Synchronized cross coupled sliding mode controllers for cooperative UAVs with communication delays

This paper deals with formation control of UAVs using a virtual structure. A synchronization strategy is proposed to synchronize the errors of a virtual leader position and attitude tracking by using sliding mode control. The synchronization is based on cross coupling of sliding mode controllers in a general communication topology, and the stability of the proposed strategy is studied in the presence of constant communication delays. Also, it is shown that the proposed approach can tolerate the effects of faulty UAVs in the formation. To verify the accuracy of the proposed strategy, numerical simulations are presented for a team of five UAVs making a pentagon formation.