know how it works, but it probably is just a normal servo with gears like you said.

I think sailing servos are big, massive things. If he's just trying to turn a model turret with an srf08, he doesn't need all that torque (or cost).

used to act as tiny winches or for the tiller/rudder

example http://www.servocity.com/html/s5801_sail_winch.html

Dang: $150  !?!?!