考虑执行器性能约束的刚体航天器鲁棒姿态跟踪控制

针对存在模型不确定性、外界干扰力矩和执行器性能受限等约束条件下的刚体航天器姿态跟踪控制问题进行研究,并基于滑模控制、反步控制、自适应控制、辅助系统和动态面控制等方法设计相应的鲁棒姿态跟踪控制算法.利用自适应控制实现了对具有多项式形式上界函数的系统未知不确定性进行在线估计和补偿;通过建立描述执行器动态特性的低通滤波模型,并结合辅助系统方法,以确保执行器输出控制力矩的幅值及其变化率均满足一定的饱和约束;通过引入动态面控制法,避免期望虚拟控制信号的一阶导数项直接出现在控制器中,简化了闭环姿态跟踪控制器的设计形式.最后,通过数值仿真验证了所提出控制算法的有效性和可行性.

Robust attitude tracking control of rigid spacecraft considering control input constraints

The rigid spacecraft attitude tracking control problem in the presence of the modeling uncertainty, external disturbance and input constraints is investigated in this paper, and a robust attitude tracking control algorithm is designed based on the combination of the sliding mode control, backstepping control, adaptive control, auxiliary system and dynamic surface control approaches. Within the proposed controller, the adaptive control technique is utilized to estimate and compensate for the unknown system uncertainty on line. A dynamic model in a low pass filter form is built up for the onboard actuators, which is then associated with the auxiliary system method to satisfy the control input magnitude and rate saturations. Moreover, the dynamic surface control(DSC) method is employed to avoid the calculation of the differentiation of the virtual control signal and simplify the closed-loop attitude tracking controller. Finally, digital simulations are conducted to further demonstrate the effectiveness and feasibility of the proposed controller.