Date of Award
Forging, Materials handling -- Control systems, Metallurgy
"Pick and place" robotic material handling has been a key to increase piece rates and reduced variability in forging processes. One of the drawbacks to current "pick and place" robotic material handling methods is the inability to locate the part after a forging operation and move it to the next position in a timely manner. If the billet changes position during the forging process, the manipulator will take longer to find the part and transfer it to the next station or the manipulator will be unable to move the part to the next position correctly which may cause scrap. Another drawback is due to the fact that the robot must let go of the billet and move out of the way of the equipment so to not get damaged. This adds extra time to the cycle and reduces productivity. By using sliding mode controls the robotic manipulator will be able to maintain hold of the billet during forging process and rapidly move the part to the next operation. This reduces handling time and possible scrap. The sliding mode controller will be designed to regulate the center position of the billet and the impedance of the gripper. Impedance is the way that a controller can control the force developed in a system. By controlling the impedance of the gripper, the forces on the outside of the billet will be maintained at a level that prevents the billet and the gripper from being destroyed. A mock forging operation was setup and tested to show how the system would work with a simplified gripper
Stake, Derek, "Hybrid Position and Impedance Control of a Forging Process" (2013). ETD Archive. 648.