Cargo Pendulation Reduction on Ship-Mounted Cranes Via Boom-Luff Angle Actuation

The wave-induced motions of a ship can cause large pendulations of cargo being hoisted by a ship-mounted crane. In this paper, the authors show that controlling the boom-luff angle can reduce these pendulations significantly. A planar pendulum with a rigid massless cable and massive point load is used to model the system. A control law using delayed position feedback is developed, and the controlled system is simulated on a computer using the full nonlinear equations of motion. The computer simulation results are verified experimentally using a three-degree-of-freedom ship-motion simulation platform and a 1/24th scale model of a T-ACS crane.