A Surface Parameter-Based Method for Accurate and Efficient Tool Path Generation
Keigo Takasugi*, Naoki Asakawa**, and Yoshitaka Morimoto***
*Kanazawa Institute of Technology, Ogigaoka 7-1, Nonoich, Ishikawa, Japan
**Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, Ishikawa, Japan
***Kanazawa Institute of Technology, 3-1 Yatsukaho, Hakusan, Ishikawa, Japan
Along with the increasing need for multi-axis and multi-tasking machining tools for the machining of complex free surfaces, the importance of CAM applications related to the accuracy of the free surfaces has increased dramatically. The machining accuracy and surface integrity of a product depends not only on the performance of the machining tool itself but also on the tool path generated by CAM. At present, there is a trade off between numerical calculation errors and cost in CAM. There is no calculation method that satisfies both sides. Of particular importance is the fact that the cost increases exponentially with the rank of the free surface. Therefore, this paper proposes a new method of generating tool paths efficiently; it generates tool paths directly from 2-dimensional parametric space by using the parametric surface defined as a polynomial. We confirm that this method can reduce the cost and that the tool path can be generated by means of a simple calculation process, without considering singular points. Moreover, since commercial CAM kernels cannot accommodate to our method, we design and implement a new CAM kernel that can access the parametric surface directly in order to develop this method.
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