Abstract
In travelling crane systems, the load-swing sometimes has an oscillation component perpendicular to a travelling direction by accidental disturbances. This paper analyzes the dynamics of the load swing with the rope length as another control channel to the crane system and proposes a control strategy both to suppress the load swing and to control the trolley position. In the control, the rope length is variated to move the load upwards and downwards following to a sinusoidal function so that the swing direction of the load rotates. At the same time, the trolley is controlled to eliminate the oscillation component of the load growing in its travelling direction and to approach to a desired position of the trolley. The control is evaluated by numerical experiments and proved to be effective.
