Abstract: ANC preliminary design paradigm is put forward through analyzing and calculating the normal unit vector of the NURBS surface. By exploiting typical modules, such as the translating module, the rotating module and the base module, the NC movement conceptual configuration is precisely expressed. This conceptual module is recorded in the computer. By the introduction of agent, the creative preliminary design is realized and the interpolation control technique is completed in the course of grinding wheel dressing.

Key words: NC system, NURBS, creative design, normal vector