Iterative motion feedforward tuning: A data-driven approach based on instrumental variable identification. (April 2015)

• Record Type: Journal Article
• Authors: Boeren, Frank; Oomen, Tom; Steinbuch, Maarten
• Is Part Of: Control engineering practice. Volume 37(2015)
• Page Start: 11
• Page End: 19
• Publication Date: 2015-04
• Subjects: Feedforward Control -- Iterative learning control -- Data-driven control -- Precision motion systems -- System identification; Automatic control -- Periodicals; 629.89
• DOI: 10.1016/j.conengprac.2014.12.015
• Languages: English
• ISSNs: 0967-0661

Abstract

Abstract: Feedforward control can significantly enhance the performance of motion systems through compensation of known disturbances. This paper aims to develop a new procedure to tune a feedforward controller based on measured data obtained in finite time tasks. Hereto, a suitable feedforward parametrization is introduced that provides good extrapolation properties for a class of reference signals. Next, connections with closed-loop system identification are established. In particular, instrumental variables, which have been proven very useful in closed-loop system identification, are selected to tune the feedforward controller. These instrumental variables closely resemble traditional engineering tuning practice. In contrast to pre-existing approaches, the feedforward controller can be updated after each task, irrespective of noise acting on the system. Experimental results confirm the practical relevance of the proposed method.