end to end servo angle

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smohring
 
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Joined: Thu Feb 27, 2014 7:38 pm

end to end servo angle

Post by smohring »

Hi, when students are shopping for a servo in our interactive art class, they need to know what the total rotation is... how many degrees can it move? Somethines this is clearly listed in the technical details, sometimes in the product description, sometimes we can't find a clear answer anywhere. I assume as a novice builder, this is just my lack of understanding... might someone point me to the way one can learn this point of data about a given server?

thanks!

example. Product ID: 1404

Dimensions: 39.55mm / 1.5" x 39.55mm / 1.5" x 19.5mm / 0.7"
Max Dimensions: 55.36mm / 2.1" x 43.34mm / 1.7" x 19.5mm / 0.7"
Wire length (at least): 13cm / 5.1" long
Torque: 90.26 oz*in / 6.5 kg*cm
Speed: 0.21 sec/60°
Weight: 46 grams
Dual ball bearing
Plastic gearbox
Spline Count: 23

in the text it talks about 180, but I can't find where in the basic description 180 is clearly mentioned
"Note that the default servo pulse widths (usually 1ms to 2ms) may not give you a full 180 degrees of motion. In that case, check if you can set your servo controller to custom pulse lengths and try 0.75ms to 2.25ms. You can try shorter/longer pulses but be aware that if you go too far you could break your servo!"

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adafruit_support_bill
 
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Re: end to end servo angle

Post by adafruit_support_bill »

Unless otherwise specified, RC servos have an approximate 0-180 degree range of motion. The industry standard for many decades was a pulse width of 1ms for 0 degrees and 2ms for 180 degrees. Some of the newer suppliers like to use a somewhat wider range of pulse widths for the same range of motion.

You can expect some variability from model to model and unit to unit. So for critical positioning, we recommend calibrating the servo in the system where it will be used.

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