基于非线性最优反馈控制的远程拦截闭环制导

利用非线性最优反馈控制和伪谱轨迹快速重构技术,设计了一种有限推力空间远程拦截自适应闭环制导方法。首先建立了有限推力远程拦截最优制导问题模型,并给出了适用于该问题的非线性最优反馈控制求解原理。然后,将空间变轨动力学模型特点和伪谱法相结合,设计了基于状态量缩减的计算效率改进策略以提高轨迹优化的实时性。基于改进伪谱法进行连续轨迹快速重构,利用开环最优解形成闭环反馈,从而保证制导指令的实时更新,并通过引入控制逻辑对制导算法进行改进。时间最短远程拦截仿真表明,该闭环制导方法在保证任务指标最优性的同时,可以有效抑制J2摄动和计算误差的影响,具有较高的制导精度、自适应性和鲁棒性。

Nonlinear Optimal Feedback Control Based Closed-Loop Guidance of Long-range Intercept

An adaptive closed-loop guidance algorithm,which is based on nonlinear optimal feedback and rapid pseudospectral-based trajectory reconfiguration,is studied and proposed for long-range orbital intercept with finite thrust. The mathematic model is established for the optimal guidance problem,which can be solved through nonlinear optimal feedback control theory. Then,combining the characteristics of the dynamics model with the pseudospectral method,a computational efficiency refinement method with the reduced state parameters,is proposed to improve the efficiency of trajectory optimization. The modified pseudospectral method is used for the successive rapid trajectory reconfiguration such that the open-loop optimal controls are fed back to the system to update the guidance commands in real-time. A control logic algorithm is introduced to heighten the performance of the algorithm. The simulation results of long-range intercept indicate that the algorithm can not only supply excellent optimal solution for practical mission with high accuracy,but can manage J2 perturbation and computation error autonomously,adaptively and robustly.