Google alert set to "virtual leader" brings us to this abstract:
Without assuming that the interaction diagraph is strongly connected or contains a directed spanning tree, this paper studies the second-order leader-following consensus problem of nonlinear multi-agent systems with general network topologies. Based on graph theory, matrix theory, and LaSalle’s invariance principle, a pinning control algorithm is proposed to achieve leader-following consensus in a network of agents with nonlinear second-order dynamics. Furthermore, a pinning consensus protocol is developed for coupled double-integrators with a constant reference velocity. In particular, this paper addresses what kind of agents and how many agents should be pinned, and establishes some sufficient conditions to guarantee that all agents asymptotically follow the virtual leader. Numerical simulations are given to verify the theoretical analysis.
I think it says that everyone follows the leader, which I believe we learned in first grade. But without the numerical simulations. Here's the citation for what is certainly a brilliant paper (no offense, authors of "Second-order leader-following consensus of nonlinear multi-agent systems via pinning control").