Global Journal of Researches in Engineering, A: Mechanical & Mechanics, Volume 22 Issue 1

Global Journal of Researches in Engineering (A ) Volume XxXII Issue I Version I 55 Year 2022 © 2022 Global Journals Vibrational Behaviour of a Quarter Car Travelling over Road Humps with Different Suspension Systems suspension system is used while, this value is reduced to about 7 m/s 2 as active suspension system is applied. In the same context, the suspension working space is considerably reduced as the semi-active suspension system is applied in comparison with passive suspension system. Moreover, dynamic tire load reduced as the semi-active suspension system is applied in comparison with passive suspension system. Looking at the body displacement of the vehicle, there is a slight improvement when using active suspension system compared with passive suspension system. Figure 9: Vibrational behaviour of vehicle over circular hump at 50 km/h Fig. (9) illustrates the dynamic vibrational behaviour of a quarter car that is travelling over a circular hump at 50 km/h with the passive, the semi- active and the active suspension systems. The body vertical acceleration is severely increased because of the vehicle speed is higher and hence the vehicle ride comfort is important element. The using of the semi- active suspension resulted in a slight improvement in the beginning of the hump crossing and this improvement increased at the end of the hump as a result of the controller response. By using of the active suspension resulted in a significant improvement in ride comfort compared to other suspension systems. However, the maximum value of the body vertical acceleration is about 13 m/s 2 as a passive suspension system is used while, this value is reduced to about 10 m/s 2 as active suspension system is applied. The suspension working space is considerably reduced for both suspension systems. As the semi-active suspension system is applied, a considerable reduction in suspension working space is achieved in comparison with passive suspension system. The body displacement of the vehicle, there is a slight improvement when the semi-active suspension system is used referred to the passive suspension system. Figure 10: Vibrational behaviour of vehicle over trapezoidal hump at 30 km/h