针对高超声速飞行器的姿态控制问题,考虑系统模型不确定性以及外界干扰的影响,基于快速终端滑模设计了连续的姿态跟踪控制器。将飞行器姿态控制系统模型按时间尺度划分为快回路和慢回路,其中慢回路的控制器设计目标是给出期望角速度作为快回路的制导指令,快回路控制器的设计目标是给出系统需求的控制力矩。基于有限时间控制理论分别针对各回路设计了连续的快速终端滑模姿态控制器,通过严格的数学证明,该控制器可以在系统模型存在不确定性以及外界干扰的情况下,使得姿态跟踪误差在有限时间内收敛。仿真结果表明本文的控制算法可以在短时间内使飞行器的姿态角均以较高的精度收敛至期望状态,且三个方向的控制力矩曲线均变化平滑,无抖振现象产生。
Regarding the attitude control issue in hypersonic aircraft,and considering system model uncertainties and external disturbances,in this paper we propose a continuous attitude-tracking controller using a fast terminal sliding mode. The attitude control system model for aircrafts is divided into fast and slow loops,based on the time scale. The design goal of the slow loop controller is to provide the expected angular velocity as a guidance command for the rapid loop,and the design goal of the rapid loop controller is to provide the control torques required by the system. Based on the finite-time control theory,we designed a continuous fast terminal-sliding-mode attitude controller for each loop. Based on the strict mathematical proof,the controllers can converge attitude follow-up errors within a finite period of time,given existing uncertainties regarding the system model and external disturbances.Simulation results show that the proposed control algorithm can converge the attitude angle of aircrafts to the expected status with relatively high precision and in short time period. In addition,the control torque curves in three directions all change smoothly without any chattering phenomenon.