Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: Ecir Hana on November 23, 2009, 07:19:45 PM
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Hello,
if I understand this correctly to move a servo to a certain position one has to drive the signal wire with desired PWM value so long until it finally moves there. Is this correct? How do I know then if the servo is already in the position or if it is just moving there? I mean, a servo is left and I want to turn it right - how to I know that it stopped moving and is on the right hand side?
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Hobby servos don't have feed back so you have to just trust that they will go to where you tell them. There are ways to add position feed back to them though.
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Hi,
[...] drive the signal wire with desired PWM value so long until it finally moves there.
You make it sound really slow.
How do I know then if the servo is already in the position or if it is just moving there?
What's the reason you need to know?
I mean, a servo is left and I want to turn it right - how to I know that it stopped moving and is on the right hand side?
Oh well, either detect position optically or measure the current draw.
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What's the reason you need to know?
I wanted to perform a sequence of action based on the completion of previous steps.
You make it sound really slow.
Ha! Actually, thanks a lot! If the servo doesn't make any noise - it's there! Just wire up some mic to ADC... Or hall sensor for the rotor...
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Ha! Actually, thanks a lot! If the servo doesn't make any noise - it's there! Just wire up some mic to ADC... Or hall sensor for the rotor...
...or a current sensor to the servo!!! ( as stated before)
That would be a better idea as it would be immune to interference. The mic would pic up everything making noise.