Abstract
A pipelaying control method is presented in this paper which includes path planning, path guidance, and path tracking controller for dynamically positioned (DP) surface vessels based on the characteristics of the predefined path in marine pipelaying operation. The pipelaying control method depends on path coding, path selection logic system, and a sliding matrix. The sliding matrix contains a vessel local path and its specified control requirements, which can be updated by sliding down the waypoint table line by line as the vessel is traveling from one path to the next. A line of sight (LOS) algorithm is developed to calculate the desired vessel position and heading on a circular arc path. The motion controller, which can simultaneously control the vessel speed at the directions of surge and sway, is designed by decomposing the desired inertial resulting velocity into the desired body velocity components. A DP simulator for pipelaying operation is developed, and in order to verify the proposed method, a pipelaying simulation is carried out. The simulation results show that the proposed method enables the vessel to move along the desired path while maintaining a set crab angle, a specified speed, and a turning radius. The pipeline can be laid onto the specified waypoints even when the vessel is subjected to drift forces caused by ocean currents, wind, and waves.
Highlights
Over the last two decades, deep-water pipelaying has gone through a spectacular development and the present methods and trends in deep-water pipelay systems are described in [1] by Fossen
In order to realize the design of continuous pipe laying method of rolling pipe laying method, it is necessary to take into account the characteristics of pipe laying operation and the research of ship path tracking control method and organically combine the two to realize this method
Through the operation simulation of pipelaying by dynamic positioning (DP) ship and the analysis of the simulation results of pipeline trajectory, ship trajectory, pipelaying accuracy, pipelaying speed, and heading angle, the following conclusions can be obtained: (1) A systematic method of pipelaying motion planning, guidance, and control of DP ship is proposed in this paper, which can control the pipelaying ship to switch smoothly between straight line and curve path, automatically update the path and relevant control information along the waypoint table, and realize the continuous laying of offshore pipeline at a specified speed
Summary
Over the last two decades, deep-water pipelaying has gone through a spectacular development and the present methods and trends in deep-water pipelay systems are described in [1] by Fossen. Fu et al [5, 13] developed a method of path analysis and mapping relation between the desired pipeline path and the desired vessel path and used sliding mode control to study the tracking control of pipe laying operation of pipelaying ship [14]. Nie and Lin [23] proposed an adaptive fuzzy path following control law, which is based on the improved adaptive integrated line of sight (IAILOS) guidance law for the control of underactuated ship in the case of time-varying ocean current and sideslip. A systematic method, including path planning, guidance algorithm, and path tracking for pipelaying vessels, is presented from the prospect of the whole DP control system. The effectiveness of the proposed control method of pipelaying control is verified using a DP simulator
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
