Abstract:The spindle is the core component of the numerical control machine tool. The vibration caused by the mass imbalance seriously affects the machining accuracy of the machine tool. To suppress the spindle unbalanced vibration, it needs to accurately extract feature of the vibration signal. To identify the unbalanced vibration amplitude and phase of the spindle system, a feature extraction method based on the allphase fast Fourier transform is proposed. The all phase fast Fourier transform can accurately extract the phase and amplitude of the signal by using spectrum analysis function. This method is compared with other three methods to extract the vibration feature of the signal collected by simulation and experiment. Results show that the allphase Fourier transform can achieve better vibration amplitude and phase accuracy and stability. The accuracy of the vibration phase after extraction can reach 97%, and the dynamic balance vibration suppression experiment can be reduced by 6521% after extraction. The effectiveness of the method is further verified.