INFLUENCE OF ACTIVE CHASSIS SYSTEMS ON VEHICLE PROPENSITY TO MANEUVER-INDUCED ROLLOVERS. IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS

Abstract

With the growing popularity of vehicles with high centers of gravity, the evaluation of rollover propensity of these vehicles becomes an issue of increasing importance. This chapter on the influence of active chassis systems on vehicle propensity to maneuver-induced rollovers is from a comprehensive textbook on occupant and vehicle responses in rollovers. The author considers the influence of three presently-available controlled chassis systems on vehicle rollover resistance. The systems are the active rear steer (ARS), the brake based vehicle stability enhancement system (VSE), and the active roll bar, referred to as dynamic body control (DBC) system. A 16 degree-of-freedom computer model of a full vehicle is used for the study. The maneuvers used in the simulation are the double lane change and the fishhook maneuvers, with increasing steering amplitudes. The results show that the uncontrolled vehicle rolls over in both maneuvers when the steering angle is sufficiently large. The author concluded that all three systems improved vehicle resistance to rollovers, but DBC system was the least effective (primarily due to insufficient speed of response, limited by the power of the hydraulic pump). The VSE system improved vehicle stability more than the ARS system did, and the vehicle with both of these control systems was the most stable of all.