匹配条件不满足的六旋翼无人机故障重构方法

Six-rotor UAV faults reconstruction method when the observer matching condition is not satisfied

针对六旋翼无人机(unmanned aerial vehicle,UAV)系统,首先根据动力学原理建立存在执行机构故障的无人机状态空间模型,并考虑无人机在实际飞行过程中受到外界干扰的影响。为了实现执行器故障重构(估计),把故障作为未知输入,通过矩阵变换将其作为系统状态的一部分,将原系统转化为一个不显含故障的增维系统。针对增维系统,构造Luenberger观测器来重构系统状态和执行器故障。由于所建立的无人机状态空间模型不满足未知输入观测器匹配条件,不能对其直接设计未知输入观测器进行观测,因此提出一种辅助输出构造方法突破观测器匹配条件的限制。对于外界干扰的影响,采用的方法对其进行抑制。最后的数值仿真验证了方法的有效性。

The actuator fault of six-rotor unmanned aerial vehicle(UAV)system is discussed in this paper.Firstly,according to the dynamic model,a state space model of UAV system with actuator faults is established,considering the external disturbance during the actual flight.For reconstruct or estimate the actuator faults,the faults are considered as unknown input.Thus,the original system is transformed into an augmented nonlinear system which contains no faults.A Luenberger observer is designed for the augmented nonlinear system to estimate both the state and the faults simultaneously.Since the model is not satisfied with the observer matching conditions(OMC),a method of the auxiliary output construction is presented to break the OMC.The robust optimization method is used to reduce the influence of external disturbance.The numerical example shows the effectiveness of the proposed method.