航天器姿轨耦合非线性同步控制

研究航天器飞行稳定控制建模问题。航天器动力学模型的精确建立,要求采用单独建立轨道或姿态的模型无法满足任务高精度要求,从非线性相对轨道动力学方程和修正罗德里格斯参数(MRP)表示的姿态运动学方程出发,建立了航天器六自由度的相对耦合动力学方程。为了给出姿轨运动的基准,分别设计了航天器理想姿态和椭圆加指数接近轨道。针对耦合非线性动力学方程设计了非线性同步控制律,并通过Lyapunov证明闭环系统的全局渐近稳定性。通过仿真结果可以看出,非线性同步控制算法能使轨道和姿态误差逐步趋于零,为航天器姿轨耦合设计提供了依据。

Spacecraft Attitude and Orbit Coupled Nonlinear Synchronization Control

Precise dynamic model of spacecraft is essential for the space missions and should be completed successfully.Nevertheless,the independent orbit or attitude dynamic models can not meet high precision tasks.This paper developed a 6-DOF relative coupling dynamic model based upon the nonlinear relative motion dynamics equations and attitude kinematics equations described by MRP.In order to give the benchmark of attitude and orbit motion respectively,the ideal spacecraft attitude and the elliptical plus exponent track orbit were given.Nonlinear synchronization control law was designed for the coupled nonlinear dynamic model,whose close-loop system was proved to be global asymptotic stable by Lyapunov direct method.Finallly,the simulation results illustrate that the nonlinear synchronization control algorithm can robustly drive the orbit and attitude errors to converge to zero.