Fixed time output feedback containment for uncertain nonlinear multiagent systems with switching communication topologies.

This paper presents a fixed time containment protocol within output feedback framework for uncertain nonlinear multiagent systems (MASs) exposed to unknown leader dynamics under switching communication topologies. To characterize dynamic communication links among agents in uncertain environments, a Markov jumping process with partially known transition probability is introduced to circumvent the difficulties of requiring the exact elements of transition rates as a prior. Then, in order to eliminate the necessity of broadcasting local velocity states between neighboring agents over the wireless and reject the comprehensive uncertainties including unknown model nonlinearities, external disturbances as well as switching topology jumps, a fixed time extended state observer (FTESO) only using the relative position information as input data is established for follower agents to achieve a uniform fast and precise estimation capability. A fixed time output feedback containment protocol by means of observer is presented to ensure that individual follower is guided into the geometric area constituted by a fleet of unknown leaders with a consistent convergence time irrelevant of initial conditions. The outstanding features of the developed algorithm are threefold: First, a prescribed fixed time containment consensus with reduced communication burden and enhanced robustness can be implemented. Second, a Markov jumping process with a partially known transition probability is considered to stimulate switching communication topologies. Third, a FTESO is constructed for each agent to realize a fixed-time estimation without requiring accurate modeling information. Finally, the fixed time stabilization of cascaded system is illuminated by applying the Lyapunov-based methods and bi-limit homogeneity. Simulation examples validate the feasibility and strengths of developed control protocol.