Measurement plane guide lines for the Mentor Visual iQ+ VideoProbe 

In this article:

• Measurement plane guide lines in the Mentor Visual iQ+ VideoProbe are visual reference lines in the point cloud that project cursor positions onto surfaces for more accurate in‑plane measurements.
• The article explains when to use guide lines, including rounded edges, gaps, edge radii, and turbine components where standard point‑to‑line measurements can be misleading.
• It outlines best practices to improve measurement accuracy, such as probe orientation, cursor placement, EVA considerations, and limitations when 3D data is incomplete.

What are the measurement plane guide lines for the Mentor Visual iQ+ VideoProbe?

Guide Lines are shown in the point cloud views when using a Measurement Plane with Length, Point to Line, Multi Segment, or Area. They are shown as black lines that are perpendicular to the Measurement Plane and extend from the cursor locations on the Measurement Plane to surface points straight above or below the cursor locations. Spheres are shown where Guide Lines intersect the surface.

Example Applications:

• Edge damage on rounded turbine blade or vane edges
• Turbine vane platform to shroud gaps
• Edge radius estimates
• Gap width
• Any in-plane dimensions between points not on the same plane

Best Practices to Improve Measurement Accuracy:

• Adjust the cursor positions until the Guide Lines and surface spheres appear in the point cloud view at the desired locations.
• Use when measuring on rounded edges and an in-plane measurement like that obtained using an optical comparator is desired.The conventional Point to Line measurement of a rounded leading edge indication in the lower left image is on a diagonal and therefore gives a larger result than would be obtained using an optical comparator.The same indication is measured in the top left image using a Measurement Plane with Guide Lines to remove the angle.
• Ensure that the rounded edge is angled toward the probe tip and fully visible rather than angled away from the tip.
• Cannot be used when the 3D data does not extend all the way to the edge of the surface.
• Should be used to guide cursor positioning on rounded edges oriented toward the probe tip, especially when the EVA exceeds about 15°. The rounded edge is off the measurement plane, so unless the EVA is low, the cursors cannot be placed properly using only the 2D image.