Optimal trajectory tracking control of AUVs with delays in actuator and measurement under shallow wave disturbances

摘要

This paper considers the optimal trajectory tracking control (OTTC) problem for autonomous underwater vehicles (AUVs) with delays in actuator and measurement affected by shallow wave disturbances. Firstly, we construct the models of AUVs with delays, shallow wave disturbances and the desired trajectory respectively. Secondly, through a particular transformation, the original AUV system with delays is reduced into a non-delay free system. Then the coupled two-point boundary value (TPBV) problems are derived from the optimal control theory; and using a recently developed successive approximation approach to construct sequences, the coupled TPBV problem is transformed into two decoupled linear differential sequences in state vectors and adjoint vectors. By iterative solving the two differential sequences, the approximate OTTC law is obtained. Finally, the effectiveness and feasibility of the OTTC law is demonstrated by a dynamic model of the Remote Environmental Unit (REMUS) AUVs.