PROJECT TITLE :

Active Damping of Boring Bar Vibration With a Magnetic Actuator

ABSTRACT:

Boring bars with a large length-to-diameter ratio chatter below productive cutting conditions, which results in poor surface finish and violation of part tolerances. This paper presents an energetic damping methodology of boring bars with an in-house designed magnetic actuator. The actuator has been designed to possess a linear force output relative to the input current, and instrumented to regulate boring bar vibrations. Four different H∞ optimal controllers are designed to shape the boring bar dynamics and improve the chatter stability. The proposed active damping methodology is experimentally tested on a CNC lathe. The dynamic stiffness of the boring bar is increased significantly, leading to a important increase in the chatter-free material removal rates.