SMART MATERIALS IN DYNAMIC ERROR ATTENUATION OF CUTTING TOOLS

摘要

Vibration suppressions techniques in cutting tools can save old machines and enhance design flexibility in new manufacturing systems. The finite element method is employed to investigate structural stiffness, damping, and switching methodology under the use of smart material in tool error attenuation. This work discusses the limitations of using lumped mass modeling in toolpost dynamic control. Transient solution for tool tip displacement is obtained when pulse width modulation (PWM) is used for smart material activation during the compensation of the radial disturbing cutting forces. Accordingly a Fuzzy algorithm is developed to control actuator voltage level toward improved dynamic performance. The required minimum number of PWM cycles in each disturbing force period is investigated to diminish tool error. Time delay of applied voltage during error attenuation is also evaluated. Toolpost static force-displacement diagram as required to predict voltage intensities for error reduction is tested under different dynamic operating conditions.