Abstract
Overhead cranes are widely used and play a significant role for mass transportation in factories. One of the main problems in operating an overhead crane is the residual vibration which often decreases efficiency and safety of the operation. In order to deal with this problem, the authors proposed a new type of open-loop control method for suppressing the residual vibration by eliminating natural frequency component. This method is based on the fact that residual vibration is completely suppressed in a linear undamped system excited by an external force that does not contain the natural frequency component of the system. The authors have applied this property to a nonlinear damped system and developed an efficient method to derive an adequate trajectory of the trolley of the overhead crane which enables complete prevention of the residual vibration of the cargo. This paper proposes a systematic method for designing path of the trolley whereby the trolley and the cargo are both able to avoid obstacles while minimizing the path as well as keeping the residual vibration suppressed. The effectiveness of the proposed method is examined by numerical simulations.
