Modelling of a captive unmanned aerial system teledetecting oil pollution on sea surface

TL;DR

This paper develops a finite-element model for a captive UAV system with an umbilical cable to detect oil spills on the sea surface, focusing on cable elasticity during take-off, landing, and flight phases.

Contribution

It introduces a time-dependent finite-element formulation for elastic cable modeling in UAV systems, including boundary conditions and validation methods.

Findings

Validated the model with exact solutions and numerical examples.

Analyzed the impact of wind on system equilibrium prediction.

Enhanced understanding of cable dynamics during UAV operations.

Abstract

Recent major oil-spills were tracked using observations with sufficient altitudes over the sea surface, to detect oil slick locations. For oil-spill responders, we propose a captive Unmanned Aerial System, UAS acting like a periscope over a ship or supply vessel. The system is composed of an umbilical deployed from ship deck, and there are few studies that have examined elasticity within cable dynamic during take-off or landing (TOL) and normal flight phases. Therefore, the safest approach for the control-commands of the system is through umbilical dynamic modelling. We give a time-dependant finite-element formulation, using improved elastic non-linear cable elements. Two kinds of boundary condition, natural or essential, are discussed for roll-in or roll-out of the umbilical. A numerical convergence and a validation with an exact solution are provided, using two examples for the flight parameters. Finally, sensitivity of the model potentially extends its capacity for the system equilibrium prediction, under wind primary influence.