Distributed Consensus For Non-linear Multi-agent Systems

In recent years, the distributed control for multi-agent systems has attracted manyresearchers from various disciplines of engineering and science due to the broadapplications of multi-agent systems in such areas as formation for mobile robotics,distributed computation, sensor networks, and network control. Consensus problem is thekey problem for the multi-agent systems. The goal of consensus problem is to desigendistributed control scheme for each agent driving the information or states of all agents toreach agreement. Because there are not many papers considering the consensus problemsfor nonlinear multi-agent systems, or the nonlinear consensus protocols for linearmulti-agent systems to get better profermances, this thesis mainly studies the consensusproblem for multi-agent systems with nonlinear dynamics, and designs nonlinear consensusalgorithm for linear multi-agent systems. The main contents and contributions can besummarized as follows:(1) For high-order multi-agent systems, we investigate the distributed containmentproblems for static leaders and time-varying leaders, and design containment protocols todrive all followers to the convex hull spanned by the leaders.(2) For the consensus problem of a class of multi-agent systems with unknownLipschitz nonlinear dynamics, external disturbances, and parameter uncertainties under afixed directed graph, we design a kind of output H distributed consensus protocols, andgive the sufficient condition that the proposed protocol gurtantees the multi-agent systemsto achieve consensus.(3) For the distributed leadless consensus problem for multiple quadrotor systemsunder fixed and switching topologies, we design the protocols to achieve the consensus forthe networked quadrotors positions and attitudes via feedback linearization and robustcontrol theory.(4) For the multiple quadrotors under fixed directed topology, from the consensusresults of multi-agent systems, we propose two distributed sliding-mode protocols to dealwith the cases of the leadless consensus problem and the tracking consensus problem.(5) For the multiple quadrotors with input saturations, we investigate the distributedleaderless formation problem, and design the control protocol to make all quadrotors constitute the desired formation and compensate the effect of the saturations.(6) For the cooperative problem of multiple quadrotors, under the fixed directedtopology having a spanning tree, we design the distributed leadless/tracking protocols viaDynamic Surface Control (DSC). These protocols make multiple quadrotors finishcooperative missions.