LQ digital control of ball & plate system

Abstract

This paper proposes the design of linear quadratic (LQ) digital controller for Ball & Plate model and 2DOF structure of the controller. Unknown parameters of the controller are determined with the help of polynomial approach to controller design. Semi-optimal solution is obtained using minimization of linear quadratic criterion. Spectral factorization with the aid of the Polynomial Toolbox for MATLAB was used for minimization of this LQ criterion. Additional poles of characteristic polynomial are placed so that the process is subtle and without sudden changes in controller output. Results have shown that the controller is able to stabilize the ball in desired position on the plate, reject external disturbances and follow reference path without much effort. Controller was designed for step changing and harmonic reference signal to further examine its capabilities. © ECMS Zita Zoltay Paprika, Péter Horák, Kata Váradi,Péter Tamás Zwierczyk, Ágnes Vidovics-Dancs, János Péter Rádics (Editors).