A Digital Version of the Adaptive Speed-Gradient-based Control for Complex Vehicle Dynamics
In this paper a digital adaptive algorithm for path tracking of underwater vehicles in many degrees of freedom (up to six) was presented. It is based on speed-gradient laws and sampled-data models constructed with Adams-Bashforth approximations. Here it is assumed that no knowledge is required of the matrices of the Coriolis and centripetal forces, buoyancy, linear and quadratic damping. An analysis of stability for the path tracking problem is presented in which an optimal and, alternatively, a suboptimal control action are employed. The features of the approach are illustrated by means of a numerically simulated case study of a 6-degrees-of-freedom underwater vehicle maneuvering in the water column and sea bottom.