双星跟飞立体成像的构形保持控制

针对强干扰及输出饱和条件下微小双星立体成像的构形保持问题，提出一种基于观测器的抗干扰复合控制策略.根据立体成像双星跟飞运动机理，建立双星相对运动动力学模型；设计了一种自适应干扰观测器，可同时实现系统状态和干扰信息的在线估计，并采用Lyapunov稳定性理论和线性矩阵不等式技术给出观测器存在条件.采用极点配置方法改善观测器系统的动态性能，引入指数衰减因子提高控制器的收敛速度.考虑执行机构的输出饱和特性，提出一种加权PD+LQR反馈与干扰前馈补偿的复合控制策略，能够抑制未知干扰的影响，保证系统的动态和稳态性能，具备双星构形保持控制能力.仿真结果验证了所提算法的有效性. 

Configuration Keeping Control of Stereo Imaging with Dual-satellite Following Flying Formation

Aiming at the configuration maintenance problem of stereo imaging with micro double satellites under strong interference and output saturation, a composite anti-disturbance control strategy combining LQR optimal control and PD control is proposed. According to the relative orbit motion mechanism of dual-satellite following flying formation for stereo imaging, the dynamic modeling of relative motion is built with a dynamic analysis of double satellite following formation carried out, and the system motion state equation is obtained. Secondly, an adaptive disturbance observer is designed, which can estimate the system state and disturbance information at the same time. The existence condition of the observer is given by using Lyapunov stability theory and linear matrix inequality. In addition, the pole placement method is used to improve the observer dynamic performance, and the exponential attenuation factor is introduced to improve the convergence speed of the controller. Considering the output saturation characteristics of the actuator, a composite control strategy of weighted PD + LQR feedback and disturbance feedforward compensation is designed to suppress the influence of unknown disturbance and ensure the transient response and steady state performance of the system. Simulation results have verified the effectiveness of the proposed algorithm, which can provide configuration keeping control strategy for dual star stereo imaging.