H-infinity fuzzy adaptive tracking control design for nonlinear systems with output delays Academic Article uri icon

abstract

  • In this study, we develop fuzzy adaptive tracking control via two-layer fuzzy observers, variable structure systems (VSS), and H control algorithm for nonlinear systems with plant uncertainties, output delays, and external disturbances. The Takagi-Sugeno fuzzy dynamic model with adaptation capability is used to approximate the nonlinear system. When the system states are not available, the states estimated from two-layer fuzzy observers combined with VSS are used to develop the fuzzy adaptive controller. In the first layer, the output delays are partitioned into m+1 equal time intervals to construct the same number of fuzzy observers. The output delayed states in each time interval are used as the premise variables in the IF-THEN rules. The second layer of the fuzzy observers uses output delayed error states as its linguistic variables and it is defuzzified from the first layer. Next, we develop a fuzzy adaptive controller to overcome the nonlinearities, output delayed states, and external disturbances such that H tracking performance is achieved. The Lyapunov criterion and linear matrix inequalities are used to derive the controller. In the present study, our previous method is extended to handle a class of uncertain nonlinear systems with output delays and external disturbances, which is achieved using robust VSS and H control techniques. A magnetic levitation system and inverted pendulum system are used as simulation examples to illustrate the validity and confirm the performance of our proposed scheme. 2014 Elsevier B.V.

published proceedings

  • FUZZY SETS AND SYSTEMS

author list (cited authors)

  • Wu, T., & Karkoub, M.

citation count

  • 17

complete list of authors

  • Wu, Tzu-Sung||Karkoub, Mansour

publication date

  • November 2014