  This paper considers the distributed consensus problems for multi-agent
systems with general linear and Lipschitz nonlinear dynamics. Distributed
relative-state consensus protocols with an adaptive law for adjusting the
coupling weights between neighboring agents are designed for both the linear
and nonlinear cases, under which consensus is reached for all undirected
connected communication graphs. Extensions to the case with a leader-follower
communication graph are further studied. In contrast to the existing results in
the literature, the adaptive consensus protocols here can be implemented by
each agent in a fully distributed fashion without using any global information.
