When you execute your measurement routine, the Roughness Scan command (RGHSCN) performs the following steps:
The controller drives the machine and measures point (S) with the support pin.
After the controller measures the point, the support pin is held in contact with the part.
The roughness measuring needle is dropped onto the part, and PC-DMIS performs the roughness scan.
After PC-DMIS successfully measures the roughness scan, the needle lifts and the support pin moves to the retract distance.
PC-DMIS records the 1, D, and S points as follows:
When you create a Roughness scan command, PC-DMIS highlights the Start Point (1) line in the Boundary Points area in the Roughness Scan dialog box. You can click on the CAD to record the start point, or take a hit on the part with the support pin. After PC-DMIS records the start point, it highlights the Direction Point (D) line.
If the vector of the start point matches the vector of the active roughness tip, then PC-DMIS calculates the direction and support points based on the active tip angles, and displays them in the Graphic Display window. If you want to measure the roughness in this direction, you can click the Create button after you ensure that the roughness parameters are properly set. This feature gives you the ability to create a Roughness scan command with one click.
If the vector of the start point does not match, or if you want to measure the roughness in a different direction, then you can click on the CAD or take a hit on the machine to record the direction point.
If the Snap On button is selected in the Roughness Scan dialog box, the direction point snaps to the nearest coordinate axis.
Usually, PC-DMIS calculates the Support Point from the Start Point and direction point. If necessary, you can click on the Support Point (S) line to highlight it, and click on the CAD or take a hit on the machine to record the support point.
To re-teach any of the boundary points, highlight the line and take a hit on the CAD at the desired location.
Click on the value to type the desired value for any of the coordinates.
More:
Creating a Roughness Scan Command