Robust vehicle suspension system by converting active and passive control of a vehicle to semi-active control ystem analytically

This research article deals with a simplified translational model of an automotive suspension system which is constructed by considering the translation motion of one wheel of a car. Passive Vehicle Suspension System is converted into Semi Active Vehicle System. Major advantage achieved by this system is that it adjusts the damping of the suspension system without the application of any actuator by using MATLAB® simulations. The semi-active control is found to control the vibration of suspension system very well

State of the art of control schemes for smart systems featuring magneto-rheological materials

This review presents various control strategies for application systems utilizing smart magneto-rheological fluid (MRF) and magneto-rheological elastomers (MRE). It is well known that both MRF and MRE are actively studied and applied to many practical systems such as vehicle dampers. The mandatory requirements for successful applications of MRF and MRE include several factors: advanced material properties, optimal mechanisms, suitable modeling, and appropriate control schemes. Among these requirements, the use of an appropriate control scheme is a crucial factor since it is the final action stage of the application systems to achieve the desired output responses. There are numerous different control strategies which have been applied to many different application systems of MRF and MRE, summarized in this review. In the literature review, advantages and disadvantages of each control scheme are discussed so that potential researchers can develop more effective strategies to achieve higher control performance of many application systems utilizing magneto-rheological materials

Prototyping a new car semi-active suspension by variational feedback controller

New suspension systems electronically controlled are presented and mounted on board of a real car. The system consists of variable semi-active magneto-rheological dampers that are controlled through an electronic unit that is designed on the basis of a new optimal theoretical control, named VFC-Variational Feedback Controller. The system has been mounted on board of a BMW Series 1 car, and a set of experimental tests have been conducted in real driving conditions. The VFC reveals, because of its design strategy, to be able to enhance simultaneously both the comfort performance as well as the handling capability of the car. Preliminary comparisons with several industrially control methods adopted in the automotive field, among them skyhook and groundhook, show excellent results

Multiphysics Analysis of a Magnetorheological Damper

     A Magnetorheological damping has evolved as a potential tool in vibration control. The design of magnetorheological damping involves analysis of fluid flow principles and electromagnetic flux analysis. This research paper involves design and analysis of a magnetorheological damper employed for vibration control. The analysis is carried over by considering the domain as an axisymmetric model. The damping force of the damper depends upon the shear stress due to fluid viscosity and yield stress induced due to magnetic flux applied. The damping force generated by the damper is calculated

Modeling, Analysis and Testing of a Semi-Active Control System for Landing Gear Applications

There have been several recent studies on the potential benefits of controllable dampers. Controllable dampers can use a fluid with controllable properties, such as Magneto - Rheological fluid (MR fluid), or control the damping force by changing orifice size. For this project, controllable dampers were created using MR fluid. When exposed to a magnetic fluid, the viscosity of MR fluid can change significantly. By replacing the standard damper oil in an aircraft landing gear and exposing the system to an appropriate magnetic field, the damping coefficients of the system can be changed almost instantaneously to accommodate nearly any situation. This trait allows a real time controller to monitor the system and adjust damping characteristics to match current conditions. Using the \u27no-jerk\u27 Skyhook control strategy, the control system attempts to minimize the acceleration, force and displacement transmitted to the fuselage from the ground. This reduction in applied load can translate into reduced aircraft weight, and longer fatigue life for some components. Unlike previous studies, the controllable damper configuration for this project used an externally mounted electromagnet located between the damper and remote reservoir, as opposed to an electromagnet located internal to the damper body. This design allows landing gear to use semi-active MR dampers with few modifications to existing designs. A set of dampers were tested in the standard and controllable configurations on a shock dynamometer. A SimMechanics model, which was calibrated using the dynamometer data and from limited 2-DOF experimental test data, was used to predict the improvement in transmissibility resulting from these modifications. The results indicate that controllable dampers using a ‘no jerk\u27 skyhook control policy can reduce transmissibility of ground input to the fuselage

A Semiactive Vibration Control Design for Suspension Systems with Mr Dampers

Published version of a chapter published in the book: Vibration Analysis and Control - New Trends and Developments. Also available from the publisher at: http://www.intechopen.com/source/pdfs/17688/InTech-A_semiactive_vibration_control_design_for_suspension_systems_with_mr_dampers.pdf. O

Neutral network-PID control algorithm for semi-active suspensions with magneto-rheological damper

In this paper, a semi-active suspension control system based on Magneto-Rheological (MR) damper is designed for a commercial vehicle to improve the ride comfort and driving stability. A mathematical model of MR damper based on the Bouc-Wen hysteresis model is built. The mathematical model could precisely describe the characteristics of MR damper compared with the bench test results. The neural network-PID controller is designed for the semi-active suspension systems. According to the numerical results, the proposed controller can constrain vehicle vibrations and roll angle significantly. A detailed multi-body dynamic model of the light vehicle with four semi-active suspensions are established, and an actual vehicle handling and stability tests are carried out to verify the control performances of the proposed controller. It can be concluded that MR semi-active suspension systems can play a key role in coordination between the ride comfort and handling stability for the commercial vehicle

Linear quadratic regulator applied to a magnetorheological damper aiming attenuate vibration in an automotive suspension

Automotive suspension is a mechanical device used in automobiles to attenuate vibrations, which are caused by the undulation of the floor. This device can be modeled by a mass-spring-damper system, and the damper used in most real situations is a viscous medium damper, which dissipates energy passively. In this work, a 1/4 model of automotive suspension was analyzed when the passive shock absorber is exchanged for a magnetorheological shock absorber, whose control current is determined by a law of Optimal Linear Control. Based on the analyzes made in terms of displacement and acceleration, more satisfactory results were obtained in the system containing the AMR, in contrast to the results obtained with the presence of the passive damper