Automatic hook crane with robotic arm

In sling work using a crane, workers near the hook sometimes have an accident. For example, accidents happen due to load shifting, and collision between the hook and the workers. In this study, we propose a new crane system with the hook moved by a robotic arm. When an operator brings the hook around a target object, the robotic arm hung from the end of the crane wire moves the hook to catch the object automatically. Then, it is unnecessary for workers to operate a hook precisely. We should pay attention that it is hard for a normal serial arm to reach off the place just below the wire because of its gravity center. It is necessary to analyze the structure of the arm that the hook can reach far position. In this report, the robotic arm with one driving joint and one passive joint is proposed for moving hook horizontally. Best parameter of the arm is discussed by the simulation. The prototype was made actually and it was confirmed that the prototype arm can move the hook as far as the simulation results.