Brake disc is an important component in a car's braking system, mainly used to provide friction to slow or stop the vehicle as it rotates. In order to increase production capacity, the customer invested in a new factory and added an automated unmanned machine plus production line. Brake discs are usually delivered in frames and placed by forklift trucks. The workpieces are stacked on top of each other in the frames, which presents a disordered state, and there may also be some special postures during the gripping process that cause gripping difficulties. The introduction of 3D vision system, through scanning, judgement, guide the robot in accordance with a reasonable strategy to grasp the pieces of material layer by layer, the vision software can also be robot obstacle avoidance judgement, to ensure that the middle and lower layers and the edge of the workpiece safety gripping.