Article ID Journal Published Year Pages File Type
1720339 Applied Ocean Research 2011 12 Pages PDF
Abstract

Oil slick detection and guiding of oil recovery ship by using on board tethered UAV need a non-linear dynamic model for the aerial umbilical including variable length domain and material elasticity. Considering the flight phases constraints and the system definition, two continuous models are presented using a Lagrangian approach or an updated Lagrangian one, both including different kinds of boundary condition at the umbilical bottom end. At the winch position, during a take-off or landing (TOL) phase flight, a geometrical singularity occurs in the Lagrangian approach while in the updated Lagrangian one, a difference exists between the unstrained curvilinear coordinate velocity and the strained umbilical material point velocity. Properties of internal strain energy and non-linear strain measure permit to characterize the regularity of the longitudinal and transversal umbilical displacements. From the continuous models we deduce the discrete finite-element models. Numerical examples with until eleven nodes are given, including the case of an emergency flight phase. Applications of this captive aerial detection system are equally discussed.

Related Topics
Physical Sciences and Engineering Engineering Ocean Engineering
Authors
,