Magnetic actuator for active damping of boring bars

This paper presents a new, noncontact magnetic actuator instrumented with fibre optic displacement sensors. The actuator is composed of four identical electromagnetic units which are linearized with a novel design strategy. The magnetic force can be delivered in two radial directions for active damping of lateral modes of the boring bar. The actuator is manufactured and mounted on a CNC lathe. The bending mode of the boring bar is actively damped, and the dynamic stiffness of the system was increased significantly, resulting in chatter-free higher depth of cuts. The actuator has been experimentally tested in boring operations.