\documentclass[pstricks]{standalone}
\usepackage{pst-fourbarlinkage,multido}
\begin{document}
\multido{\i=0+10}{37}{
\begin{pspicture}(-8,-8)(11,13) % class 10
\psFourBarLinkage[unit=2,barlengths=14 14 20 14,crossed,N=\i,connectedpoints,centrodes,fixedcentrodes,dmax=5,posM=0.5 2] % classe 10
\end{pspicture}}
\end{document}