Distributed Cooperative Attitude Control For Multiple Spacecrafts Based On Sliding Mode/event-triggered

Multiple spacecraft with a formation configuration can achieve the complex space missions by effective coordination between each spacecraft through communication, and it has a broad development prospect in the aerospace. While there are some unfavorable factors when the spacecraft formation flying, such as parameter uncertainty, external disturbance, actuator faults and saturation. So, in this study, we investigate the attitude coordination control problem for multiple spacecraft formation from the following aspects.Firstly, the attitude coordination control law of multiple spacecraft formation is investigated in the presence of external disturbance and paremeter uncertainty. Based on that the integral sliding mode has the advantage to realize the global robustness for the uncertainty, and in the premise of the known upper bound of uncertainty and external disturbance, an integral sliding mode attitude coordination controller is proposed. Further, combining the adaptive control technology, and using the adaptive control law to estimate the upper bound online, an adaptive integral sliding mode control algorithm is designed, which can achieve the attitude consensus of the spacecraft formation while the priori requirement for the upper bound of polymerization disturbance is removed, and the simulation results has proved the effectiveness of the proposed control law.Then, in order to solve the attitude coordination control problem of multiple spacecraft formation in the presence of external disturbance, parameter certainty, actuator faults and saturation, based on the modified adaptive law, an attitude coordination control law with the input normalized neural network is investigated. A fault-tolerant control algorithm is proposed without using the fault information, which guarantees that each spacecraft can track the reference attitude and achieve the attitude consensus when only a subset of spacecraft can access to the common reference attitude. And the fault capability of the proposed control law has been proved by the comparative simulation.Finally, an attitude coordination control law is invesgated for spacecraft formation system with solving the communication restricted and periodic communication problem. Based on auxiliary variable and triggering function, an event-triggered attitude consensus controller is designed for spacecraft formation to achieve the consensus of the attitude and the asymptotical stability of the attitude velocity. Besides, to deal with the case of time-varying bounded disturbance, an adaptive event-triggered control law based on auxiliary veriable is studied to achieve the attitude consuesus with no Zeno behavior exhibited, which is proved by theory analysis and numerical simultation.