Comparative Study on Speed Control Strategy of Stacker Crane

In this paper, the existing control methods of multi-stage speed regulation, speed closed-loop, and displacement closed-loop for the automated three-dimensional warehouse stackers are analyzed. It is found that the multi-stage speed regulation control method has problems such as too large column amplitude, easy speed mutation, and long operating time; and the single speed closed-loop control system needs to run a distance at a low speed to reduce the operation efficiency. Although the displacement embedded speed closed-loop control system has accurate positioning and fast dynamic response, the sudden change of speed can easily lead to the accident of cargo collapse. In view of the above problems, the S-shaped speed curve control method is proposed to improve the speed, safety and positioning accuracy of the stacker. Then, the second order simulation model of column swing is established in the Matlab/Simulink module. Compared with the simulation, the speed is reduced by 7.6% and the amplitude is reduced by 8.3%, so this method has better rapidity, stationarity and positioning accuracy, especially in medium and long distance.