Intelligent Positioning of Mobile Cranes for Steel Erection

The crane is the single most important equipment cost item required for erecting structural steel. Each time the crane moves to a new location, equipment time and labor time is lost. This research presents a computerized analysis method to minimize the number of moves required by a mobile crane to erect single story steel structures. The production rule system finds the optimum path for the crane and determines the steel erection sequence. Artificial intelligence techniques are employed to develop the production rule system. They system finds the optimum path for the crane and determines the steel erection sequence. The production rule system consists of three basic components. The first is a knowledge representation which describes the building and crane geometry. Second is the production rules for positioning the crane and sequencing the steel erection. These rules were structured from interviews with steel erectors and converted to logic based rules used in the program. Third is the control strategy which analyzes the various combinations of crane positions. The result is a microcomputer based Prolog program called PRECISE. This program finds the optimal crane positions and the structural members erected from each crane position.