Dynamic positioning of an uninhabited surface vehicle using state-dependent Riccati equation and pseudospectral method

Abstract

This paper proposed a novel control method for dynamic positioning of an uninhabited surface vehicle (USV). A state-dependent Riccati equation (SDRE) technique was introduced to deal with dynamic positioning problem of the USV. A new state-dependent coefficient (SDC) matrix was built to show the relationship between variables and satisfy the control inputs saturation for practical application. In order to solve the SDRE in real time, a semi-analytical formulation was derived by using Legendre-Gauss-Radau pseudospectral method. Simulation results show that the proposed method can be applied in real time and the USV can maintain its position and heading accurately and remains stable.