基于灵敏度分析的某商用车悬架系统参数优化

Parameter optimization of commercial vehicle suspension system based on sensitivity analysis

为提高某商用车的行驶平顺性,对某商用车悬架系统参数进行了优化.基于空气弹簧试验数据拟合得到其刚度特性曲线,建立前后悬架及整车多体动力学模型,仿真得出该车随机输入工况和脉冲输入工况平顺性.搭建悬架系统参数化的多平台联合仿真模型,通过全域灵敏度分析得出悬架系统设计参数对平顺性的影响程度.建立整车平顺性多目标响应面近似模型,利用多目标遗传优化算法进行参数可行域内寻优.结果表明:在随机输入工况下,车速为100 km/h时,驾驶员处和乘客处加权加速度均方根值分别减小了12.50%和29.71%;在脉冲输入工况下,车速为30 km/h驾驶员处和车速为20 km/h乘客处的垂向最大加速度分别减小了14.69%和31.28%,优化效果明显.

To improve the ride comfort of commercial vehicle,the parameters of the suspension system of commercial vehicle were optimized.Based on the actual test data of the air spring,the stiffness characteristic curve was fitted,and the multi-body dynamic model of the front and rear suspension and the entire vehicle was established.The smoothness of the vehicle under random input and pulse input conditions was simulated.The parametric multi-platform co-simulation model of the suspension system was built,and the degree of influence of the design parameters of the suspension system on ride comfort was obtained through the global sensitivity analysis.The multi-objective response surface approximation model for vehicle ride comfort was established,and the multi-objective genetic optimization algorithm was used to optimize the parameters in the feasible region.The results show that under the random input conditions,the root mean square(RMS)values of the weighted acceleration at the driver and passenger positions are respectively reduced by 12.50%and 29.71%when the vehicle speed is 100 km/h.Under pulse input conditions,the maximum vertical accelerations at the driver and passenger positions are respectively reduced by 14.69%and 31.28%when the vehicle speeds are respective 20 km/h and 30 km/h,and the optimization effect is obvious.