Investigation of Lateral and Vertical Direction Dynamic Responses of a Full Car Model Exposed to Sine Road Input

Abstract

In this study, the full car model, which is exposed to a sinusoidal road input, has been examined to ensure the driving safety of the vehicles and the comfort of the passengers. In this context, the full car, including lateral and vertical movements, is modeled with fourteen degrees of freedom. The second-order equations of motion of the modeled vehicle were obtained using the Lagrangian method and reduced to first-order equations of motion using the state-space form. Then, these equations of motion were solved precisely in the time domain using the Euler method in the Matlab environment. To examine the lateral movements and the rotations of the vehicle in the pitch and roll axis, a sine wave with a wavelength of 5 m and an amplitude of 0.1 m was applied to the wheels of the vehicle. In the analysis, the right front wheel is exposed to a sinusoidal road input at t=0 s, while the left front wheel is exposed to a sinusoidal road input after the vehicle moves 2.5 m. Thus, both the pitch and roll motion of the vehicle will be examined in detail. In the study, four different vehicle masses 500 kg, 1000 kg, 2000 kg, and 3000 kg were taken into consideration and the effect of different vehicle masses on passenger and vehicle dynamic behaviors was investigated. In addition, the situation of passing vehicles at variable speeds from the given disruptive road input has also been examined. The maximum dynamic responses of the passenger and the vehicle were examined when the vehicle speed changed from 3 m/s to 50 m/s by 0.1 m/s. In the study, it has been observed that the vehicle mass and certain vehicle speed have effects on the vertical and lateral displacements and accelerations of the passenger and the vehicle