SYSTEM IDENTIFICATION AND CONTROL OF A HYDRAULIC ACTUATOR

Abstract

This paper basically is the modeling and control of an electro-hydraulic actuator which is an important system. It is applied in systems like ships, airplanes, manufacturing systems, process systems, robots, flight and sailing simulators and others. The system was modeled using ARX modeling technique using the system identification toolbox in MATLAB. A fuzzy logic controller was then developed for the electro-hydraulic actuator using Simulink/MATLAB. The Sugeno type fuzzy logic was used and a conventional Proportional Integral Derivative (PID) controller was also developed for comparison. The fuzzy controller outperformed the PID controller, it yields zero steady state error, 2.8% overshoot and settling time of 0.36 seconds. The system response was better with the PID controller which has a 0.0021 or 0.21% steady state error, 4.8% overshoot and settling time of 0.32 seconds. The response parameters of the system without controller are 0.0010 or 0.1% steady state error, an undershoot of 1.4% and 0.54 seconds settling time. Therefore, the controller had improved the system in speed of operation as well as accuracy.