On maintaining visibility in multi-robot-networks with limited field-of-view sensors

A multi-robot team can be endowed with a sensing graph whose edges indicate when one robot is visible to another. Visibility enables the robots to measure each others' relative position. The performance of different multi-robot coordination algorithms are therefore dependent on the connectivity properties of the sensing graph. Many coordination methods assume that the sensing graph is undirected. When the robots are equipped with limited field-of-view sensors, the sensing graph becomes directed. This paper provides a control algorithm to maintain the strong connectivity of a directed sensing graph in the presence of bounded persistent disturbances.