Cooperative location of multiple unmanned surface vessels( USVs) considering communication delay

Considering the positioning failure caused by the communication delay in cooperative location process of multiple unmanned surface vessels( USVs),this paper proposes a delay expanded Kalman filtering( DEKF) with state estimation error compensation,based on the observability analysis of the multi-vessel cooperative location system. First,the nonlinear equations of states and measurements of multi-vessel cooperative location based on one leader USV are established. Then,the observability conditions of the multi-vessel cooperative location system are given based on the nonlinear system observability criterion. Finally,a new filtering method is proposed in the presence of measurement delay,in which the measurements are predicted in advance to compensate the state estimation error. The simulation results show that this method can effectively compensate for positioning errors caused by communication delay in the cooperative location process,which is of great significance to the engineering practice.