Online identification of resonance using extremum seeking control

Aiming to implement quick online identification of mechanical resonance, this paper presents a novel identification method based on extremum seeking control (ESC). The model of mechatronics servo system with resonance is established based on mechanism analysis firstly. The switching-based ESC scheme is designed to identify resonance frequency by introducing a band-pass filter with variable center frequency and a suitable cost function. In this scheme, the perturbation ESC and sliding mode ESC are combined reasonably via a switching law to improve the speed and precision of identification further. The proposed scheme is with less calculation burden and better real-time performance than traditional FFT-based identification method. Finally, its effectiveness are verified sufficiently by simulation.