This paper deals with the control of a fleet of nonlinear systems representing AUVs (autonomous underwater vehicles). The purpose is here to design a control law to stabilize the fleet to time-varying formations which are not only circular. A novel framework is proposed to express a general control law for a large class of formations. This is produced by applying a sequence of affine transformations such as translations, rotations and scalings. The paper also includes a cooperative control to distribute the agents along the formation which takes into account the communication constraints. The system was implemented in computer simulation, accessible through Web.