火箭上升段滚动时域制导控制一体化设计

Receding Horizon Integrated Guidance and Control Design for Rockets in Ascent Phase

针对传统火箭上升段制导与姿态控制系统分离设计无法最大程度优化控制精度、控制量需求等系统整体控制性能的问题,提出一种基于凸优化的滚动时域制导控制一体化(IGC)设计方法。首先建立反映质心运动和绕质心运动耦合关系的IGC模型并对其进行反馈线性化获得面向控制的线性模型。然后考虑控制约束,将上升段IGC问题建模为最优控制问题,基于凸优化理论设计滚动时域控制器。该方法基于滚动时域控制(RHC)策略中反馈校正和滚动优化的思想,可以及时弥补模型误差和外部干扰等造成的不确定性;同时利用凸优化算法计算复杂度低、求解简单的优势,有效解决了含控制约束的复杂优化问题的求解。基于李雅普诺夫稳定性理论证明了闭环系统的稳定性。数值仿真校验了该滚动时域控制方法的有效性和鲁棒性;并且仿真结果表明,火箭上升段IGC设计比传统分离设计制导精度更高、控制量需求更小且姿态变化更加平缓。

A method of receding horizon integrated guidance and control( IGC) based on the convex optimization for rockets in the ascent phase is proposed for that the traditional separation design of the guidance and attitude control systems cannot achieve the optimal performance of the overall system. Firstly,the IGC model reflecting the coupling between the guidance and control loops is established and linearized by the feedback linearization. Then,the ascent IGC problem is modeled as an optimal control problem. A receding horizon controller based on the convex optimization theory is designed.The method can make up for the uncertainty caused by the model error and external interference timely based on the idea of feedback correction and receding horizon optimization of the receding horizon control( RHC) strategy. Meanwhile,the complex optimization problem with the control constraints can be solved effectively based on the advantages of low computational complexity and simple solution of convex optimization algorithm. The closed-loop stability of the IGC system is proved based on the Lyapunov stability theory. The numerical simulation verifies the effectiveness and robustness of the proposed method. And the simulation results show that the IGC design has higher guidance precision,smaller control requirements and smoother attitude angle change than the traditional separation design.