8.2 Cartesian & Polar Coordinates
With Cartesian Coordinates X, Y, and Z represent distances from part zero (absolute coordinates) or from the current position (relative coordinates).
With polar coordinates, we use an angle and a distance relative to the origin.
The following picture gives a graphical overview.
8.2.1 Use on different planes
8.2.2 Standard syntax
- XY Plane: X is used to identify the radius and Y to identify the angle
- YZ Plane: Y is used to identify the radius and Z to identify the angle
- XZ Plane: X is used to identify the radius and Z to identify the angle
Plane independent syntax
It is also possible to use a plane independent syntax using two special symbols:
@for the radius^for the angle
8.2.3 Examples
8.2.4 Polar Coordinates standard syntax
The following example uses polar coordinates to generate a rotated square and a spiral.
( © 2018 by RosettaCNC Motion ) ( Polar coordinates example: ) G17 G21 G40 G49 G54 G69 G90 G54 F1000 G0 X0 Y0 Z0 (Polar square) G16 ( Enable polar coordinates ) G1 X50 Y90 G91 (Switch to relative) Y90 Y90 Y90 Y90 G90 ( Switch to absolute ) G15 ( Disable polar coordinates ) G0 X0 Y0 Z0 (Polar spiral) G16 ( Enable polar coordinates ) G1 X10 Y90 G91 (Switch to relative) X10 Y90 X10 Y90 X10 Y90 X10 Y90 G90 ( Switch to absolute ) G15 ( Disable polar coordinates ) G0 X0 Y0 Z0 M2
8.2.5 Polar Coordinates complete example
( © 2018 by RosettaCNC Motion ) ( Polar coordinates example: ) G17 G21 G40 G49 G54 G69 G90 G54 F1000 G0 X0 Y0 Z0 (Polar coordinates plane independent style) G17 M98 P1000 G18 M98 P1000 G19 M98 P1000 x100 Y0 Z0 G52 X100 (Polar coordinates Fanuc style) G17 M98 P1001 G18 M98 P1002 G19 M98 P1003 M2 O1000 (Polar square) G1 @50 ^90 G91 (Switch to relative) ^90 ^90 ^90 ^90 G90 (Switch to absolute) G0 X0 Y0 Z0 (Polar spiral) G1 @10 ^90 G91 (Switch to relative) @10 ^90 @10 ^90 @10 ^90 @10 ^90 G90 (Switch to absolute) G0 X0 Y0 Z0 M99 (Polar coordinates Fanuc style XY plane) O1001 (Polar square) G16 ( Enable polar coordinates ) G1 X50 Y90 G91 (Switch to relative) Y90 Y90 Y90 Y90 G90 ( Switch to absolute ) G15 ( Disable polar coordinates ) G0 X0 Y0 Z0 (Polar spiral) G16 ( Enable polar coordinates ) G1 X10 Y90 G91 (Switch to relative) X10 Y90 X10 Y90 X10 Y90 X10 Y90 G90 ( Switch to absolute ) G15 ( Disable polar coordinates ) G0 X0 Y0 Z0 M99 (Polar coordinates Fanuc style XZ plane) O1002 (Polar square) G16 ( Enable polar coordinates ) G1 X50 Z90 G91 (Switch to relative) Z90 Z90 Z90 Z90 G90 ( Switch to absolute ) G15 ( Disable polar coordinates ) G0 X0 Y0 Z0 (Polar spiral) G16 ( Enable polar coordinates ) G1 X10 Z90 G91 (Switch to relative) X10 Z90 X10 Z90 X10 Z90 X10 Z90 G90 ( Switch to absolute ) G15 ( Disable polar coordinates ) G0 X0 Y0 Z0 M99 (Polar coordinates Fanuc style YZ plane) O1003 (Polar square) G16 ( Enable polar coordinates ) G1 Y50 Z90 G91 (Switch to relative) Z90 Z90 Z90 Z90 G90 ( Switch to absolute ) G15 ( Disable polar coordinates ) G0 X0 Y0 Z0 (Polar spiral) G16 ( Enable polar coordinates ) G1 Y10 Z90 G91 (Switch to relative) Y10 Z90 Y10 Z90 Y10 Z90 Y10 Z90 G90 ( Switch to absolute ) G15 ( Disable polar coordinates ) G0 X0 Y0 Z0 M99