中文摘要：

借助傅里叶级数理论，对RCCC机构连杆曲线进行了快速傅里叶变换，得到了由谐波成分表示的任意RCCC机构连杆轨迹的数学描述。通过对其连杆轨迹谐波成分的理论分析，发现了连杆转角函数谐波特征参数与机构尺寸参数的内在联系，进而确定了机构的基本尺寸型。推导出了机构实际安装尺寸、连杆上点的位置和机构实际尺寸参数的计算公式。在此基础上，以曲柄摇杆为例，建立了一个含有数百万组机构基本尺寸型的连杆转角函数谐波特征参数数值图谱。利用建立起的数值图谱和推导的理论公式解决了RCCC机构的轨迹综合问题，最后给出了算例。

英文摘要：

From Fourier series theory, the mathematic representation of the coupler curves was obtained by using the fast Fourier transform （in short, FFT）. Through analyzing the harmonic component of the coupler curve of RCCC mechanism, the relationship between the harmonic component of the rotation--angle function and the dimensional type of the RCCC mechanism was discovered. The formulas which can compute the position for coupler point, real size and installing dimensions of the RCCC mechanism was deduced. Subsequently, taking the crank--rocker linkages as an example, a numerical atlas database comprising millions basic dimensional types are established. Based on the numerical atlas and the theoretical formulas, the problem of the RCCC mechanism path generation was solved. Finally, an example was given to prove it.