Control of power-assisted crane system using direct manual manipulation

A power-assisted crane system is proposed. The purpose of this research is to develop a crane system which reduces the operator's burden by power assist and facilitates the intuitive operation of a heavy object by direct manual manipulation. First, the structure of this system and the control strategy are described, which consists of control of the velocity in proportion to the imposed force. Second, an analytical controller is designed to stabilize the system in spite of the uncertain resonance of the crane and to optimize response, i.e., to minimize the error from imposed force to velocity. Moreover, it is compared with the controller designed by linear matrix inequality (LMI) having the same optimality and robust stability. Finally, the effectiveness of this system is demonstrated by experiments.