On the use of integral control actions for autonomous underwater vehicles

The use of integral or adaptive actions for the control problem of Autonomous Underwater Vehicles (AUVs) and Remotely Operated Vehicles (ROVs) is discussed in this paper. Generally speaking, the control laws are designed with respect to a mathematical model expressed either in the earth-fixed frame or in the vehicle-fixed frame. These two approaches, however, do not take into account the different origin of the effects that can affect the steady state errors: namely, the restoring generalized forces and the ocean current. With the use of a suitable adaptive action those effects can be properly taken into account as will be theoretically demonstrated in this paper.