Active Control of Crane-Load Vibrations on Ship Vessels

Abstract

In order to suppress crane load vibrations on ship vessels, a novel mechanism called a mechanical filter was developed by us recently. This mechanism was implemented on the basis of the premise that by actively and passively controlling the pivot point about which the load oscillates, one can effectively suppress crane load motions. In the present efforts, it is demonstrated that with an aid of a static feedback control law, one can effectively eliminate bifurcations that can lead to large changes in the crane load motions from the window of the considered ranges of disturbance frequency and disturbance amplitude parameters. The response amplitude of the crane load to ship-roll motions is attenuated to a low magnitude over the disturbance parameter window. Variations in the control input with respect to the crane-load mass are also investigated.