Event-triggered attitude synchronization of multiple rigid body systems with velocity-free measurements

Abstract

In this paper, an attitude synchronization problem with velocity-free measurements is investigated for multiple rigid body systems under event-triggered mechanism. To avoid the angular velocities in the control design, an auxiliary system is constructed for the indirect asymptotic estimation of angular velocities, which provides the necessary damping for the closed-loop system. The event-triggered attitude protocol is proposed with a clock-based triggering strategy, and the continuous communication and monitoring requirements among rigid bodies are removed. The convergence of synchronization is analyzed based on a positively invariant set contained in SO(3), which inherently avoids the singularity problem or non-uniqueness issue for the attitude representation. Furthermore, based on an invariant-like principle, we extend the topology graph to a switching topology under an average dwell-time condition. A numerical simulation is conducted to show the effectiveness of the proposed control strategy.