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Unread 13-11-2013, 20:18
DocMartin DocMartin is offline
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[FTC]: Servo specifications?

We have a scoop in the works made from plexi ( very light) and we tossed a servo on thinking it would be able to raise and dump.

only after we built it and testing did we realize it was too weak!.

is there a way to figure this out using math or specs from the servo's?
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Unread 13-11-2013, 20:39
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Re: [FTC]: Servo specifications?

Quote:
Originally Posted by DocMartin View Post
is there a way to figure this out using math or specs from the servo's?
Yes.

1) Take a simple postal scale and measure the force it takes to lift the scoop at some reasonable distance from the pivot point.

2) Multiply that force by the distance from the pivot to get torque. Use a consistent system of units.

3) Compare that required torque to the torque rating of the servo.

You might find this document helpful:
http://stanford.edu/~sebell/firstphysics.html



Last edited by Ether : 14-11-2013 at 16:57.
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Unread 15-11-2013, 21:18
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Re: [FTC]: Servo specifications?

I dont work for servo city, but they have great info and FTC approved parts on thier website...

Here is the specs on the standard servo:
http://www.servocity.com/html/hs-311_standard.html

You might consider upgrading the servo to a quarter scale servo which is newly legal for 2013-2014 which will give you a significant increase in torque:
http://www.servocity.com/html/hs-755hb_1_4_scale.html

Another option is gearing the servo:
http://www.servocity.com/html/32_pit...rvo_gears.html

Also something that helps using servos are servo blocks that take the sideload off the servo horn (a common breaking point for servos):
http://www.servocity.com/html/standa...rvoblocks.html
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