Modified ADRC Design for Rigid-flexible Coupling Rotary Stage with Filters

High-precision rotary stages are applied in many fields, but the bearing friction has a negative impact on tracking performance. Rigid-flexible coupling rotary stage, a novel structure for rotary stage, can convert the friction disturbance into elastic force with flexure hinges. In order to avoid the effect of elastic force, active disturbance rejection control (ADRC) is adopted in this paper for its excellent disturbance rejection ability and independence of accurate modelling. In view of the resonance and high-frequency noise of the system, notch and lead filters are combined with ADRC, which is called modified ADRC. The experimental results show that the modified ADRC has a good effect on eliminating elastic force disturbance, and also has the ability to suppress resonance and high-frequency noise.