基于滑模观测补偿的四旋翼飞行器鲁棒动态逆控制

摘要

四旋翼飞行器为欠驱动形式,其模型存在强耦舍、大不确定性的特征,需设计具有强抗扰和强鲁棒能力的控制器以提升四旋翼飞行性能.首先建立包含结构参数不确定性的四旋翼飞行器动力学模型,分析其特性并基于时标分离原则进行模型的双回路划分.利用小角度假设对模型进行线性化处理并求取模型的状态空间表达形式,给出满足不确定性区间内稳定控制要求的鲁棒控制律,并采用Lyapunov理论进行控制律的全局收敛性证明.为增强控制器的抗扰性,利用Super-twisting算法设计了滑模干扰观测器对外部扰动进行观测并予以补偿.仿真结果表明,所设计的基于滑模观测补偿的鲁棒动态逆控制器在应对较大结构不确定性和外部扰动情况具有良好的控制品质.%The model of quad-rotors is of under-actuation,strong coupling and large uncertainty,thus a controller of strong robustness and anti-jamming capability should be proposed to enhance the flight performance of quad-rotors.Firstly a dynamic model of quad-rotors containing structural uncertainty is deduced,which is separated into double loops based on time-scale separation after detailed analysis on its dynamical characteristic.Then linearization with assumption of small Euler angles helps derive a state space dynamic model.Considering stabling the quad-rotors under any possible structural uncertainty,a robust control law is given and its global convergence is proved through the Lyapunov theory.For the improvement of flight performance against external disturbance,we design a sliding-mode disturbance observer on the basis of the super-twisting algorithm so as to observe the perturbation and make compensation.Simulations under the condition of large structural uncertainty and external disturbance validate better control performance of the proposed controller.