Optimizing tracking performance of XY repositioning system with ILC

Controlling complex mechanical systems is often a difficult task, requiring a skilled developer with experience in control engineering. In practice however, the theoretical difficulties of designing a good controller is only a first step as the implementation itself on the various pieces of equipment is also often challenging. This paper investigates if iterative learning control (ILC) can be used as an alternative to tuning existing controllers for improving system performance. This is evaluated by a case study on a high speed XY-positioning system used for laser cutting. An ILC algorithm is implemented by using a server client structure from Matlab. After tuning the parameters an implementation is found which is able to increase the tracking accuracy significantly for cutting speeds up to 0:5 m=s. This is done only by implementing code on the master control unit and thus without changing subsystem controllers.