Design of Fuzzy logic controller to series active variable geometry suspension system of automobile vehicle using full car model (With preview road profile information)

Abstract

Recent advancements in electro-mechanical active suspensions are presenting new opportunities, showcasing numerous benefits over traditional passive and semi-active systems, while also overcoming the significant drawbacks of other active solutions. This thesis introduces fuzzy logic controller with perfect preview information to improve the performance of Series Active Variable Geometry Suspension (SAVGS), which enhances conventional independent passive or semi-active suspensions by actively regulating the suspension geometry through an electromechanical actuator. The research work explores the benefits of this suspension type and provides an in-depth analysis of its simplest form. Additionally, it offers insights into the design process, including liberalized full-car modeling and selection. A control system designed to manage pitch and roll attitude of the chassis is also discussed. Simulation results demonstrate the viability of the proposed system as the fuzzy logic controller (FLC) is developed using MATLAB-Simulink for the SAVGS improves the suspension system, with various performance metrics (Passenger Ride Comfort, Suspension Safety, and Road Handling) evaluated at different speed for Road disturbance. The performance response at 20 kilometer per hour shows improvement in all the performance metrics, like in Passenger ride comfort is reduced in Vertical acceleration by 41.67% with reduced pitch and roll acceleration, Suspension safety is reduced in suspension deflection by 49.1% in front and 43.1% in rear sides with reduced velocity, and in road handling the tire deflection reduces by 46.3% at front and 36.9% at the rear sides of the car