Stable repetitive control by frequency aliasing
نویسندگان
چکیده
A filtering technique based on frequency aliasing which was initially developed for Iterative Learning Control is modified so that it can be implemented in real-time and is suitable for Repetitive Control. The aliasing technique is experimentally verified on a gantry robot facility, which manipulates payloads from a dispenser onto a constant velocity conveyor. A parallel arrangement consisting of a three-term feedback controller and a simple structure repetitive controller is used to control the robot. Without the aliasing technique, the combined control system becomes unstable very rapidly. In contrast, when the aliasing technique is applied, 1000 repetitions are successfully completed and no indications of impending instability can be seen.
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