基于微分包含的绳系卫星时间最优释放控制

TIME-OPTIMAL DEPLOYMENT OF A TETHERED SUBSATELLITE BASED ON DIFFERENTIAL INCLUSION

考虑系绳弹性的影响,建立了绳系卫星系统三维动力学模型,研究了在状态和控制约束下的绳系卫星非线性时间最优控制问题.为缩减系统变量,控制律设计没有采用通常的状态空间模型,而是基于二阶微分包含,将连续时间最优控制问题离散为大规模动态规化问题,最后通过数值模拟验证了该方法的有效性.

This paper presents the nonlinear time-optimal control for the three-dimensional deployment process of a tethered subsatellite model, which also takes tether elasticity and the mission-related state-control constraints into consideration. Instead of the commonly used state-space model, a second-order differential inclusion formulation is exploited in this study to achieve a significant reduction of the number of system variables. The optimal control is solved by discretizing the optimal control problem based on a direct algorithm, and numerically solving the resulting large-scale optimization problem via a nonlinear programming solver. The case studies in the paper well demonstrate the performance of the proposed strategy.