Design and Validation of an Active Damping Device for Chatter Suppression on Flexible Workpieces

The apparition of self-excited vibrations known as chatter limits the productivity and accuracy of many industrial machining processes since they cause a reduction in the surface quality and in the lifetime of mechanical elements and tools. When large welded parts are machined, chatter vibrations are usually related to the flexibility of their relatively thin walls and special fixtures have to be designed in order to get a chatter free cutting process. The present paper proposes the design and validation of a novel active damping device attached directly to the workpiece surface by means of magnet and able to suppress chatter vibrations. The actuator introduces a force depending on the measured vibration to increase the damping of the flexible workpiece modes and hence increase the stability limit. The results obtained with this active device are demonstrated in industrial conditions.