This paper offers with the theoretical and computational evaluation of optimal & robust control problems, with the goal of providing answers to them with MATLAB simulation. For the robust control, μ-synthesis controller and for the optimal control, LQR controller are designed for a quarter car active suspension system to maximize the ride comfort and road handling criteria’s of the vehicle. The proposed controllers are designed using Matlab script program using time domain analysis for the four road disturbances (bump, random sine pavement and white noise) for the control targets suspension deflection, body acceleration and body travel. Finally the simulation result prove the effectiveness of the active suspension system with μ-synthesis controller.
Table of Contents
I. INTRODUCTION
II. MATHEMATICAL MODEL
A. Quarter Vehicle Active Suspension System Mathematical Model
III. Road Disturbance Input Signals
A. Bump Road Disturbance
B. Random Road Disturbance
C. Sine Pavement Road Disturbance
D. White Noise Road Disturbance
IV. THE PROPOSED µ-SYNTHESIS CONTROL DESIGN
A. µ-Synthesis Controller Design
B. LQR Controller
V. RESULT AND DISCUSSION
A. Comparison of the active suspension system with µ−synthesis and LQR controllers
I. Conclusion
Research Objectives and Themes
This paper aims to evaluate and design optimal and robust control strategies for a quarter-car active suspension system to maximize passenger ride comfort and road handling. Through numerical simulations using MATLAB, the study focuses on minimizing suspension deflection, body acceleration, and body travel under various road disturbance profiles.
- Theoretical and computational evaluation of optimal vs. robust control strategies.
- Application of LQR (Linear Quadratic Regulator) for optimal control.
- Implementation of µ-synthesis controller for robust control.
- Comparative analysis of controller performance under bump, random, sine, and white noise disturbances.
Excerpt from the Book
I. INTRODUCTION
Active suspension system are designed to satisfy specific necessities. In suspension systems, normally two maximum vital capabilities are anticipated to be advanced – disturbance shocking up (i.e. Passenger consolation) and attenuation of the disturbance transfer to the road (i.e. Vehicle dealing with). The first requirement might be supplied as an attenuation of the damped mass acceleration or as a peak minimization of the damped mass vertical displacement. The second one is characterized as an attenuation of the pressure acting on the road or in simple vehicle model as an attenuation of the unsprung mass acceleration. It is apparent that there's a contradiction among those requirements. Effort devoted to passive suspension design is ineffective, due to the fact there is a contradiction among both requirements. The nice end result (in experience of necessities development) can be done by active suspension, this means that that a few additional force can act on system.
The concept of optimal control has been nicely advanced for over forty years. With the advances of computer technique, optimal control is now widely used in multi-disciplinary applications which includes biological structures, conversation networks and socio-monetary systems and so forth. As an end result, increasingly people will benefit greatly via gaining knowledge of to resolve the optimal control problems numerically. Realizing such growing desires, books on optimum control put extra weight on numerical strategies. Necessary situations for diverse systems had been derived and specific solutions were given whilst possible. LQR is a control system that gives the pleasant viable performance with admire to some given degree of performance. The LQR design problem is to design a state feedback controller K such that the objective function J is minimized. In this approach a remarks advantage matrix is designed which minimizes the goal characteristic as a way to obtain some compromise among the use of control effort, the significance, and the speed of reaction so that it will assure a stable system.
Summary of Chapters
I. INTRODUCTION: Introduces the necessity of active suspension systems and discusses the historical evolution and application of optimal control theory in modern engineering.
II. MATHEMATICAL MODEL: Defines the differential motion equations for the quarter-car model and provides the physical parameters used for the simulation.
III. Road Disturbance Input Signals: Describes the four distinct road profiles (bump, random, sine, and white noise) used to test the suspension system's responsiveness.
IV. THE PROPOSED µ-SYNTHESIS CONTROL DESIGN: Details the design process for both the µ-synthesis controller and the LQR controller, including uncertainty modeling and cost function optimization.
V. RESULT AND DISCUSSION: Presents and compares the simulation outcomes for the different controllers across all specified road disturbance conditions.
I. Conclusion: Summarizes the findings, confirming that the µ-synthesis controller provides the best overall performance for the active suspension system.
Keywords
Quarter car active suspension system, optimal control, robust control, linear quadratic regulator, LQR, µ-synthesis controller, MATLAB simulation, road disturbance, suspension deflection, body acceleration, body travel, vehicle dynamics, control systems, state feedback, ride comfort.
Frequently Asked Questions
What is the primary focus of this research?
The paper focuses on the design and evaluation of optimal and robust control systems for a quarter-car active suspension to improve vehicle ride comfort and road handling.
Which control methods are compared in this study?
The study compares the performance of a Linear Quadratic Regulator (LQR) as an optimal controller and a µ-synthesis controller as a robust controller.
What is the main goal of the proposed active suspension system?
The goal is to maximize passenger comfort and vehicle stability by minimizing suspension deflection, body acceleration, and body travel under various road conditions.
Which software is used for the simulation?
The researchers utilized the MATLAB software and script programming to conduct the time-domain analysis.
What types of road disturbances are used to test the system?
The system is tested against four types of disturbances: bump, random, sine pavement, and white noise.
How is the performance of the controllers evaluated?
Performance is evaluated by observing how effectively each controller minimizes target criteria like body acceleration and suspension deflection across the different road profiles.
Why is LQR insufficient as a standalone solution?
The paper suggests that while LQR provides optimal performance, µ-synthesis is investigated to better handle model uncertainties and achieve superior overall performance in varied environments.
What conclusion does the author reach regarding the best controller?
The author concludes that the active suspension system with the µ-synthesis controller provides the best overall performance compared to the LQR-based system.
- Arbeit zitieren
- Mustefa Jibril (Autor:in), 2020, Quarter Car Active Suspension System Design using Optimal and Robust Control Method, München, GRIN Verlag, https://www.hausarbeiten.de/document/542101
