Servo Feedback Hack
I'm sure this has been done before, but I finally got around to trying this idea, four years after I mentioned it: http://forums.parallax.com/showthread.php/84991-Propeller-Application-Proportional-feedback-from-a-Standard-Hobby-Servo-(Upda?p=1028847&viewfull=1#post1028847
Mr. Beau's clever approach (in that thread) is far more sophisticated than my quick & dirty hack. But I was pleasantly surprised at my results for an hour of work.
Basically I added a connection from the servo's center pot wiper to an ADC so the controller can read the position. I did some servo pulsewidth vs ADC tests to make a simple linear (y=mx+b) correlation between the two. Decent results, easily improved by mapping.
As is often the case, a solution in search of the right problem. But fun.
Duane or Martin_H may well have a whole Prop-based robot arm like this with sigma delta converters before I get to play with it again.
Mr. Beau's clever approach (in that thread) is far more sophisticated than my quick & dirty hack. But I was pleasantly surprised at my results for an hour of work.
Basically I added a connection from the servo's center pot wiper to an ADC so the controller can read the position. I did some servo pulsewidth vs ADC tests to make a simple linear (y=mx+b) correlation between the two. Decent results, easily improved by mapping.
As is often the case, a solution in search of the right problem. But fun.
Duane or Martin_H may well have a whole Prop-based robot arm like this with sigma delta converters before I get to play with it again.
Comments
https://learn.adafruit.com/analog-feedback-servos
So she copied me!
Thanks, will digest that.