摘要
考虑机械零件参数随时间的演化,基于伊藤引理(Ito’s lemma),推导建立了挂车车架时变不确定性可靠度计算模型。将时变不确定性由时变参数的漂移率和波动率决定,解析了车架时变不确定性计算的原理。与传统方法相比,该模型算得的车架可靠度是动态的,可以预测未来任意时刻的可靠度,从而为零件的未来发展趋势提供先期预警,为设备维护提供指导。
Considering the evolution of mechanical part's parameters and based on the Ito's lemma,a time-varying uncertainty reliability calculation model of trailer's frame was established.In this model, the frame's time-varying uncertainty could be expressed by drift rate and volatility rate.Thus the principle of time-varying uncertainty calculation for frame was expounded.Compared with the traditional methods,this method can obtain the dynamic reliability of frame,and the reliability at any time in the future can be calculated.This model can forecast the part's future development trend and offer early warnings,giving proper advice for the equipment maintenance.
引文
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