A virtual environment for ship-mounted cranes

The authors present a virtual simulation of ships and ship-mounted cranes. The simulation is carried out in a Cave Automated Virtual Environment (CAVE). This simulation serves as a training platform for ship-mounted crane operators and as a platform to study the dynamics of ships and ship-mounted cranes under dynamic sea environments. A model of the (Auxiliary Crane Ship) T-ACS 4-6 was built, converted into an OpenGL C++ API, and then ported into the CAVE using DiverseGL (DGL). A six-degrees-of-freedom motion base was used to simulate the actual motion of the ship. The equations of motion of the ship are solved using the Large Amplitude Motion Program (LAMP), and the equations of motion of the crane payload are numerically integrated; the interaction between the payload and the ship is taken into consideration. A nonlinear delayed-position feedback-control system is applied to the crane, and the resulting simulation is used to compare the controlled and uncontrolled pendulations of the cargo. Our Simulator shows a great deal of realism and was used to simulate different ship-motion and cargo transfer scenarios.