Chatter suppression in ram type travelling column milling machines using a biaxial inertial actuator

Productivity of heavy duty milling processes is limited by chatter vibrations related to the flexibility of the machine tool structure. One of the solutions is to add damping to the structure using vibration absorbers. However, the dynamic behaviour of these machines changes depending on their position in the workspace. Moreover, the critical modes have different displacement directions. Hence, in order to suppress chatter vibrations, a biaxial active actuator has been developed. In this work, the possible control strategies are analysed and the results of experimental tests of the biaxial actuator are shown. Important stability increase was obtained in real milling operations.