汽车零部件疲劳分析载荷谱加速编辑法研究

以某试验场实车采集的轮心六分力信号和关键点监测信号为基础数据，分别采用伪损伤保留法、损伤保留法和峰谷值抽取法对实测信号加速编辑；从时间压缩比例、功率谱密度、统计参数、穿级计数和雨流计数等5个方面对加速谱进行了讨论分析；从疲劳仿真角度进一步探讨了不同加速编辑法分析零部件疲劳问题求解结果精度的差别，并对加速谱效率进行了评估。研究结果表明，3种加速编辑法分析得出的转向节疲劳寿命的相对误差差距较小，均在3.72%以内，但疲劳仿真效率较原始载荷谱有大幅提高。综合考虑多方面分析角度，损伤保留法可准确删除原始信号中的无损伤段，获取时间最短加速谱的同时功率谱密度吻合程度最好，分析零部件疲劳问题效率及分析结果的精度最高，损伤保留法相对伪损伤保留法和峰谷值抽取法更具优势。

Research on Load Spectrum Accelerated Editing Method for Fatigue Test of Vehicle Parts

Taking the wheel center six-component force signals and key point monitoring signals collected in a test field as the basic data, the pseudo-damage retention method, damage retention method and peak-valley extraction method were used to accelerate the editing of the measured signals respectively.The accelerated spectrums were discussed and analyzed from five aspects: time compression ratio, power spectral density, statistical parameters, level crossing counting and rain flow counting statistics.The accuracies from different accelerated editing methods in solving fatigue issue were further discussed by fatigue simulation, and the efficiency of accelerated spectrums was evaluated.The results show that the relative error gaps of the steering knuckle fatigue life analyzed by three accelerated editing methods are relative small, all within 3.72%, but the efficiency of fatigue simulation is much higher than original load spectrum.Taking comprehensive consideration of various aspects of analysis, the damage retention method may accurately delete the non-damaged segments in the original signals, the shortest time acceleration spectrum with the best coincidence of power spectral density will be obtained.This method has the highest efficiency in analyzing component fatigue problems and the accuracy of analysis results.The damage retention method has more advantages than the pseudo damage retention method and the peak-valley extraction method.