UNITs vs Arcs question

UNITs vs Arcs question

In and XY motion system, if you make only linear lines, it does not matter if X and Y UNITS are not the same. But the MOVECIRC and MHELICAL must have the UNITS on X then same as UNITS on Y, otherwise they produce elipses and not circular arcs.

The solution is STEP_RATIO for a stepper axis or ENCODER_RATIO for a servo axis. It's safe to divide down the counts because then it won't lose resolution.
Say UNITS for X is 100 and for Y it is 150. Use the step ratio to force the UNITS to be 150 for both.

STEP_RATIO(100, 150) AXIS(x)
UNITS AXIS(x) = 150
UNITS AXIS(y) = 150

Note that for EtherCAT and RTEX position axes, you must set both STEP_RATIO and ENCODER_RATIO.

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