Determination of the hydrodynamic parameters of an underwater vehicle during small scale, nonuniform, 1-dimensional translation

The hover and tight maneuvering regime of an underwater vehicle is difficult to characterize hydrodynamically. Characterization in a reliable model is necessary for successful control of the vehicle during task performance. A 1-dimensional system identification procedure for this regime is described. The experimental set up is simple and noncritical. The analysis is performed by minimizing the error between the trajectories of the vehicle and several numerical models during a free decay. Minimization is controlled by the Nelder-Meade simplex algorithm. Agreement with the work of other researchers is strong. The procedure is flexible and may be extended to coupled models with 4 degrees of freedom