Active vibration control development in ultra-precision machining

This study presents a combined feedback-feedforward adaptive regulator applied to an active vibration control tool holder platform to contain the effect of machining vibrations. The proposed mechatronic solution can be integrated in a milling machine tool as an interface between the beam (Z-axis) and the tool holder. The aim is to counteract vibrations in the broadband frequency range (100 Hz-900 Hz), controlling the tool position in real time. The active vibration control system is based on the harmonic steady-state concept due to the sinusoidal representation of the disturbance signals. The study focuses on the regulator architecture and the main logics applied to satisfy the required performance. A full investigation is executed through simulations and experimental campaigns, proving the disturbance reduction. The active vibration control system is implemented on a 4-axis machine tool and validated using multitonal disturbances. The system is evaluated in compensating a set of undesired effects, such as vibrations generated by unbalanced tools or hard material cutting processes. The obtained results show a maximum reduction of the vibration amplitude by 43.7% at the critical frequency.