Abstract: Aiming at the improvement of machining stability, a new on-line chatter control method is presented, which is to actively adjust the machining dynamics in process based on the application of smart materials in manufacturing systems. For on-line chatter avoidance in boring a adaptive control system is given, which employs a novel design of the boring bar containing a smart material, electrorheological(ER) fluid. This control system successfully suppress boring chatter by automatically adjusting the dynamics of the bar according to the information from the monitored sensor signal.

Key words: Electrorheological fluids, Machining chatter, Nonlinear dynamics, On-line control Artificial neural networks