This article presents a 6-DOF attitude-orbit synchronous control problem for the space circumnavigation (SCN) mission with parameter uncertainties, time-varying uncertainties, and input constraints. In particular, from the perspective of engineering application, time-varying measurement uncertainties are taken into account of the 6-DOF attitude–orbit coupling kinematics and dynamics, and the analytical solution of the desired attitude is derived based on the measured relative orbit information with measurement uncertainties. To drive the active spacecraft approach to the faulty target safely, a time-varying exponential prescribed convergence boundary is introduced into the sliding surface. A finite-time disturbance observer is involved in equivalent tracking errors for compensating the mismatched uncertainties. In addition, an auxiliary system is designed to overcome the instability danger caused by input constraints. The stability of the controlled system is discussed in the nonautonomous finite-time stable framework, which is proved via Lyapunov analysis that the attitude-orbit tracking errors converge to the equilibrium within finite time. The simulation experiment with mismatched uncertainties and prescribed constraints shows the superiority of the designed control scheme.

中文翻译：

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具有输入约束和测量不确定性的空间环球航行任务的有限时间规定性能控制


本文提出了具有参数不确定性、时变不确定性和输入约束的空间环航（SCN）任务的六自由度姿态轨道同步控制问题。特别是，从工程应用的角度出发，考虑了六自由度姿态轨道耦合运动学和动力学的时变测量不确定性，并根据实测相对轨道信息推导了期望姿态的解析解：测量不确定度。为了驱动主动航天器安全地接近故障目标，在滑动表面中引入了时变指数规定的收敛边界。有限时间扰动观测器参与等效跟踪误差以补偿失配的不确定性。此外，还设计了辅助系统来克服输入限制造成的不稳定危险。在非自治有限时间稳定框架下讨论了受控系统的稳定性，通过Lyapunov分析证明了姿态轨道跟踪误差在有限时间内收敛到平衡状态。不匹配不确定性和规定约束条件下的仿真实验表明了所设计的控制方案的优越性。