固定翼无人机自适应滑模控制

Adaptive sliding mode control for fixed-wing unmanned aerial vehicle

摘要:

针对固定翼无人机的姿态和速度控制中存在不确定和外部扰动的问题，设计自适应超螺旋滑模干扰观测器和控制器，实现了固定翼无人机对速度指令和姿态指令的有限时间精确跟踪.首先建立固定翼无人机速度模型和基于四元数的姿态误差模型；进而在该模型的基础上针对无人机飞行过程中的外部扰动和不确定问题，采用自适应超螺旋滑模算法设计干扰观测器对干扰和不确定进行快速估计，并在此基础上设计多变量超螺旋控制器使固定翼无人机快速、精确地跟踪期望的速度和姿态指令；最后基于Lyapunov理论证明了该系统的稳定性.仿真结果表明：所提出的综合控制策略可以实现固定翼无人机速度与姿态的快速精确跟踪并具有良好的鲁棒自适应能力，而且针对无人机不同的飞行指令，使用该控制策略都能使无人机快速稳定的达到预期目标.

Abstract:

Adaptive super-twisting sliding mode observer and controller are proposed for velocity and attitude control of fixed-wing unmanned aerial vehicle (UAV) which has been challenged by the presence of uncertainty and external disturbance. Firstly, the velocity model and quaternion-based attitude error model of fixed-wing unmanned aerial vehicle were established. Then the adaptive super-twisting sliding mode disturbance observer was designed to approximate system disturbance and uncertainty. On this basis, a super-twisting sliding control scheme was proposed to track desired commands of velocity and attitude of UVA. Finally, the stability of the system was proven by Lyapunov theory. The simulation results verified that the integrated control scheme made the UVA track desired commands fast and accurate, and had the excellent robust adaptive ability. The control strategy could also be used to quickly and steadily achieve the expected goal of unmanned aerial vehicles for different flight commands.