  A wide range of applications require or can benefit from collaborative
behavior of a group of agents. The technical challenge addressed in this
chapter is the development of a decentralized control strategy that enables
each agent to independently navigate to ensure agents achieve a collective goal
while maintaining network connectivity. Specifically, cooperative controllers
are developed for networked agents with limited sensing and network
connectivity constraints. By modeling the interaction among the agents as a
graph, several different approaches to address the problems of preserving
network connectivity are presented, with the focus on a method that utilizes
navigation function frameworks. By modeling network connectivity constraints as
artificial obstacles in navigation functions, a decentralized control strategy
is presented in two particular applications, formation control and rendezvous
for a system of autonomous agents, which ensures global convergence to the
unique minimum of the potential field (i.e., desired formation or desired
destination) while preserving network connectivity. Simulation results are
provided to demonstrate the developed strategy.
