An international conference connecting people
in CAD research, education and business
Bookmark and Share
Copyright (C) CAD Solutions, LLC. All rights reserved.
Proceedings of CAD'17, 2017, 37-43
Integration of T-spline within STEP-compliant CNC

Gang Zhao, Oleksandr Zavalnyi, Yazui Liu, Wenlei Xiao, Beihang University

Abstract.  Advanced freeform surface machining usually refers to the recently most used surface representations such as NURBS and T-spline. Their definitions in STEP/STEP-NC provide the possibility to integrate them with the STEP-compliant CNC (STEP-CNC) systems. Due to the advantages of less control points, gap-free model representation capability, and localized refinement operations against NURBS, T-spline models became more and more attractive for manufacturing in the research field. The fact that NURBS surfaces can be converted into T-spline models allows to consider T-spline as an optimal solution for the integration of advanced freeform surface machining technologies within STEP-CNC. This paper discusses the representation of T-spline within STEP-NC and issues of toolpath generation on T-spline surfaces in context of the machining strategies defined in ISO 14649-11. Then some results of toolpath generation process are presented. At the end, we show the possibility of integration of T-spline with a prototype STEP-CNC system that provides on-line toolpath generation capability.

Keywords. T-spline, STEP-NC, STEP-CNC, Freeform surface machining

DOI: 10.14733/cadconfP.2017.37-43