Distributed Event-Triggered Formation Control of MASs With Parametric Uncertainties Under a Directed Graph: Application to Multiple Quadrotors

In this article, the leaderless formation problem of multiagent systems (MASs) with parametric uncertainties under a directed graph is investigated via introducing a distributed model reference adaptive event-triggered control (MRA-ETC) method. Specifically, to simultaneously eliminate the influence of the parametric uncertainties and reduce the communication burden among agents, a reference model using the predicted relative state information initialized by intermittently collected state information of neighbors as input and a self-contained adaptive estimator of uncertainties are constructed, where the transmitted information is asynchronous and intermittent. Armed with this reference model, an MRA formation algorithm is designed such that the MASs with parametric uncertainties reach leaderless formation asymptotically. A novel graph-based Lyapunov function is proposed to analyze the formation convergence. The Zeno behavior is further excluded by giving a lower bound of the minimum transmission interval for each agent. Finally, the effectiveness of the proposed algorithm and its practical feasibility are verified through experiments on a group of Crazyflie 2.0 quadrotors.