Automotive Science and Engineering

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Non-linear characteristic of tire forces is the main cause of vehicle lateral dynamics instability, while direct yaw moment control is an effective method to recover the vehicle stability. In this paper, an optimal linear quadratic regulator (LQR) controller for roll-yaw dynamics to articulated heavy vehicles is developed. For this purpose, the equations of motion obtained by the MATLAB software are coded and then a control law is introduced by minimizing the local differences between the predicted and the desired responses. The influence of some parameters such as the anti roll bar, change the parameters of the suspension system and track wide in articulated heavy vehicles stability has been studied. The simulation results show that the vehicle stability can be remarkably improved when the optimal linear controller is applied

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This paper presents a reduce roll vibration of the full vehicle model with passive suspension systems using vibration absorber to change the dynamic system matrix stat’s eigenvalue. Since using the controller system has been splurged and required to energy consuming, in this research the vehicle body roll vibration has been reduced and supplied vehicle stability using a vibration absorber for the passive suspension system. In this paper a new manner is introduced to reduce body roll angle and body's roll acceleration. The transverse instability in the independent suspension is a main problem, roll angle decreased transverse stability, that it has been reduced using vibration absorber. The optimal value of vibration absorber’s mass, spring and damping coefficient has been determined by using genetic algorithms (GA) to achieve developed roll angle behavior. The main purpose of this article is to reduce vehicle body roll angle that has been acquired using vibration absorber, this manner is better than other ways for roll reduction of vehicle body because it has done without any energy consuming.