  In this paper, we investigate the controllability of a class of formation
control systems. Given a directed graph, we assign an agent to each of its
vertices and let the edges of the graph describe the information flow in the
system. We relate the strongly connected components of this graph to the
reachable set of the formation control system. Moreover, we show that the
formation control model is approximately path-controllable over a
path-connected, open dense subset as long as the graph is weakly connected and
satisfies some mild assumption on the numbers of vertices of the strongly
connected components.
