2002 Volume 2002 Issue 5-2 Pages 591-596
The iterative learning control (ILC) learns the unknown information from repeated control operations. The tracking error from previous stages is used as the correction factor for the next control action. Therefore, the ILC controller can make the system tracking error converge. to a small region within the limited numbers of iterations. In this paper, a proportional-valve controlled hydraulic cylinder system with repeated external loads is built to perform the position tracking control experiments. The PID and ILC controllers are implemented in these experiments and the results are compared. We use the P-type update law with delay parameter for its position tracking control. Experimental results show that the ILC controller can effectively control the system to track the repetitive position trajectory, especially in transient response that traditional control methods can't follow appropriately. Therefore, in this application, the control performance of the ILC is superior to the traditional PID controller.