Synthesis of Double-Rocker Mechanisms for Motion Generation Using Fourier Descriptor
Dimensional synthesis of a double-rocker linkage using the discrete Fourier transform (DFT) is presented. The coupler point curve of a double-rocker linkage is open and cannot be expressed by the Fourier series with periodic coefficients. Hence, in this study, a procedure is first proposed to transform such an open curve into a closed curve such that the DFT can be applied. Subsequently, the relations between the path of a coupler point and the design parameters of linkage are established and the motion generation problem is formulated as two prescribed paths having a constant distance. Finally, a least-square based optimization scheme is used to synthesize the design parameters and two numerical examples are illustrated for the procedure.
KeywordsFourier Descriptor Discrete Fourier Transform Motion Generation Double-Rocker Mechanisms
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