Iterated non-linear model predictive control based on tubes and contractive constraints. (May 2016)

• Record Type: Journal Article
• Authors: Murillo, M.; Sánchez, G.; Giovanini, L.
• Is Part Of: ISA transactions. Volume 62(2016:May)
• Page Start: 120
• Page End: 128
• Publication Date: 2016-05
• Subjects: Contractive constraint -- Iterative process -- Non-linear model predictive control -- Robust model predictive control; Engineering instruments -- Periodicals; Engineering instruments; Periodicals; Electronic journals; 629.805
• DOI: 10.1016/j.isatra.2016.01.008
• Languages: English
• ISSNs: 0019-0578

Abstract

Abstract: This paper presents a predictive control algorithm for non-linear systems based on successive linearizations of the non-linear dynamic around a given trajectory. A linear time varying model is obtained and the non-convex constrained optimization problem is transformed into a sequence of locally convex ones. The robustness of the proposed algorithm is addressed adding a convex contractive constraint. To account for linearization errors and to obtain more accurate results an inner iteration loop is added to the algorithm. A simple methodology to obtain an outer bounding-tube for state trajectories is also presented. The convergence of the iterative process and the stability of the closed-loop system are analyzed. The simulation results show the effectiveness of the proposed algorithm in controlling a quadcopter type unmanned aerial vehicle. Abstract : Highlights: Predictive control algorithm for non-linear systems. Addition of contractive constraints to the optimization problem to guarantee the stability issues. Proposal of a simple methodology to achieve outer bounding-tubes for state trajectories. Simulation results for short and long prediction horizons are shown.