Form Checks

Circularity*

Circularity is evaluated in cross sections along the normal vector of the nominal feature (circle or cylinder). The tolerance establishes the maximum distance allowable between two concentric circles containing the measurements of that part at the cross section location.

Evaluation Process within Sa:

  1. Cross sections are established along the normal vector of the nominal feature and the data is divided into groups based upon their position along this vector.

  2. A plane is fit to the first point in each cross section group (using the actual feature direction vector) and then the points are projected onto that plane.

  3. The minimum size bounding circles are then established on the plane containing the data while holding a common center point and the distance between these is used to evaluate the cross section.

  4. The check reports the worst of the cross section results.