Performance Study of PID Controller and LQR Technique for Inverted Pendulum

Akhil Jose, Clint Augustine, Shinu Mohanan Malola, Keerthi Chacko

Department of Electronics and Instrumentation Engineering, Vimal Jyothi Engineering College, Kannur, India.

DOI: 10.4236/wjet.2015.32008                

Abstract

The inverted pendulum is a classic problem in dynamics and control theory and is widely used as a benchmark for testing control algorithms. It is unstable without control. The process is non linear and unstable with one input signal and several output signals. It is hence obvious that feedback of the state of the pendulum is needed to stabilize the pendulum. The aim of the study is to stabilize the pendulum such that the position of the carriage on the track is controlled quickly and accurately. The problem involves an arm, able to move horizontally in angular motion, and a pendulum, hinged to the arm at the bottom of its length such that the pendulum can move in the same plane as the arm. The conventional PID controller can be used for virtually any process condition. This makes elimination the offset of the proportional mode possible and still provides fast response. In this paper, we have modelled the system and studied conventional controller and LQR controller. It is observed that the LQR method works better compared to conventional controller.

Keywords

Control System, LQR Technique, Conventional Controller, Inverted Pendulum

Conflicts of Interest

The authors declare no conflicts of interest.

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