Output Formation Tracking via Distributed Observer and Distributed Internal Model Approaches with Application to Networked Quadrotors and Mobile Robots

Over the last decade, the distributed observer and distributed internal model approaches have emerged as theoretically sound solutions to the cooperative output regulation problem, an extension of the conventional output regulation problem to multi-agent systems (MASs). In this paper, we focus on output formation tracking (i.e., leader-following formation) of heterogeneous MASs via distributed observer and distributed internal model approaches. We first define the considered output formation tracking problem and derive sufficient conditions for its solvability using a distributed observer-based dynamic state feedback control law and a distributed internal model-based dynamic state feedback control law. Step-by-step guides for synthesizing the control parameters of each control law are then provided. To demonstrate the theoretical results and compare the formation-tracking performance and robustness of both approaches in practice, we finally conduct a simulation and experimental study on a heterogeneous MAS composed of three quadrotors and a mobile robot in an indoor experimental facility. The results of this multi-vehicle study align with the expected pros and cons of both approaches.