On the behavior of an underwater remotely operated vehicle in a uniform current

This paper presents a series of analyses on the behavior of an underwater remotely operated vehicle (ROV) with the umbilical cable in uniform current. The hydrodynamic mathematical model including the coupled effect of the current and the umbilical cable is proposed here to deal with 6 degrees of freedom motions of the ROV. Because of the umbilical cable on the ROV, the present problem is the two-point boundary value problem with respect to a set of first-order ordinary differential equation systems, which are solved by applying the multistep shooting method. The corresponding hydrodynamic coefficients of the underwater vehicle used in the hydrodynamic model are obtained by the planar motion mechanism (PMM) test technique. Three different current speeds are considered to investigate the current effect on the ROV's operations including forward motion, ascending motion, and descending motion. The present results reveal that the current indeed significantly affects the operations of the ROV, and the mathematical numerical model developed here can serve as a useful tool to offer some valuable information for the anticurrent ROV design.