UAV reference conditioning for formation control via set invariance and sliding modes*

A novel methodology is proposed for formation control of UAVs. The scheme is based on the sliding mode reference conditioning technique in a sort of supervisory level. The main idea is to shape the UAVs references in order to keep them coordinated. This implies a virtual leader which has the information of the formation structure, position of the agents in the formation and bounds on the distance between its reference and the ones of the agents. Geometric set invariance techniques together with sliding mode control is used for this purpose in order to make some set, defined from the reference constraints, invariant. To show the applicability of the approach, the problem of coordination and formation a number UAVs in cartesian motion is illustrated through simulation results using non-linear identified models of the UAVs.