Xavier BEUDAERT

• Emmanuel DUC, Professor at IFMA - Clermont-Ferrand, Reviewer
• Jean-Yves HASCOET, Professor at Ecole Centrale Nantes, Reviewer
• Didier DUMUR, Professor at Supélec - Gif-sur-Yvette, Examiner
• Richard BEAREE, Associate Professor at ENSAM Lille, Examiner
• Sylvain LAVERNHE, Associate Professor at ENS Cachan, Co-supervisor
• Christophe TOURNIER, Professor at ENS Cachan, Supervisor

Keywords:
Open CNC, High Speed Machining, 5-axis milling, jerk, smoothing, feedrate interpolation, geometrical deviations.

Abstract:

The manufacturing process reaches maturity concerning Computer Aided Manufacturing and cutting process performances. Nowadays, major improvements are linked to the optimization of the Computer Numerical Control and its interactions with the rest of the manufacturing process. The aim of this thesis is to develop the basic components of a CNC in order to optimize the 5-axis high speed manufacturing process of complex surfaces.The realization of the new CNC requires the development of algorithms which transform the machining program in command setpoints for the machine drives. The first part of this thesis allows to round the 5-axis discontinuities generated by the linear tool path interpolation commonly used. Then, a feedrate interpolation algorithm computes the trajectory while respecting the kinematical constraints of the machine and especially the jerk of each axis.

The implementation of this work allows to control a 5-axis high speed machine with an Open CNC. Hence, the technological barriers that prevent CNC optimizations are removed and the manufacturing process is under control from CAD/CAM to axis displacement.

The complete control over the CNC offers the possibility to define the tool path exactly from Computer Aided Design entities without introducing any geometrical deviations generally induced by standard NC code. The direct interpolation of the trajectory on the machined surface significantly improves the quality and the productivity of complex surface machining. The PREMIUM-OpenCNC allows to prove experimentally the efficiency of this work and opens new ways for future manufacturing process improvements.