GT Car's CG height control on a rough road by using series active variable geometry suspension

Document Type : Invited by Davoud Younesian


School of Automotive Engineering, Iran University of Science and Technology, Tehran, Iran



This paper addresses the vehicle's CG (center of gravity) height control enhancement for the new road vehicle Series Active Variable Geometry Suspension (SAVGS) concept using the PID control technique. Thus, the study utilizes a nonlinear full-car model that accurately represents the dynamics and geometry of a high-performance car with the new double-wishbone active suspension concept. The proposed controller is installed on the nonlinear full-car model, and its performance is examined by the parameters CG Height and Pitch. In this study, PID is tuned by a Genetic Algorithm, and thus, a robust control system is designed. Finally, the system's robustness is examined through four different simulation configurations, such as different speeds and different road conditions. The vehicle is supposed to be moving to 20 km/h and 100 km/h horizontal speed, and also it is going through Road Classes types C and D. Figures show that this suspension system successfully controls vehicle CG height around a desirable height (0.5m) and does not make harmful impacts on vehicle pitch angle.


  • The use of a simple optimized PID controller on a vehicle with SAVGS is proposed.
  • Studying SAVGS on rough surfaces is the second contribution of this paper.
  • Using GA for PID tuning is found having good performance for controller optimization.
  • Having vehicle’s Height Control as the main objective of the SAVGS tuning is proposed.


Main Subjects

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