6. Interpolation Functions
6.5 R-specified Circular Interpolation
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6.5 R-specified Circular Interpolation; G02, G03
Function and purpose
Along with the conventional circular interpolation commands based on the arc center coordinate (I,
J, K) designation, these commands can also be issued by directly designating the arc radius R.
Command format
G02 (G03) X__ Y__ R__ F__ ;
X
: X axis end point coordinate
Y
: Y axis end point coordinate
R
: Arc radius
F :
Feedrate
The arc radius is commanded with an input setting unit. Caution is required for the arc command of
an axis for which the input command value differs. Command with a decimal point to avoid
confusion.
Detailed description
The arc center is on the bisector line which is perpendicular to the line connecting the start and end
points of the arc. The point, where the arc with the specified radius whose start point is the center
intersects the perpendicular bisector line, serves as the center coordinates of the arc command.
If the R sign of the commanded program is plus, the arc is smaller than a semisphere; if it is minus,
the arc is larger than a semisphere.
Center point
Arc path when
R sign is minus
L
r
Arc path when
R sign is plus
End point
Center point
01
Start point
02
Center
point
The following condition must be met with an R-specified arc interpolation command:
L/(2xr)
≤
1 An error will occur when L/2 - r > (parameter : #1084 RadErr)
Where L is the line from the start point to end point.
When the R specification and I, J, K specification are contained in the same block, the R
specification has priority in processing.
When the R specification and I, J, K specification are contained in the same block, the R
specification has priority in processing.
The plane selection is the same as for the I, J, K-specified arc command.