Dynamics Analysis and Nonlinear Control of an Offshore Boom Crane

Abstract

This paper analyzes the dynamics of an offshore boom crane and proposes a high-performance nonlinear controller to drive the system states to track some constructed trajectories. Specifically, by employing Lagrange's method in an attached frame, a dynamic model is obtained for the offshore crane system consisting of the boom and a payload, with specific emphasis on the effect of the vessel's motion on the payload swing. Based on the model, a novel nonlinear control law is designed for the underactuated boom crane, which makes the system states track some planned trajectories successfully, even in the presence of persistent disturbance in harsh sea conditions. The stability of the designed closed-loop system is proven by Lyapunov techniques. Simulation and experimental results are included to demonstrate that the proposed control method significantly reduces the impact of the disturbance in harsh sea conditions.

The Speed Control of Constant Tension Motor of Marine Crane

“…The stress and strain of anti-swing arm need to be analyzed, we can get the displacement and the stiffness equation [9,10]:…”

Three-axis Motion Compensated Crane Head Control**This work has been carried out at the Centre for Autonomous Marine Operations and Systems (NTNU AMOS). The Norwegian Research Council is acknowledged as the main sponsor of NTNU AMOS. This work was supported by Ulstein Power & Control AS and the Research Council of Norway, Project number 241205.

“…Examples of such operations are surface crane operations for installing equipment on the seafloor, launching and retrieving systems (LARS) and delivering supplies from vessels to platforms. Motion compensation in such systems are generally limited to one axis, i.e the vertical heave motion, (Fang et al, 2014;Küchler et al, 2011;Messineo and Serrano, 2009;Johansen et al, 2003). This paper considers the development of a crane head control designed for motion compensation in all three axes.…”

Effect of Operation Environmental Uncertainties on Cargo Sway Characteristics of Tower Cranes

“…And the uncertainties of the operation environment are a main factor to hinder the crane automation. If we neglect the influence factors, then we also neglect the dynamic characteristics of the real systems, so that the high precision tracking control algorithm is difficult to achieve [1][2][3][4][5] .…”