Although underwater vehicles often operate in time-varying, nonuniform currents, the effect of flow gradients on vehicle dynamics is typically ignored in motion models used for control and estimation. Forces and moments due to a nonuniform flow field are strongest when apparent mass effects are important and flight paths are most sensitive to these disturbances when flow-relative velocities are small – precisely the situation for underwater gliders. This paper presents a nonlinear multi-body dynamic model for an underwater glider operating in an unsteady, nonuniform flow. The eight degree of freedom model incorporates a cylindrically actuated moving mass, a common glider actuation scheme. To illustrate the utility of this full dynamic model, numerical motion predictions are compared with those of simpler models for a variety of nonuniform flow fields. We also demonstrate the use of the full dynamic model for flow estimation using parameter adaptive filtering.
Dynamics of underwater gliders in currents
Dynamik von Unterwasser-Gleitbooten in Strömungen
Ocean Engineering ; 84 ; 249-258
2014
10 Seiten, 26 Quellen
Article (Journal)
English