I am using the following DC geared motor which is equipped with quadrature encoders and i want to find or measure the backlash in the gears.
My approach would be to use a pen to make a vertical mark on the black rubber wheel rim, and manually move the wheel and put a protractor next to it to measure the angle. But that method is not very scientific, i suppose? And also, not quite exact.
I'm wondering what are other ways to get a better and more accurate measurement? Could i use an Arduino sketch to move the motor and somehow use the readings from the encoder to get a more accurate estimate of the backlash? I'm not sure what kind of contraption i would need to attach to the motor though.
Most encoder motors have the encoder on the armature, so one idea would be to have an addition encoder mounted on the gear output shaft.
Run both encoders into separate count program, run the motor one direction ( further than the expected backlash), zero both counts, run motor in the other direction ( further than expected backlash) and read out the result as a difference.
Compare angle or whatever to total count per revolution in the specs.
Note:- I'd tend to load the output during the test so it does not overrun.
Zero the encoder count, clamp the output shaft so it cannot rotate, run the motor forward just long enough to see the encoder count (less than 1 second), repeat for reverse, subtract one count from the other.
JCA34F:
Zero the encoder count, clamp the output shaft so it cannot rotate, run the motor forward just long enough to see the encoder count (less than 1 second), repeat for reverse, subtract one count from the other.
Encoder is mounted on the armature shaft if I am not mistaken, so no backlash there.
JCA34F:
Correct, backlash is in the gear train between motor and output shaft, so, if output shaft can't move and motor still moves, that is backlash.
Difficult to hold an output shaft reliably which is geared down.
Woulds need to be locked in position and possibly damage the armature winding or brush gear.
Note that the brush gear in some of these motors is a simple spring leaf.
