Title: A gradient-based method to guard against system degradation in robust parameter design

Authors: Bernard Jacob Loeffelholz; Kenneth W. Bauer

Addresses: Sensors Directorate, Air Force Research Laboratory (AFRL), WPAFB, OH 45433-7765, USA. ' Department of Operational Sciences, Air Force Institute of Technology, WPAFB, OH 45433-7765, USA

Abstract: Robust parameter design (RPD) can be implemented in systems in which a user, through the setting of the levels of controllable factors, seeks to minimise the variability of a system response influenced by uncontrollable factors while obtaining a consistent and reliable system response over time. RPD is conducted under the assumption that the relationship between the system response and controllable and uncontrollable variables does not change over time. Since performance degradation in real-world systems will almost certainly occur; this assumption will inevitably be violated. We propose a methodology to find new levels of controllable factor settings that will be robust to moderate system degradation while remaining robust to noise variables within the system. A gradient-search algorithm is presented for this enhanced RPD analysis utilising quadratic regression.

Keywords: gradient search; quadratic regression; robust design; parameter design; RPD; system degradation; noise variables.

DOI: 10.1504/IJQET.2011.043168

International Journal of Quality Engineering and Technology, 2011 Vol.2 No.4, pp.277 - 290

Published online: 21 Feb 2015 *

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