Abstract
The main purpose of any crane system is to move a load to a specified place. Accurate load positioning in the presence of unpredictable external factors is an important issue when operating a crane. Attenuation of load vibration during crane operation is immensely critical in order to satisfy rigorous requirements for safety and efficiency. When a crane is installed and operated on a vessel at sea, work conditions become even more difficult and thus require more stringent attention to load positioning and attenuation of load vibration. At sea, this process is complicated due to factors such as waves and wind, making accurate crane operation nearly impossible. For these reasons, active heave compensation systems have been developed to suppress the effects of disturbances raised from the harsh sea environment including vessel motions. This paper explores the suppression method of unexpected vertical vibration of load. Unlike past research on the topic, this research includes rope dynamics in the control system design for suppressing load vibration. In addition, this research considers uncertain disturbances—vessel motions not controlled by any active force that result in undesirable heave motion of a crane. Load motion is indirectly estimated using a load cell because we do not yet have any useful tool to measure it directly. In the considered crane system, two winches were used, one for moving the load and the other for suppressing residual vibration. To evaluate the proposed control strategy and system performance, several control techniques were applied: proportional–integral–derivative control, sliding mode control, and feedback linearization control methods.
Highlights
For both offshore and onshore work environments, load moving is the main work of cranes
Because we do not have any useful method to suppress the heave motion of a vessel, our research focused on just the crane system
In terms of load motion control, we found that the measurement of load position and displacement was problematic, meaning that accurate load motion control in the real world is overly difficult
Summary
For both offshore and onshore work environments, load moving is the main work of cranes. The heaving motion typical of harsh sea conditions is a key issue for inspection, maintenance, and repair of equipment. In both the harbor area and shipbuilding industries, load moving work is frequently operated on both sea and land, compounding the variables under which cranes operate. Cranes operated in harbor areas are installed on barge ships that are controlled by tugboats, compounding the number of external factors affecting load stability. Drill ships use an active heave compensation method to simultaneously control vessel motion and payload. By employing a heave compensation method, both vessel motion and payload are controlled, creating a safer and better operating performance for the payload system.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
