Simulation and Experimental Research on Active Suspension System With Time-Delay Feedback Control.

A 2-DOF vehicle active suspension system model with time-delay feedback control is established. The stability region of the time-delay active suspension system is obtained by using the Routh-Hurwitz stability criterion and polynomial discriminant theory. The multi-objective optimization function is established taking into account vehicle ride comfort, driving safety, and handling stability, and the optimal feedback parameters are obtained by the particle swarm optimization(PSO) algorithm. The vibration characteristics of active suspension systems with time-delay under different road excitations are studied through experiments and simulations and then compared with passive uncontrolled suspension and active suspension based on LQR. The experimental results show that the sprung mass acceleration(SMA) of the active suspension system with optimal time-delay feedback control under harmonic excitation is reduced by 58.02% and 39.18% compared to the passive suspension system and the LQR active suspension system, respectively. Meanwhile, the sprung mass acceleration of the active suspension system with optimal time-delay feedback control under random excitation has a 69.56% and 35.50% reduction compared to the passive suspension system and the LQR active suspension system, respectively. The performance of active suspension controlled by time-delay feedback is better than that of passive suspension and LQR active suspension in numerical study and experiment. Moreover, the experimental and simulation results show good consistency, which proves the reliability of the experimental results.