Interval Uncertain Optimization of Vehicle Suspension forRide Comfort

Based on the interval analysis method, this paper proposes an uncertain optimization model for the ride comfort in vehicles and achieves the optimal design of vehicle ride comfort under the condition of complicated uncertainty. The spring stiffness and shock absorber damping of suspension is regarded as the design parameters, while the root mean square (RMS) of the vehicle body acceleration is treated as the design objective and the corresponding constraints are composed of suspension stiffness, natural frequency and RMS of suspension dynamic deflection. Moreover, the uncertainties of key parameters, such as sprung mass, tire stiffness, vehicle speed and road roughness, are also considered and quantified by interval analysis method. After that, an interval uncertain optimization model of vehicle suspension is established for ride comfort, which is subsequently converted to an ordinary deterministic optimization problem through a transformation model. Finally, the proposed method is applied to three typical vehicle suspension dynamic systems with two degrees of freedom, four degrees of freedom and seven degrees of freedom.