Decoupled Control Of Two-degrees-of-freedom Gyroscope

Two-degrees-of-freedom gyroscope, which is the main component of gyroscope horizon indicator in flight control system of helicopter, is considered as the controlled plant in this paper. In order to meet the requirement of both actual usage and afresh usage via repetitious examination and repair, this paper focuses on the drift problem of gyroscope that due to some uncertain factors and the coupling problem of two-degrees-of-freedom gyroscope. Firstly, dynamic formulas of gyroscope under the ideal condition and the actual condition are derived. Sencondly, the Cross-Coupling Control (CCC) is put forward to solve the geometric coupling problem of two-degrees-of-freedom gyroscope. Finally, aiming at the dynamic coupling of two-degrees-of-freedom gyroscope, the theory of the forward feedback is applied. Meanwhile, Tracking Diffrentia (TD) is added to decouple the dynamics coupling and the geometric coupling of two-degrees-of-freedom gyroscope. However, there is some difference in result between theory and practice. The reason that the control accuracy can not reach request is given in this paper. The Active Disturbance Rejection Control (ADRC) technique is proposed by increasing the Extension-State-Observe (ESO). Comparing with the tradition PID, the ADRC based on CCC consumedly improves the control accuracy of two-degrees-of-freedom gyroscope. It assures the stability and high accuracy of its carrier and related system.