Adaptive Fault-tolerant and Anti-disturbance Attitude Control of the Reconfigurable Modular CubeSat

This paper addresses the dynamical coupling and attitude control problems caused by the large-scale abrupt changes of the system mass characteristics and the relative motion of the sub-body during the autonomous reconfiguration of the modular satellite in orbit, the attitude dynamics equations of the reconfigurable modular CubeSat system with time-varying mass characteristics parameters are derived. An improved adaptive fault-tolerant anti-disturbance control algorithm that does not rely on an accurate dynamics model and converges quickly in finite time is also proposed based on the composite control idea. In the attitude control of modular CubeSat with large external disturbances and large range of moment of inertia time variation, the method has a faster convergence speed and higher accuracy than the traditional sliding mode control. Without any fault detection and diagnostic information, the method is able to achieve fast and highly accurate attitude adaptive fault-tolerant control in the presence of large disturbances and actuator time-varying, stochastic-type faults through real-time observation of total disturbances inside and outside the system. The final simulation results verify the effectiveness and reliability of the method.