Abstract:

new type of nonlinear active anti-roll bar with variable torsional stiffness was designed to improve the anti-rollover ability in emergency obstacle avoidance and uneven pavement of heavy commercial vehicle. A vehicle dynamics model with active anti-roll bar of eight degrees of freedom was proposed. Using the genetic
algorithm and linear quadratic regulator optimal control theory, the vehicle active anti-roll control simulation was analyzed with the vehicle of new anti-roll bar system. The results show that the anti-roll bar’s torsion stiffness changes with the pavement impact or the centrifugal force during turning by changing the distance between the anti-roll bar automatically. Comparison with the passive anti-roll bar, in high speed turning, the vehicle’s average roll angle with active anti-roll bar reduces by 30%, the anti-roll torque increases by about 13%, and the lateral load transfer rate reduces by about 20%; in small lateral acceleration, the anti-roll torque increases by about 44%, the lateral transfer rate reduces by about 23%, which proves that the active anti-roll bar and its control strategy can effectively improve vehicle ride comfort and anti-roll capability.

Key words: automotive engineering, variable torsional stiffness, active anti-roll bar, linear quadratic regulator (LQR) control, active anti-roll control