In this paper the importance of self tuning adaptive PID control scheme for automotive suspension system is explained. The objective of this study is to obtain a mathematical model for the passive and semi-active suspension system for quarter car model. Current automobile suspension system employs springs and damper with fixed coefficient. Vehicle suspension systems are typically rated by their...

In this work we obtain a new description of the vertical motion of the car including the active suspension. It consists of 4 completely decoupled subsystems. The first 3 ones are of order 4 each and they are analogous to standard quarter car suspension models. The 4th subsystem is of order 2 and it introduces a new abstract variable denoted by γ. One of the novelties of this modeling result is ...

This paper studies order reduction issues for a vehicle active suspension system throughout its modelling, H-infinity controller design and controller refinement. Computer simulations demonstrate that an H-infinity controller for a full active suspension can be significantly reduced to nearly one third of its full order, while the active suspension performance is only slightly degraded. As a by...

The use of fractional differentiation in vehicle suspension design has many interests. This paper presents a hydropneumatic suspensions design method based on fractional differentiation. Once an hydraulic structure has been chosen for the suspension, it is possible to calculate the values of all technological parameters, so that the suspension force deflection transfer function is a band-limite...

A nonlinear model consisting “yaw, roll, longitudinal, lateral and pitch” has been developed in which, tire and suspension characteristics have been considered. Tire model is based on the elliptic concept and tire Calspan data. According to this tire model, cornering force and aligning moment are computed as a function of slip and camber (inclination) angles, normal load, tire adhesion characte...

In this paper an H∞ controller is designed for a hydraulically actuated active suspension system of a half-modeled vehicle in a cascade feedback structure. Using the proposed structure the nonlinear behavior of actuator is reduced significantly. In the controller synthesis, a proportional controller is used in the inner loop, and a robust H∞ controller forms the outer loop. Two H∞ controllers a...

In this work, using a quarter-car model was adopted, the equations of motion were derived for passive and then sky-hook semi-active suspension systems. The differential equations, solved Dormand-Prince pair numerical formula, used to simulate values displacements as affected by damping coefficients constant. simulated results showed that maximum amplitude sprung mass, which is linked ride disco...