Washing machine counterweights are made of cement, which is heavy and time-consuming to load manually, and according to different production plans, it is necessary to load multi-specification counterweights at the same station in batches, so the customer urgently needs to upgrade the automation of the production line. By using a 3D vision system to guide the robot to complete the handling and depalletizing, and realising the feeding of multi-specification counterweights at the same station by fast template switching, the production efficiency of the assembly line is ensured, the utilisation rate of the production line equipment is improved, and the production cost is reduced.