On Dual Compensation to Disturbances and Uncertainties for Inertially Stabilized Platforms

This paper focuses on disturbances and uncertainties rejection control for the nonminimum-phase inertially stabilized platforms on moving bases, which suffers from serious disturbances and uncertainties. To stabilize the nonminimum-phase system, the standard disturbance-observer-based control method has to sacrifice the stability margins and disturbance rejection. The dual compensation disturbance-observer-based control method is proposed in this paper to ensure a stronger disturbance rejection performance. The two compensators of the proposed method have independent capabilities to reject the disturbances parallelly. The synergic compensators deal with much more disturbances than each of them separately due to their superimposed disturbance rejection. The proposed method doesn’t change the stability margins and tracking capabilities and open-loop characteristics. The analytical tuning laws for the proposed method are presented. The proposed method is verified in typical setups based on the gimbal and inertially stabilized laser control systems. Simulated and experimental results demonstrate that compared with the standard disturbance-observer-based control method, the proposed method can negate much more disturbances without changing the stability margins. The simulation and experimental results show the effectiveness and superiority of our method.