Distributed average consensus control in networks of agents using outdated states

Time delays are commonly considered as a negative factor in the literature on consensus problems of multi-agent systems. This, however, is not always the fact. Here, the authors propose some consensus protocols for multi-agent systems with a fixed undirected communication topology. Different from the common consensus protocols for multi-agent systems, which uses the current states only, the protocols proposed here use both current states and outdated states. It is shown that the use of the outdated information can accelerate the consensus if the consensus protocols are chosen properly. Simulation examples are given to illustrate the effectiveness of the proposed algorithms.