VERNE -: a five-axis parallel kinematics milling machine

Ten years ago a new kind of machine tool was presented in Chicago, based on parallel kinematics architectures. Since then, many of these parallel kinematics machines (PKMs) have been developed around the world. Their main interest lies in their high dynamic characteristics, which could help in going faster in high-speed milling. In order to develop high-speed milling on PKM tools and to highlight their potentialities, the French laboratory IRCCyN is now equipped with the VERNE. This PKM tool has been developed by the Spanish company Fatronik. However, the high-speed milling production process is a complex task, in which a great number of parameters influence the final precision of the part and the productivity of the machine. For example, the NC (numerical control) and computer-aided manufacturing (CAM) parameters (feed for-ward, milling strategies, etc.), the piece geometry, the machine structure, the tool, etc., have a direct consequence on the final part. Hence, a method has been developed in order to check the capability of the machine (either serial or parallel) in milling, which relies on two approaches. The first one is an experimental approach (either using a coordinate measuring machine or acquiring the output axis encoders), while the second one is a simulated approach. After introducing the kinematics of the VERNE, the experimental approach performed so far will be presented.