Arc Caliper scoring an edge based on its offset from the expected position. l Values in the Constraint Function Editor indicate relative distance in the region of interest where 0.0 is the leftmost position and 1.0 is the right- most position. To set a Position Constraint: 1. In the drop-down list above the Function Editor, select First Edge Pos- ition Constraint or Second Edge Position Constraint. If either edge does not have the Position box checked, it will not be shown in the drop-down list. 2. In the Function Editor, use the mouse to drag handles and set the pos- ition limits. See the following figure.
The physical position in the Function Editor corresponds to the same physical position in the display. Setting the Position Constraint Function Editor Score Threshold The score threshold sets the minimum acceptable score for a valid edge. The caliper will dis- regard edges that obtain a score lower than the Score Threshold. l Caliper constraint scores range from 0 to 1. l If both Position and Magnitude constraints are enabled, each constraint accounts for 50% of the total edge score. Region of Interest (ROI) Most tool position parameters can be set through the Region of Interest section of the tool interface. The following are the parameters that define the tool region of interest:
ACEUser's Guide, 3.6.x, 18316-000 Rev A Page 365