Comment by 01HNNWZ0MV43FF
17 days ago
Nice that the servo tells you the position. The only time I used a servo it was a cheap 3-wire one, and it didn't tell me the position. So even though it was "closed-loop" internally, it was open-loop from the perspective of my code. Still mad about that...
R/C servo? If so that's not surprising: they're designed for use in radio-controlled vehicles where the main feedback to the operator is the vehicle's motion.
When I was about 13 I took apart a broken servo from a hobby RC car I had. What a revelation to me. The circuit board was pretty mysterious to me, but I noticed the encoder (didn't know what it was called then) on the output shaft, and immediately realized its purpose. It looked to me a bit like a volume knob. I wondered why the servo motor didn't keep turning, but I realized this thing must be telling the motor "a little more" or "a little less", and it would have to keep making small oscillations back and forth to compensate for external forces, etc, which explained all the twitching noises it made. It was a great discovery at that age.
It's amazing how many parts they fit into such a tiny space, isn't it? Those things are little marvels.
It's a potentiometer most of the time, BTW. Encoders are on the spendy "digital servos"
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