Multirate output feedback based controllers for non-linear inverted pendulum system

Abstract

Multirate output feedback (MROF) techniques have attracted the interest of many researchers for the design of controller, as these methods are based on output feedback and are at the same time capable of assigning arbitrary dynamical characteristics to the closed loop system. Fast output sampling (FOS) is a kind of MROF, in which the states of the system can be computed from the output of the system. In this paper, different techniques of FOS based controllers are investigated for non-linear system of inverted pendulum (IP). Control laws are designed using linear model of IP system. The first control law is constructed based on past output observations. In second control law, past output observations alongwith past input is used for design purpose. However, in third case, discrete-time sliding mode control (DSMC) in combination with FOS feedback, presented in second control law, is formulated. Simulations have been carried out using non-linear model of IP system developed in MatLab/Simulink environment. From simulations it is observed that, the performance of FOS feedback based DSMC is comparatively better than other control techniques.