Aspects include metrology methods and systems for determining
characteristics of conical shaft portions, such as angle of taper and
crown height. In an example, a metrology system includes a fixture for
supporting a workpiece. The fixture provides for translation in a
longitudinal dimension, and rotation about an axis of symmetry. The
system may include a sensor mounted for scanning lines including sections
of the workpiece as well as control logic for coordinating translation of
the workpiece to provide for an approximately constant ratio of
longitudinal translation and lines scanned during scanning operations.
The system may include image logic for assembling an image from image
data generated during each scanning operation, edge detection logic for
detecting an edge shape in each assembled image, and slope and crown
height calculation logic for calculating a slope and a crown height of
each of the detected edge shapes.