ABSTRACT
ABSTRACT: A phase-plane based joint criterion combing the sideslip angle method and the yaw rate method is proposed, which can coordinate the control of both vehicle sideslip angle and yaw rate. The data base of the stable region thresholds are obtained by means of the phase-plane method. And look-up tables of the thresholds are established for real-time control. A vehicle stability control strategy utilizing direct yaw moment control with a hierarchical structure is designed to keep vehicle states within the stable region defined by the proposed joint vehicle stability criterion. Considering tires nonlinear characteristics under critical conditions, a self-tuning LQR based on tire cornering stiffness estimation is designed for motion tracking. A torque allocation algorithm distributes the generalized force to four independent in-wheel motors. Experiments are carried out to verify effects of the control strategy.
