Direct roll moment control for electric vehicles based on roll angle observer and lateral tire force control

This paper presents roll stability control methodology for future personal electric vehicles with 4 wheel steering system and lateral force sensors. Direct roll moment control is realized by 4 wheel steering control based on lateral tire force control. In this paper, the lateral tire force, obtained from novel lateral force sensors, was utilized to estimate a roll angle and to control the vehicle roll motion. In order to estimate roll angle, a linear observer was proposed and implemented in an experimental electric vehicle. The effectiveness of a proposed roll angle observer was verified through field tests. By using an estimated roll angle, a direct roll moment controller for roll stability was designed based on general two-degree-of-freedom (2-DOF) control methodology. Effectiveness of a proposed roll stability control method was verified through computer simulation using CarSim software.