Robust Nash equilibrium seeking based on semi-Markov switching topologies

Abstract: This paper investigates a distributed robust Nash Equilibrium (NE) seeking problem in fluctuating environments. Specifically, the players, subject to the second-order dynamics, are considered to be influenced by external disturbances and uncertain dynamics while communicating via semi-Markov switching topologies. In such constantly changing network circumstances, the existence of disturbances and uncertain dynamics may directly affect the performance of most existing NE seeking algorithms. Moreover, the semi-Markov switching topologies may cause communication uncertainty, which are considered in NE seeking for the first time. To accommodate the above concerns, the following targets require to be reached simultaneously: (1) Disturbances and uncertain dynamics rejection in finite time; (2) Distributed estimation on unknown information required for players' cost functions; (3) A reasonable estimation consensus protocol under semi-Markov switching; (4) NE seeking for the second-order players. By combining supertwisting-based Integral Sliding-Mode Control (ISMC) with average consensus tracking, a novel robust NE seeking algorithm is constructed, incorporating an effective leader-follower consensus protocol. Furthermore, to lessen dispensable information transmission, a sampled-data-based event-triggered mechanism is introduced. Incorporating the advantages of both semi-Markov switching and event-triggered mechanism, another NE seeking algorithm is proposed. Through designing an appropriate Lyapunov-Krasovskii functional, it is shown that the leader-follower consensus can be achieved in the mean-square sense under event-triggered mechanism. Finally, a connectivity control game is formulated to illustrate the validity of the designed algorithms.