基于实测载荷谱的某全域车悬架下控制臂疲劳寿命研究

Research on fatigue life of all-terrain vehicle control arm based on measured load spectrum

基于实测力信号载荷谱研究了某全域车悬架下控制臂疲劳寿命问题。建立下控制臂有限元模型,并通过模态试验证实了有限元模型的有效性。基于某全域车道路载荷谱采集试验,获得了悬架下控制臂力载荷信号,并对信号进行处理及分析,验证了力载荷信号的可靠性。以某全域车实际运行工况建立下控制臂边界约束,以实测力载荷信号为输入对其进行动力学仿真分析。综合动力学分析结果中的应力应变信号、修正后的局部应力应变法及兰德格拉夫损伤准则进行悬架下控制臂疲劳寿命计算,结果表明:某全域车悬架下控制臂总寿命为3.562×10^(5)km,符合设计要求,基于实际行驶载荷谱能够较为准确预估实际行驶疲劳寿命。

Based on the measured force signal load spectrum,the fatigue life of the lower control arm of a certain global vehicle suspension was studied.A finite element model of the lower control arm was established,and the validity of the finite element model was verified through modal tests.Based on the road load spectrum acquisition test of a certain global vehicle,the force load signal of the lower control arm of the suspension was obtained,and the signal was processed and analyzed to verify the reliability of the force load signal.The boundary constraint of the lower control arm was established based on the actual operating conditions of a certain global vehicle,and its dynamics simulation analysis was carried out with the measured force and load signal as the input.The stress-strain signal in the dynamic analysis results,the modified local stress-strain method and the Landgrave damage criterion were used to calculate the fatigue life of the lower control arm of the suspension.The results show that the total life of the lower control arm of a global vehicle suspension is 3.562×10^(5) kilometers,which meets the design requirements,and can more accurately predict the actual driving fatigue life based on the actual driving load spectrum.