G02 or G03 is used to designate the direction of the arc rotation.
The arc plane is designated by G17, G18 or G19.
The arc center is on the bisector which orthogo nally intersects the segment connecting the start
and end points, and the point of intersection with the circle, whose radius has been designated with
the start point serving as the center, is the center coordinate of the arc command.
When the sign of the value of R in the command program is positive, the command will be for an
arc of 180° or less; when it is negative, it will be for an arc exceeding 180 ° .