Interpolation of 3D segments obtained through a trinocular stereo process is achieved by using a 2D Delaunay triangulation on the image plane of one of the vision system cameras. The resulting two-dimensional triangulation is backprojected into the 3D space, generating a surface description in terms of triangular faces. The use of a constrained Delaunay triangulation in the image plane guarantees the presence of the 3D segments as edges of the surface representation.