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Malar Mohan K

Abstract

The increased concern on ride comfort and handling characteristics of an automobile have led to extensive research on automobile suspension systems. The authors of this article propose an adaptive air suspension system with LQR control strategy. The LQR controller is tuned by a combination of PSO and manual tuning. A dynamic model of the air suspension system used in passenger vehicles is designed and simulated for both passive and adaptive systems using MATLAB/Simulink. Air suspension is a non-linear system and thus the authors have derived a stiffness equation for the same with minimal assumptions. A comparative analysis is performed with the widely used PID controller to compare the efficiency of the proposed controller. The results are obtained for bumps, pot holes and ISO standard random road conditions. The settling time, peak displacement and tuning strategies are compared and analyzed. The results show that the adaptive system can achieve better vibration isolation compared to passive system. On comparing the analysis parameters, it is seen that the LQR controller has better potential to improve ride comfort by reducing the maximum displacement amplitude of the vehicle by 89.88% and provide better handling characteristics by reducing the settling time of the system by 85%.

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References

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