Motion and Vibration Control for Suspended Stacker Crane Using Model Reference 2DOF

抄録

In general, a stacker crane in a large automatic warehouse is heavy. The weight reduction of large stacker cranes greatly contributes to the improvement of warehouse system capacity. In order to greatly reduce the weight, we devise a suspension crane with a traveling drive unit on top of the stacker crane. By using a hanging pin structure and Adopting a linear motor. On the other hand, the suspension pin structure is greatly shaken, and the linear motor has a large friction. As a result, the required propulsive force may not be obtained with respect to the commanded current, and positioning as a crane becomes difficult, and the load cannot be transferred to the rack due to shaking, which adversely affects the tact time. In this study, we will use a physical model that captures the characteristics of a suspended crane to realize traveling control that does not excite the crane swing. Specifically, a two-degree-of-freedom (2DOF) control that follows the reference model is constructed, and feed-forward input and position reference that do not excite shaking are given. In order to reduce the influence of large friction, the Kalman filter is used to estimate the external force and the speed and position of the drive unit, and to control the movement and vibration of the suspended crane. Its effectiveness is verified by simulation and experiment.