Co-Ordinated Rendezvous of Unmanned Air Vehicles to a Formation Using a Sliding Mode Approach

Abstract

A method for the co-ordinated rendezvous of a team of unmanned air vehicles (UAVs) to a formation through the use of sliding mode control is presented. The focus of this work is on the scenario where three ‘follower’ UAVs must rendezvous in a desired formation about a ‘Leader’ UAV in a finite time. An assumption is made that each UAV only receives knowledge of the bounds of the manoeuvres that the other UAVs are performing. By not requiring manoeuvre information to be constantly available, a level of robustness to possible communication outages between UAVs is obtained. The proposed method also guarantees that the formation will be achieved in a finite time through the use of a concept of sliding mode terminal guidance (SMTG). SMTG takes advantage of the finite-time reaching phase of sliding mode to ensure that any desired constraint can be fulfilled in a finite time.