Performance of PID controller both in hard and soft RTOS

Abstract

This paper presents the performance improvement of hard real-time PID (proportional + integral + derivative) controller over the soft real-time one. PID controller is a generic control loop feedback mechanism widely used in industrial control system. For hard real-time PID implementation, we have considered PID controller algorithm in RT-Linux operating system. To achieve an efficient result a sampling rate of 10 msec is considered. The system performance has been analyzed (for both hard real-time and soft real-time) in time domain. In this regard, we performed a laboratory test on servo system for both soft real-time (windows based) and hard real-time (RT-Linux based) PID controller. The test results of our laboratory experiments clearly illustrates that the hard real-time PID controller perform better than soft real-time PID controller.