Dynamic damping of payload motion for cranes

The paper describes a novel strategy for damping of payload motion for various kinds of cranes used in construction, i.e., mobile cranes, boom or tower cranes and so forth, which can be implemented on existing equipment. Most research in this area concentrates on controlling the velocity and accelerations to eliminate inertial forces. However, it is almost impossible to realistically model the effects of wind, slippage of tires, or settlement of supports, etc. The research proposes an approach to control the swaying of the payload, regardless of the cause. The control strategy is based on applying periodic balancing forces and moments to the cable to damp out oscillations as and when detected. A feedback control system applied to the cable has the potential of providing an inexpensive and easily implemented solution. This is achieved by decoupling the payload and cable system from the structural members of the crane during the development of the control strategy. Effective control of the payload will improve safety, productivity and timeliness for a number of material handling operations.