Development and evaluation of operator support system for rotary crane

Rotary cranes are widely used for the transfer and discharge of loads at harbors, building sites, and factories. These tasks involve many problems such as load sway, positioning, and obstacle avoidance. Therefore, the development of a control system to support the operator is strongly demanded. The purpose of this paper is to develop an operator support system focusing on obstacle avoidance and sway suppression. Information of danger is transmitted to an operator by haptic control. In order to suppress load sway, the Hybrid Shape Approach was applied and a potential field was derived by an equation of diffusion at cylindrical polar coordinates; this in turn was used to construct an algorithm of crane velocity restriction for haptic feedback. The effectiveness of the proposed system was demonstrated by simulations and experiments.