Formation control for unmanned surface vessels : A game-theoretic approach

Two types of formation control problems for a group of unmanned surface vessels (USVs) are investigated by using a game-theoretic approach. In the two formation frameworks, the USVs have the group formation objective of minimizing the formation errors with their local neighbors. Different from the existing formation control schemes for USVs with only the group objective, the formation control framework in this paper takes into account the individual objectives of the USVs in addition to the collaborative formation requirement for the USVs. Specifically, each USV in the first formation framework has the individual objective of aiming to be located at a given static reference target according to its own interests. And the USVs in the second formation framework have the individual objectives of following a given time-varying reference target. Considering that the individual objectives of the USVs may conflict with the group formation objective, the formation problem of USVs is transformed to a noncooperative game among multiple USVs. Two controllers based on the Nash equilibrium seeking strategy are designed to solve the formation problem of USVs with conflicting objectives. It is proved that the USVs' states form an equilibrium formation pattern driven by the designed controllers. Simulations are performed to verify the theoretical results.