Event Triggered Distributed Collaborative Control
Date: August 23 - August 26, 2009
We consider the collaborative control of a group of autonomous mobile agents (e.g. vehicles, robots). The agents collaborate to achieve a common goal or objective, like to move in a particular area and cover it, while avoiding obstacles and collisions. Building upon our earlier work on deterministic, randomized and hybrid distributed coordination algorithms we consider the communication needs of the agents, and in particular, the connectivity of their communication network as they move. We develop algorithms that automatically sense the possibility or inset of loss of connectivity among the agents. We also consider the automatic detection of path disconnection when more than one paths need to be maintained between pairs of agents. Using local probing schemes we formulate such problems as event-triggered control problems. We develop distributed algorithms that automatically select some agents and move them appropriately so as to maintain a certain degree of desired connectivity among the moving agents. We characterize the trade-off between the gain from maintaining a certain degree of connectivity vs the combined cost of communications and the associated dynamic re-positioning of agents. The results illustrate the efficiency achieved by the event-triggered control in such problems. We also describe the resulting communication topologies and in particular their similarity to dynamic small-world topologies.