Dynamic Positioning of Underactuated AUVs Using Visual Servoing

The problem of the autonomous underwater vehicles (AUVs) dynamic positioning (DP) in the horizontal plane (HP) using a monocular video camera is considered. A AUV control is formed from the incoming information about the centroid position of a given object or the centroid of key bottom points. It is assumed that the underactuated AUV can move in the HP under the impact of thrust force and turning moment. A constant underwater current is considered as a perturbing influence. The control system is designed on the basis of image based visual servoing approach relying on the methods of stability theory. Algorithms for controlling the AUV DP in the vicinity of a given point above the seabed which do not require estimation of the direction and velocity of the current are proposed. The results are illustrated by computer modelling.