Automatic berthing control under wind disturbances and its implementation in an embedded system

• Published in: Journal of marine science and technology Vol. 28; no. 2; pp. 452 - 470
• Main Authors: Sawada, Ryohei, Hirata, Koichi, Kitagawa, Yasushi
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Japan 01.06.2023; Springer; Springer Nature B.V
• Subjects: Algorithms; Automatic control; Automation; Automotive Engineering; Berthing; Communication; Control algorithms; Control theory; Controllers; Disturbances; Embedded systems; Engineering; Engineering Design; Engineering Fluid Dynamics; Experiments; Feedforward control; Mechanical Engineering; Methods; Neural networks; Numerical analysis; Offshore Engineering; Original Article; Path planning; Personal computers; Programmable logic controllers; R&D; Research & development; Simulation methods; Task complexity; Trajectory planning; User interface; Wind; Wind effects; Japan; Operational design domain; Automatic berthing; Wind disturbance; Programmable logic controller; Autonomous ship
• ISSN: 0948-4280; 1437-8213
• DOI: 10.1007/s00773-023-00934-9

This paper proposes a practical algorithm and its implementation of automatic berthing in wind disturbances environments. Berthing operation is one of the most complex tasks for seafarers. Automation of the highly burdensome berthing maneuver can be used to assist seafarers. In this study, we analyze the effect of wind disturbance on path following and propose a new path following control algorithm using a 2-DoF controller that introduces a feed-forward control. We also propose a method to reduce path deviation by introducing a runway in path planning. The effectiveness of the proposed method is verified by numerical simulations and shipboard tests using an experimental ship, and the proposed method shows higher performance under wind disturbance than the previous methods. The algorithm verified in this study is implemented as a PLC system, AutoBerth PLC. A PLC is an industrial computer, stable in operation. Using the AutoBerth PLC, we conducted an experiment of automatic berthing by an actual ship and confirmed that the system can be controlled faster and more stable than when controlled by a laptop. To realize a practical system, an alert function for the ODD, an alert function for fallback response regarding self-diagnosis of PLCs and communication monitoring functions were implemented as required functions in a maritime autonomous surface ship (MASS), and these functions were verified on the experimental ship.