Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

Designing advanced machine tools

The project deals with the design of the motion control unit for machine tools of the next generation, using the most advanced design techniques. An architectural framework has been worked out to define the architecture of Motion Control Units for machine tools and the feasibility of using alternative materials and/or structural shapes for the Motion Control Units of machine tools has been studied. A comparative study into the different slideway technologies and their underlying tribological principles has been carried out in addition to the investigation of new and hybrid techniques in bearing and damper design which allow for active, online, compensation of slideway dynamics. A comparative study of ballscrew drives, rack and pinion drives and direct linear motor drives reveals that the target performances can only be achieved with linear motor drives. The linear motor solution also yields better accuracy and repeatability and a higher bandwidth of the servo system. A general, 'decoupled' method has been derived to optimize the motor transmission unit in a traditional rotary motor feeddrive system and 3 representative test set ups have been developed and built. Reliable dynamic identification schemes have been developed and applied to the test set ups and a generic control scheme has been developed and applied to the test set ups as well as to an existing machine. Also, a preliminary design of a 10 000 N linear motor has been made to assess the feasibility of its use. A generic numerical control structure for very high speed milling has been proposed. The generic control scheme has been implemented on an existing high speed milling machine, making use of the existing controller. An average reduction of the tracking errors with a factor 5 have been achieved. Finally, 'mechatronic compiler' for the design of multitechnological systems has been developed.