Intersection of Offset Surfaces of Parametric Patches

In this paper, we present a new method to calculate intersection curve of offset surfaces of two parametric surface patches. This method is based on the concept of normal projection and the intersection problem is formulated with a set of tensorial differential equations. The intersection is represented in the parametric spaces of the base surfaces and no offset surface approximation is needed. Numerical examples are presented for non-uniform rational b-spline (NURBS) surfaces to illustrate the effectiveness and efficiency of the proposed approach.