Sway Reduction on Container Cranes Using Delayed Feedback Controller: Simulations and Experiments

Traditionally, container cranes are modeled as a simple pendulum with a lumped mass at the end of a cable. In the case of large container cranes, the actual configuration of the hoisting mechanism is significantly different; it consists typically of a set of four hoisting cables. These cables are hoisted from four different points on the trolley and are attached on the load side to four points on a spreader bar used to lift containers. The dynamics of the actual hoisting assembly of a container crane is different from that of a simple pendulum. A controller design based on the actual model will more likely result in a response superior to those based on simple models. In this work, a nonlinear mathematical model of the actual container crane is developed. A delayed position-feedback controller is designed. Performance of the controller is simulated on a 1/10 scale model of a 65-ton container crane using the full nonlinear model. Simulation results are verified experimentally on a 1/10 scale model of the same container crane.