Mixed self/event-triggered ternary control for resilient consensus against mobile adversarial agents

In this paper, we consider the problem of multi-agent consensus in the presence of mobile adversaries. Faulty agents try to prevent the coordination among the regular agents and moreover are mobile in the sense that they can change their identities over time. Our approach towards resilient consensus is to extend the so-called mean subsequence reduced (MSR) algorithms to reduce the necessary communication based on three measures: (i) The information exchanged by the agents takes the form of ternary data in each message. (ii) A self-triggered method is first used so that agents avoid overreacting to DoS type attacks and maintain a certain communication rate. (iii) To enable the transmissions to terminate after reaching consensus, an event-triggered method is further introduced into the algorithm, resulting in a mixed protocol. Our study reveals that certain new features introduced in the protocols as well as in the conditions on network structures are critical to cope with potential attack strategies enabled by the mobile nature of the adversarial agents under ternary control. We verify the effectiveness of the proposed algorithm by means of a numerical example.