This article deals with identification of nonlinear dynamics and active control of boring bar chatter. A control system with unidirectional actuation is proposed, which consists of an accelerometer sensor that monitors the cutting tool vibrations as well as an electrodynamic shaker that exerts a controllable force to a boring bar in the radial direction. The forward path model for actuator–boring bar assembly is identified using the fundamental concepts of system identification. A novel parameter-varying transfer function is suggested to model the nonlinear dynamics of forward path, which originally stems from the cutting tool structure. The proposed model describes the variations of system’s output response with respect to frequency and amplitude of input excitation. The identified dynamic model is then utilized for model-based controller tuning. The chatter control system utilizes a Direct Velocity Feedback (DVF) controller, and the optimal control gain is computed based upon the disturbance rejection criterion. It is confirmed that the performance of optimally tuned DVF controller does not depend on variations of forward path dynamics. The practical performance of optimal controller is experimentally verified by conducting impact tests as well as cutting tests on Aluminum alloy 6063-T6. According to the obtained results, the dynamic stiffness of active cutting tool is significantly improved by 20-fold. Moreover, chatter is perfectly attenuated around the fundamental mode of boring bar. The DVF controller efficiently attenuates the vibrations by 70 dB. Finally, the viability of using an active cutting tool with embedded electromagnetic damper is studied for industrial applications.

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