VEHICLE CORNERING CHARACTERISTICS IN ACCELERATION AND BRAKING THROUGHATTITUDE-CONTROL OF FRONT AND REAR TIRES

A new active control method for the attitude angles of wheels is propo sed to improve the the maneuverability and stability of automobiles. F rom theoretical analysis and computer simulation, it is clarified that this control yields satisfactory vehicle cornering performances durin g steering, acceleration and braking. The dynamics of lateral movement and yawing of the vehicle as a result of tire attitude control are in vestigated using a quasi-steady-state analysis model for the case of t ractive or braking force. An extended stability factor related to the characteristics of toe and camber angles of wheels is defined, which i s applicable to circular turnings with lateral and longitudinal accele rations. Effects of control are analyzed using this factor, Furthermor e, a modified control method is proposed, which makes it possible not only to improve vehicle dynamics but also to decrease actuating values of attitude angles in actual driving.