Modeling of full vehicle dynamics for enhanced stability control

Abstract

Dynamic models utilized for assessing vehicle stability typically possess a limited number of degrees of freedom, commonly known as a planar model. Simultaneous examination of vibration and stability is unfeasible within these models. Additionally, such models pose several challenges in terms of adaptation to emerging vehicle technologies, rendering them unsuitable for real-time control. Furthermore, the dependability of outcomes derived from dynamic systems with limited degrees of freedom remains uncertain. This article presents a theoretical and experimental comparison analysis of a dynamic model designed to assess the vibration and motion stability of a vehicle with twelve degrees of freedom. The empirical investigations were conducted under actual road conditions, employing a four-step approach: horizontal vehicle model, vertical vehicle model, liner tyre model, and driver model. The experiment shows that a error was close to 15% when the speed of movement increased from 75-80 km/h in the 12DOF model, likely due to the linearity of the tire model. This is due to the non-linear elastics of the steering and suspension, as well as the kinematic introduction during the turn of the car. Based on the conducted research, it is recommended to use non-linear models of tires and suspensions in further studies.