Attitude tracking control for fractionated spacecraft with actuator failures under adaptive event-triggered strategy

In this paper, two event-triggered algorithms are investigated to reduce the consumption and occupation of system resources for attitude tracking control of spacecraft system under external disturbances, model uncertainties, actuator failures, and limited communication. The first robust controller is designed with the triggering condition based on a time-based exponential function that has a dynamically decreasing trigger threshold. To improve the first controller, the second controller with the adaptive triggering condition based on a time-based exponential function is established to facilitate the realization of a comprehensive combination of feedback compensation mechanism and event-triggered control theory. It follows from the theoretical analysis that asymptotic convergence and Zeno-free are achieved under the proposed controller. Simulation results are provided to verify the effectiveness of the developed adaptive event-triggered fault-tolerant control laws.