Nonlinear Dynamics of Crane Operation at Sea

The work proposed is a feasibility study of novel control system concepts to improve the performance and safety of existing crane systems on crane ships transferring containerized cargo to lighters offshore in high sea states. Unique elements of this concept include novel effectors to produce precise, high bandwidth control forces. These effectors, coupled with appropriate sensors, would be used to implement a specially designed control system to reject disturbances from crane ship motion, damp pendulation of the load, track the lighter, and match the container motion to the lighter motion. In addition the control system will be specifically designed to meet manual control requirements of the crane operator and to provide options for further automation of cargo handling. The proposed work will address the influence of specific nonlinearities in the crane ship-crane-container-lighter multi-body dynamics and the influence of these nonlinearities on the control system design.