
antguru

here is a thought that needs some pruning. I need a linear actuator that has about 10 inches of travel. 256 mm. A 15kg rc servo has enough torque but presents a control issue. I would like to get 1mm resolution. I was thinking about moding a rc servo for continuous rotation and adding a dual photo detector inputs and feed the inputs to the a/d ezb inputs. The detectors would be placed 90 degrees out of phase so the ezb could decode the quadrature and count the linear position. Now the real question. Should I use the servo feedback system somehow? Or should I do the math in the ezb and just alter the servo pwm signal somehow? All idea's are appreciated and if anyone has any scripts that might be used, please post. BTW the rc sites have no solutions that I can find, other than very expensive actuators. Thanks Neil
What you want to do seems like a serious custom job...
I also only had about 3 inches of travel.
A 3D printed (or threaded rod) worm gear assembly is probably a good way to go, instead of encoders you could have end stop limit switches. This is the idea that most 3D printers use on their x and y axis'.
Neil