Recently, active suspension system has been researched and adopted widely in order to compromise the conflicting requirements of ride comfort and vehicle handling. Not only passenger car but also commercial vehicles like trucks or buses require the active suspension system to reduce road damage, to protect cargos from external impacts, to improve the ride comfort of driver, and to maintain the vehicle stability.
In this paper, in order to improve vehicle's rollover stability during hard cornering, a roll control algorithm for slow-active suspension is developed based on a 4-DOF linear roll model which considers Body Torsional Stiffness for long wheel-base vehicles. MIMO generalized predictive control method is used to construct the controller, and resulting roll control performance and feasibility are checked by computer simulation using the nonlinear simulation model including body torsional mode. Improvement of rollover threshold in frequency domain is also noted.
