油气悬架的不确定性多目标优化

Multi-objective Optimization Based on Uncertainty in Hydro-pneumatic Suspension

为改善某393t矿用自卸车的平顺性能,需要优化油气悬架的非线性刚度阻尼特性,建立了更符合工程实际情况的7自由度整车模型.考虑矿用车运输过程中整车质量与质心位置的不确定性,选取对目标函数影响较大的悬架刚度和阻尼系数作为设计变量,选取整车质心加速度和车身侧倾角、车身俯仰角以及悬架的动扰度和车轮的动载荷作为目标函数,利用基于薄板样条插值的高维模型(TPS-HDMR)构建设计变量与目标函数之间的近似模型.采用基于Pareto概念的多目标优化遗传算法进行优化,得到了最优Pareto解集.仿真结果表明:多目标优化可以同时改善11个目标的性能,提高汽车的平顺性.

In order to optimize the ride comfort of mining dump trucks of 3 9 3 tons in bad driving traf-fic,the nonlinear stiffness and damping characteristics of hydro-pneumatic suspension were optimized.A 7-DOF full model,more realistic than traditional vehicle models,was derived.And considering the uncer-tainty of mass and position of centroid in the process of transportation,some factors of stiffness and damp-ing of suspension having greater influence on target were selected as the design variables.The target func-tion contains the body＇s vertical acceleration,roll angular acceleration,pitch angular acceleration,dynamic displacement of suspension and dynamic load of the wheel.An approximate model between design variables and objective function was established by High Dimensional Model Representation based on Thin Plate Spline Interpolation （TPS-HDMR）.This model adopts multi-obj ective optimization with genetic algorithm based on the concept of Pareto,and then gets the Pareto optimal solution set.The simulation results have shown that multi-obj ective optimization can improve the performance of 1 1 targets and ride comfort.