All masses and geomtry are preset as reported in the paper
The motor amplitudes are preset as reported in the paper
The motor frequencies are preset as reported in the paper
One can turn on or off the motors and damping.
The crane can be placed in different possitions by using the sliders.
Notice that the motor behaves sinusoidally. After one full cycle, the motor switches sign to bring the device back to original position.
Viscous damping is preset as reported, and can only be turned on or off
Abstract
A decline in oil-related revenues challenges Norway to adopt emerging technologies. Thus, there is a renewed focus on the marine industry and its challenges in terms of new types of offshore installations and their maintenance.
This project analyzes the motion of a ship induced by an onboard crane in operation. Often, ship-mounted crane systems transfer cargo or crew onto marine structures such as floating windmills.
This research analyzes the motion of a crane mounted on a ship using The Moving Frame Method (MFM). The MFM draws upon Lie group theory and Cartan’s Moving Frames. This, together with a compact notation from geometrical physics, makes it possible to extract the equations of motion, expeditiously.
This work extends a previous project that assumed many simplifications. This current work accounts for the masses and geometry of all components. This current approach also prepares for buoyancy forces and accounts interactive motor couples.
The previous work used a symbolic manipulator, resulting in unwieldy equations. In this current extension, this research solves the equations numerically using a relatively simple numerical integration scheme. Then, the Cayley-Hamilton theorem and Rodriguez’s formula reconstructs the rotation matrix for the ship.
Furthermore, this work displays the rotating ship in 3D, viewable on mobile devices. WebGL is a JavaScript API for rendering interactive 3D and 2D graphics within any compatible web browser without the use of plug-ins. This paper presents the results qualitatively as a 3D simulation and suggests that “smart ships,” is the next step in this work.