Modeling and Control of Nonlinear Systems

Abstract

Known the suspension types Three categories passive suspension, and classified of a semi-active suspension, and active suspension are used to categorize suspension systems. In the first decades of the 20th century, the phrase "quarter car model" first appeared. It is regarded as the most effective method for examining the efficiency of vehicle stability. The mathematical model represents a spring mass (Quarter of the chassis) and an unsprung mass (the wheel), with two degrees of freedom (2-DOF) system characterized by a pair of differential equations. This dissertation discusses the modeling and control of a nonlinear active suspension system for a quarter car. Finding a control method that will give superior performance in terms of sprung displacement, sprung mass velocity, suspension deflection, peak overshoot, and setting time is the goal of this effort because the conventional PID and FOPID did not produce satisfactory results, the active control of the suspension system is accomplished using PID and Fractional-Order PID (FOPID) modified using Particle Swarm Optimization algorithms (PSO algorithms) and Genetic Algorithms (GA). On the other hand, we manage the system using the Linear Quadratic Regulator (LQR) or other words optimal control. MATLAB/Simulink is used to design and simulate the results. In comparison to Passive suspension, intelligent PID, and intelligent FOPID controller, with LQR control. It has been found that the LQR controller provides greater ride comfort by lowering the RMS error and vibration of various types of road conditions.