Semi-Decentralized Optimal Control Technique for a Leader-Follower Team of Unmanned Systems with Partial Availability of the Leader Command

The main goal of this work is to design a controller for a team of unmanned vehicles that can accomplish a cohesive motion in a modified leader-follower structure. The desired output (command) is available for only the leader and the followers are communicating to the leader and among themselves in a ring topology. This team would be able to move together with a consensus on the desired output or leader command. A semi-decentralized optimal control strategy is designed based on minimization of a cost function defined for the group using local information. The interaction between vehicles due to information exchange is modelled in the characterization of the dynamical model of each vehicle and for this purpose the control input is divided into two parts, local and global control. Through incorporating interaction terms in the model of the team, a semi-decentralized control based on the available information is designed. The minimization of the proposed cost function results in a modified consensus algorithm for a leader-follower structure while the leader command is available partially. Finally, the simulation results are presented to show the effectiveness of our proposed method in achieving predefined requirements and goals.