Document Type : Research Paper


1 Mechanical Eng. Dept. University of Technology - Iraq

2 Mechanical Eng. Dept., University of Technology - Iraq


Passive hydraulic dampers are commonly used in the automotive suspension system. Nevertheless, they are suffering from a significant drawback owing to the changing of its characteristics at high-frequency; as a result, decreasing the ride quality due to the increase of the transmitted force, especially at high frequency excitations. The present work developed a semi-active suspension system to solve this problem with its effect. A Sky-hook control strategy is used to suppress the positional oscillation of the sprung mass in the presence of road irregularities via the use of the electrohydraulic (EH) damper, as an objective. In order to apply the control strategy used herein, a full-scale quarter-car test platform has been designed and constructed to offer increased testing flexibility at a reasonable cost not found commercially. MATLAB Simulink is applied for modeling the semi-active suspension system. The control strategy using a Sky-hook control was used to enhance the comfort due to the simplicity of this method that can easily be implemented in a real-time embedded application. The control strategy is evaluated for its performance under the road bump excitation. The experimental results were compared with the simulated ones for both passive and semi-active suspension systems, the comparison includes time response analysis of body vertical displacement, and vertical displacement of quarter car structure.


Main Subjects

[1] S. Kashem “Vehicle Suspension Systems and
Electromagnetic Dampers,” Springer Singapore, 2018.
[2] S. Sulaiman, P.M. Samin, H. Jamaluddin, R.A.
Rahman, and S. A. Abu Bakar, “Tire Force Control
Strategy for Semi Active Magnetorheological Damper
Suspension System using Quarter Heavy Vehicle Model,”
Applied Mechanics and Materials, pp. 789-790, 2015.
[3] D. Huang, J.Q. Zhang, and Y.L. Liu, “The PID SemiActive Vibration Control on Nonlinear Suspension System
with Time Delay,” International Journal of Intelligent
Transportation Systems Research, Volume 16, Issue 2, pp
125–137, 2018.
[4] X. Tang, H. Du, S. Sun, D. Ning, Z. Xing, and W. Li
“Takagi-Sugeno fuzzy control for semi-active vehicle
suspension with an magneto-rheological damper and
experimental validation,” IEEE/ASME Transactions on
Mechatronics, Vol. 22, Issue: 1, 2017.
[5] H. Elahi, A. Israr, M.Z. Khan, and S. Ahmad, “Robust
Vehicle Suspension System by Converting Active &
Passive Control of a Vehicle to Semi-Active Control
System Analytically,” Journal of Automation and Control
Engineering, Vol. 4, No. 4, 2016.
[6] G. Ślaski, “Damping Parameters of Suspension of
Passenger Vehicle Equipped With Semi-Active Dampers
with By-Pass Valve,” Transport Problems, Vol. 6, Issue 2,
[7] A. Malekshahi, and M. Mirzaei, “Designing A NonLinear Tracking Controller For Vehicle Active Suspension
Systems Using An Optimization Process,” International
Journal of Automotive Technology, Vol. 13, No. 2, pp.
263−27, 2012.
[8] F. Yakub, P. Muhammad, Z.H.C. Daud, A. Abd
Fatah, Y. Mori “Ride Comfort Quality Improvement for a
Quarter Car Semi-Active Suspension System via StateFeedback Controller,” Asian Control Conference (ASCC)
IEEE, 2017.
[9] A. Mulla, S. Jalwadi, and D. Unaune, “Performance
Analysis of Skyhook, Groundhook and Hybrid Control
Strategies on Semiactive Suspension System,”
International Journal of Current Engineering and
Technology, Special Issue-3, 2014.
[10] Y. Chen, Z.L. Wang, J. Qiu, and H.Z. Huang “Hybrid
Fuzzy Skyhook Surface Control Using Multi-Objective
Microgenetic Algorithm for Semi-Active Vehicle
Suspension System Ride Comfort Stability Analysis,”
Journal of Dynamic Systems, Measurement, and Control,
Vol. 134, pp 2012.
[11] X. Song, “Cost-Effective Skyhook Control for
Semiactive Vehicle Suspension Applications,” The Open
Mechanical Engineering Journal, 3, 17-25, 2009.
[12] E. Guglielmino, T. Sireteanu, C.W. Stammers, G.
Ghita, and M. Giuclea, “Semi-active Suspension Control:
Improved Vehicle Ride and Road Friendliness,” Springer,
[13] T. Lingfeng, and L. Shengwen, “PID-Fuzzy control
research on hydraulic semi-active suspension system of
car,” International Conference on Educational and
Network Technology (ICENT 2010).
[14] A. Raj, S. Shrivastava, and M.W. Trikande,
“Modelling and Analysis of Skyhook and Fuzzy Logic
Controls in Semi-Active Suspension System,”
International Conference on Industrial Instrumentation and
Control (IClC), 2015 IEEE.