Flocking of Cucker-Smale model with unit speed on general digraphs

In the literature, the study of the continuous Cucker-Smale flocking model with unit speed is all restricted to completed undirected graphs. In this paper, we consider the flocking of the Cucker-Smale model with unit speed constraint on general digraphs, which contain the completed undirected graphs as special cases. For this model, we prove that the flocking would occur under some conditions depending only on initial data. Finally, we provide several numerical simulations to illustrate the obtained results.