A study on virtual reality of NC programming for free-form surfaces

When we generate the cutter path for free-form surfaces by a CAM system, we have to minimize the aircut of it and to ensure the accuracy of the machined products. But it is very difficult for the conventional CAM system to set the adequate cutting condition and to generate the path only for the part to be cut. On the other hand, a profiling machine has been commonly used by die-manufacturers, because it enables the workers to directly generate the cutter path during monitoring the cutting situation. However a profiling machine needs the master-model of product and the accuracy of the cutter path is not high. Therefore we introduce the virtual reality into NC programming system for free-form surfaces. And an accurate virtual profiling system without master-models was realized. The worker can manually profile the model in the computer and can generate NC data for free-form surfaces by using the proposed system. In this paper, the construction of the virtual profiling system is described. The virtual profiling system consists of a bilateral master-slave system which has a 3DOF orthogonal direct drive manipulator, a profiling simulation software, and a cutting simulation software. The virtual profiling system can generate the cutter path for free-form surface models in real time with the accuracy of ±0.1μm.