Adaptive Predefined-Time Event-Triggered Control for Attitude Consensus of Multiple Spacecraft With Time-Varying State Constraints

In this article, a predefined-time event-triggered attitude consensus control problem is investigated for multiple spacecraft with time-varying state constraints. A backstepping-based control scheme for achieving a consensus in spacecraft attitudes within a predefined time is presented. To enhance the efficiency of communication resource utilization, an event-triggering mechanism is designed by employing a saturation function. This mechanism allows for the application of three existing triggering strategies in multiple spacecraft systems. Then, a novel asymmetric fractional barrier Lyapunov function (BLF) guarantees adherence to time-varying constraints while addressing the issue of excessive control amplitude associated with large constraint boundaries in conventional logarithmic BLFs (LBLFs). This enables the proposed approach to handle both constrained and unconstrained scenarios. The efficacy of the proposed control strategy is illustrated through numerical simulation examples.