Geo correction maps commanded CAD-space motion to corrected actuator-space positions. This mapping applies to KMotionCNC DROs, G-code, and jogging directions, so a commanded move along one CAD axis can require coordinated motion from multiple motor axes.
Understand the Two Coordinate Spaces
CAD space contains the machine coordinates presented to the operator. KMotionCNC DROs, G-code, and jog commands operate in this space. Actuator space contains the corrected KFLOP axis and motor positions. Geo correction transforms between them in a manner comparable to non-linear kinematics.
| Space | What it represents | Where it appears |
|---|---|---|
| CAD space | Commanded machine position and direction | KMotionCNC DROs, G-code, and jogging |
| Actuator space | Mapped positions required to produce corrected tool motion | KMotion Axis Screen |
Predict Jogging and Position Readouts
Geo correction affects jogging. When the operator jogs in the CAD-space X direction, the tool should move in that direction and the DRO should report X motion. The mapping may move multiple motor axes to preserve the commanded tool path; the KMotion Axis Screen shows those adjusted axis or motor positions rather than the uncorrected CAD coordinates.
The correction is computed under Windows a few times per second. Small errors may appear while the machine is moving or reversing direction, but the final position should be exact. Evaluate final settled position separately from transient path behavior.
Interpret the Geo Correction Table
The example defines a table with two rows and two columns, a grid spacing of one unit in each direction, and a table offset of -0.5 in both CAD axes:
2,2
1,1
-0.5,-0.5
0,0,-1,0,0
0,1,0,-1,0
1,0,0,1,0
1,1,1,0,0The offset aligns the CAD-space origin with the table point at row 0, column 0. Here, the four table points form a one-unit square whose CAD origin is at its center. Shifting the origin by -0.5 on each axis places the table reference at the lower-left point. The evidence identifies the remaining records as grid corrections but does not define each correction component; preserve the documented field order rather than inferring unsupported meanings.
Configure and Verify the Mapping
- Determine where the CAD-space origin lies relative to the table point at row 0, column 0, then set the table offset to perform that shift. For the documented centered one-unit square, use
-0.5,-0.5. - Jog separately along each CAD direction. Confirm that the tool follows the requested direction and that the KMotionCNC DRO changes on the commanded CAD axis.
- Compare the KMotion Axis Screen with the DRO. Corrected motor positions may change on multiple axes even when the CAD-space command changes only one coordinate.
- Stop at a table location and allow motion to settle. Verify the final position independently of any small error observed during motion or direction changes.
FAQ
Does geo correction affect jogging in KMotionCNC?
Yes. Jogging occurs in CAD space, and geo correction maps that command into the actuator positions needed to move the tool in the requested direction.
Why do multiple motor axes move during a single-axis jog?
A single CAD-space jog can map to several corrected actuator-space positions. The DRO reports the commanded CAD motion, while the KMotion Axis Screen shows the adjusted motor positions.
What does -0.5,-0.5 mean in the geo correction table?
It is the table offset. In the documented two-by-two table with one-unit grid spacing and a centered CAD origin, it shifts that origin to the lower-left row 0, column 0 table point.