Load-position control of overhead travelling crane in terms of fixed-pole approach for 3-D transfer path

This paper presents modeling and control of an overhead traveling crane in a three dimensional(3-D) complex transfer path. A mathematical model of 3-D overhead crane is newly built. It is proposed to feedback a load-position instead of conventional cart-position, in order to evade the collision of load with obstacles and achieve the reduction of both transfer time and residual vibration. In oder to keep control quality against the change of rope length, a variable gain controller using a fixed-pole approach is independently applied in X- and Y- directions.