升力式再入飞行器体襟翼姿态控制方法

Body-flap attitude control method for lifting re-entry vehicle

针对升力式再入飞行器体襟翼控制三通道时的非最小相位问题,设计了一种姿态输出跟踪控制方法。选择合理的局部微分同胚,将姿态输入-输出模型转换为正则形式并得到内动态。通过对内动态进行稳定性分析并提出系统非最小相位特性的判据,采用此判据可判定当存在副翼反效时该输出跟踪控制问题为非最小相位控制问题。针对该问题,首先依据内动态与外部动态的线性相关度将正则模型分解为最小相位子系统(纵向通道)和非最小相位子系统(横侧向通道),然后运用动态逆控制技术对2个子系统分别设计状态反馈控制器,最后基于Lyapunov方程和最小范数控制策略在非最小相位子系统中引入非线性辅助控制项以镇定整个姿态控制回路。仿真结果表明了在仅有体襟翼控制的情况下该控制方法能够精确跟踪控制指令并镇定内动态。

An attitude output tracking control method is proposed for a lifting re-entry vehicle with a nonminimum phase property. Such problem is caused by body flaps which are the only actuators to be used for controlling three-channel. By using local differential homeomorphism,the attitude input-output model is transformed into normal form,and internal dynamics are obtained. A criterion of non-minimum phase is developed by analyzing the internal dynamics＇ stability,and this criterion is used to predict the non-minimum phase phenomena when aileron reversal exists. To solve this problem,the normal form is decomposed into a minimum phase subsystem（ longitudinal channel） and a non-minimum phase subsystem（ lateral-directional channel）.And then,dynamics inversion is used to design the state-feedback controllers for these two subsystems. Moreover,a nonlinear auxiliary control input is introduced to stabilize the overall attitude control loop by both Lyapunov function and a minimum-norm control strategy. Simulation results demonstrate that in the case where body flap actuators are employed for attitude control,the control commands can be tracked and internal dynamics can be stabilized by the proposed method.