Scenarios¶

Scenarios introduce a set of conventions specific to a given use case, enabling a simple description of the specimen and associated probe and wedge positioning.

Many nondestructive inspection scan plans are referenced to the surface of a specimen. Scenarios corresponding to those use cases link the probe or wedge positioning through (u,v) surface coordinates.

"General Mapping" Scenario¶

Hypothesis:
- This scenario uses \((U,V)\) surface coordinates.
- The probe positioning vs. the related specimen surface is constant for all \((U,V)\) position (skew angle,liftoff, etc.) or automatically compensated (i.e., adaptive acoustic, liftoff compensation, electronic).
- The \(U\) axis is the principal scan axis and is typically collinear with a physical encoder device.
- The \(V\) axis is orthogonal to the \(U\) axis and may be associated to a secondary physical encoder, an electronic scan, or both (for paint brush raster scans).
- The \((0,0)\) position on the surface is arbitrarily defined by the user.


Raster example with the \(U\) and \(V\) axis.

"General Weld" Scenario¶

Hypothesis:
- This scenario uses \((U,V)\) surface coordinates.
- The scenario relates to the inspection of a single straight or curved weld or joint.
- The surface line \((U,0)\) is collinear with the center of said weld or joint.
- The probe positioning vs. the related specimen surface is constant for all \((U,V)\) positions (skew angle,liftoff, etc.) or automatically compensated (i.e., adaptive acoustic, liftoff compensation, electronic).
- For pipe geometry, the orientation of the weld is defined in relation to the pipe axis. With an angle of 0° for an axial weld and 90° for a circumferential one. Any angle in between describes a helix weld.
- Scan patterns can be entirely described on the surface of specimen as a set of orthogonal axes parallel and orthogonal to the weld.


The weld angle is defined in relation to the pipe axis. Axial weld.


The weld angle is defined in relation to the pipe axis. Girth weld.