Toward systematic approaches to design and implement vehicles semi-active control systems

Abstract

In this paper a systematic while practical methodology has been presented for design of vehicle's semiactive suspension systems. The semi-active control strategies developed to improve vehicle ride comfort and stability generally have a switching nature. This makes the design of the controlled suspension systems difficult and highly dependent on an extensive trial and error process. The proposed methodology maps the discontinuous control system model to a continuous linear region where all the time/frequency design techniques established in the conventional control system theory can be applied. If the semiactive control system is designed to satisfy some ride/stability requirements, an inverse mapping offers control law. The effectiveness of the proposed design methodology in dealing with real industrial problems is demonstrated with experimental results.

Fuzzy Control of Vehicle Suspension System

“…Suspension of a vehicle has to maintain the contact between the tire and the road surface to ensure the stability of the vehicle while, on the other hand, the suspension system should isolate the vehicle frame from road induced vibrations. The main concern in suspension design and control is achieving improvements in these conflicting tasks and computer-controlled suspensions try to reach, at a small cost penalty, a tradeoff between riding comfort and vehicle handling, superior to that achievable by conventional passive suspensions [1][2][3]. Inherently, passive suspensions can only perform well in a limited range of operating conditions and therefore the primary purpose of adopting an active/semi-active suspension system is to broaden this optimal range as much as possible.…”