
PROGRAMMING
B–62094E/04
4. INTERPOLATION FUNCTIONS
41
In the polar coordinate interpolation mode, program commands are
specified with Cartesian coordinates on the polar coordinate interpolation
plane. The axis address for the rotation axis is used as the axis address
for the second axis (virtual axis) in the plane.
The virtual axis is at coordinate 0 immediately after G12.1 is specified.
Polar interpolation is started assuming the angle of 0 for the position of
the tool when G12.1 is specified.
Specify the feedrate as a speed (relative speed between the workpiece and
tool) tangential to the polar coordinate interpolation plane (Cartesian
coordinate system) using F.
G01 Linear interpolation
G02, G03 Circular interpolation
G04 Dwell, Exact stop
G65, G66, G67 Custom macro command
G90, G91 Absolute command, incremental command
G94, G95 Feed per minute, feed per revolution
The addresses for specifying the radius of an arc for circular interpolation
(G02 or G03) in the polar coordinate interpolation plane depend on the
first axis in the plane (linear axis).
⋅ I and J in the Xp–Yp plane when the linear axis is the X–axis or an axis
parallel to the X–axis.
⋅ J and K in the Yp–Zp plane when the linear axis is the Y–axis or an axis
parallel to the Y–axis.
⋅ K and I in the Zp–Xp plane when the linear axis is the Z–axis or an axis
parallel to the Z–axis.
The radius of an arc can be specified also with an R command.
Actual coordinates are displayed. However, the remaining distance to
move in a block is displayed based on the coordinates in the polar
coordinate interpolation plane (Cartesian coordinates).
Before G12.1 is specified, a local coordinate system (or workpiece
coordinate system) where the center of the rotary axis is the origin of the
coordinate system must be set. In the G12.1 mode, the coordinate system
must not be changed (G92 relative coordinate reset etc.).
Tool length offset must be specified in the polar coordinate interpolation
cancel mode before G12.1 is specified. It cannot be
specified in the polar coordinate interpolation mode. Furthermore, no
offset values can be changed in the polar coordinate interpolation mode.
D Distance moved and
feedrate for polar
coordinate interpolation
The unit for coordinates
on the hypothetical axis is
the same as the unit for
the linear axis (mm/inch)
The unit for the feedrate
is mm/min or inch/min
D G codes which can be
specified in the polar
coordinate interpolation
mode
D
D Current position display
in the polar coordinate
interpolation mode
Limitations
D
D Tool length offset
command