Extended Stability Envelopes and Effectiveness Quantification for Integrated Chassis Control With Multiple Actuator Configurations in the Energy Phase Plane

Abstract

The emerged integrated chassis is playing an increasingly pivotal role in enhancing vehicle stability, which typically needs estimation of the stability envelope and proper coordination strategy for chassis controller design. The conventional stability envelope determined in phase plane ensure vehicle self-stability, while it neglects the influence of chassis actuators. To play out full performance of integrated chassis, this study proposes a novel extended stability envelope analysis method to quantify the effect of different chassis actuator combinations on vehicle lateral dynamic. In energy phase plane, the state change direction with influence of control inputs are employed to judge whether a given state will go beyond the tire’s grip limit. Accordingly extended stability envelopes of some typical actuator combinations, i.e., active front steering (AFS) and active rear steering (ARS), AFS and torque vectoring control (TVC), ARS and TVC, are determined. Meanwhile, principle to quantify the overlapping effectiveness range and unique effectiveness range between ARS and TVC is introduced, accordingly effectiveness factors used for coordination control are discussed. In summary, the proposed method in this article has considerable potential for coordination control of integrated chassis, by providing comprehensive analysis method to estimate the extended stability boundary and quantify the effectiveness range with influence of actuators taken into account.