I am trying to create a information display using servos and it is VERY important that they are calibrated to the same degree (e.g. if 90-degrees rotation in one servo is the same as 90-degree rotation in the other). I have been using the sg90 and sg92R servos from tower pro and they are not the same, often off by at least 15 degrees. I have changed the wiring to make sure it was a servo issue and not an issue with code - nope: it is the servos. I understand that these hobby servo’s are not known for their…quality…so any suggestion on what to use would be greatly appreciated!
Reqirements:
3v-5v
does not need to move anything heavy (basically a piece of paper)
does not need to be fast
just needs to be accurate
Some nicer servos are programmable with a servo programmer.
Update the code for each servo manually after calibrating by hand. The mapped servo values then have to go with that servo wherever it gets installed.
Use limit switches to determine the end of travel and have a power-up calibration phase. This would likely be the best way for most applications.
Use a separate shaft encoder or a servo with a separate output and calibrate to that (Adafruit sells servos with the extra control output).
Switch to using a stepper motor. The motor coils can be better here but you will still want positive control (limit switches or shaft encoder) if you need to really maintain accuracy.
