Abstract
This paper considers a control of travelling cranes which dissipates the physical energy of the oscillating load and drive the trolley to a desired position. The dynamics of the system is modelled by using Hamilton's-equations to describe the energy change of the system and to derive an energy dissipative feedback control law. The obtained control needs neither feedback of the swing angle of the load nor that of its time derivative. For the transportations of the load with heavy weight, the control shows high performance even under large changes of the rope length without using any information of the load-swing. On the other hand, the oscillation suppression effect degrades for the case of light load transportations. To avoid the degradation, we propose an improved partial state feedback control to follow the state trajectories of the closed loop system with heavy load. The validity of these two controls were verified by experiments on a model crane.
