中文摘要：

以某液压挖掘机工作装置为研究对象，在对动臂油缸、铲斗油缸、斗杆油缸等工作油缸进行频响函数测量的基础上，运用时域卷积法对所测频响函数进行了希尔伯特变换，得到了工作油缸存在着非线性性质的结论，为指导动力学模型的建立提供了参考。

英文摘要：

The work device of hydraulic excavator is considered as investigation object. The Hilbert transformation of the frequency response functions which measured by experiment modal is carried out by the means of time domain convolution. The conclusions can been drawn that the cylinder dynamic behavior is nonlinear, on the basis of Hilbert transformation. The results are made reference to bulit dynamic model.