Contact — 2D Models
When you click > 
Interface, you are prompted to specify two edges or curves that you want to use for the 2D models. Be sure the second edge or curve is near and approximately parallel to the first.
Interface, you are prompted to specify two edges or curves that you want to use for the 2D models. Be sure the second edge or curve is near and approximately parallel to the first.After you select the edges or curves, Creo Simulate checks for the following on a pass or fail basis:
• The distance between the edges or curves must be less than one half of the average of the lengths of the two edges or curves.
• At one or more points along the first edge or curve, the normal to the first edge/curve must intersect the second edge or curve.
• A contact associated with the two selected edges or curves cannot already exist.
Creo Simulate also checks to see if any points in common between the two selected edges or curves will prevent the edges or curves from moving completely apart during an analysis. If there are any such points, a warning box appears and you should respond appropriately.
For each valid pair of curves, a contact icon is placed at the point where the edges or curves are closest to each other, oriented along the point of closest approach.