Adjustable Valve Semi-Active Suspension System for Passenger Car

Abstract

The suspension of the car plays a very important role in the safety and the comfort of the vehicle and for absorbing the shock waves and give comfort for the driver and passenger. This paper improves the performance of an automobile suspension system by developing electronically adjustable semi-active shock absorber. This achieved by attaching stepper motor for each shock absorber which helps in adjusting the bleed orifice to a certain position that alternates the hydraulic oil flow in the shock absorber between piston’s chamber during the process of compression and rebound. To evaluate the effect of developed semi-active shock absorber on the dynamic behaviour of the vehicle, several tests were carried out on different types of road condition (bumpy, straight-line and roundabout). These tests were used to evaluate the acceleration and ride quality. There is a great range in response when the bleed orifice is opened reached up to 35% between the stiff and soft setting. The value of root means square acceleration (RMS) was calculated and compared with the standard of human exposure to whole-body vibration, which shows an error of 6% slightly. The result shows the effect of electronically controllable shock absorber on a vehicle’s dynamic behaviour — the advantage of electronics to improve the performance of ride comfort and reduced the harms due to undesired vibration.