考虑落角约束和气动不确定性的固定时间制导控制一体化设计方法

Fixed-time Integrated Guidance and Control for Impact Angle Constrained Interception with Multiple Uncertainties

文中研究落角约束和气动不确定性条件下的机动目标制导控制一体化设计问题。首先,将目标的加速度和气动不确定性考虑为有界的外部扰动。其次,将典型的反步法与动态曲面控制技术相结合,提出了一种固定时间滑模控制方法来解决制导控制一体化设计问题,并通过引入固定时间微分器有效避免反步法中存在的“微分膨胀”问题。然后,借助于固定时间稳定性理论对闭环系统进行了稳定性分析,表明所提方法能够使所有误差信号在任意初始条件下实现半全局固定时间一致最终有界稳定。最后,通过仿真验证了所提方法的有效性。

This paper considers the integrated guidance and control(IGC)problem for maneuvering target interception with impact angle constraint and uncertain aerodynamics.The target’s acceleration and uncertain aerodynamics are considered as bounded external disturbances.By combining the typical backstepping idea with dynamic surface control(DSC)technique,a fixed-time sliding mode control approach is presented to address the IGC law design problem and the inherent problem of“explosion of complexity”in typical backstepping design is efficiently avoided by introducing a fixed-time differentiator.Furthermore,fixed-time stability theory is presented to carry out the stability analysis showing that with the proposed control scheme all signals in the sliding mode system can achieve semi-globally fixed-timely uniformly ultimately bounded stabilization independent of initial conditions.Finally,the superiority of the proposed IGC law is demonstrated by simulation results.