本文针对挠性卫星姿态机动和振动抑制问题,给出一种基于多项式平方和(sum of squares,SOS)的非线性局部镇定控制方法.根据姿态系统结构特征,在此基础上,采用SOS结合S-procedure理论,得出相应的非线性局部可镇定条件.该条件可借助有效凸优化工具进行检验,当优化问题可解时,可构造非线性姿态控制器的解析解.最后,将文中方法应用于某型挠性卫星姿态控制.仿真结果表明,在实现大角度姿态快速机动的同时,有效抑制了挠性附件振动.
Based on the polynomial sum of squares (SOS) techniques,a nonlinear local stabilization control approach is proposed for the problem of flexible satellite attitude maneuver and vibration suppression.According to the structural features of attitude system,a nonlinear local stabilization controller is developed and the complexity of attitude control design is reduced effectively by employing a separation principle for the reduced-order observer and state feedback.On this basis,the corresponding conditions of nonlinear local stabilization,which can be checked through convex optimization algorithms,are presented by using the SOS and S-procedure theory,and the analytical solution of nonlinear attitude controller can be constructed if the optimization problem is solvable.Finally,this method is applied to the attitude control of a flexible satellite and the simulation results show that both the fast large angle attitude maneuver and the vibration suppression are well realized.