statefeed6
\documentclass{standalone} \usepackage{tikz} \usetikzlibrary{shapes,positioning} \usetikzlibrary{narrow} % The double arrow comes from % http://www.texample.net/tikz/examples/double-arrows/ % with modification in % http://tex.stackexchange.com/questions/169061/tikz-increase-arrow-head-size \usetikzlibrary{arrows,decorations.markings} \tikzset{block/.style={draw, rectangle, line width=2pt, fill=blue!10, minimum height=3em, minimum width=3em, outer sep=0pt}} \tikzset{sumcircle/.style={draw, circle, outer sep=0pt, label=center:{{$\sum$}}, minimum width=2em}} \tikzset{vecArrow/.style={ line width=1pt, decoration={ markings,mark=at position 1 with { \arrow[scale=2.5,line width=0.4pt] {open triangle 60} } }, double distance=4pt, shorten >= 13pt, preaction = {decorate}, postaction = {draw,line width=4pt, white,shorten >= 10pt} }} \tikzset{innerWhite/.style={semithick, white, line width=1.4pt, shorten >= 4.5pt}} \tikzset{every picture/.style={auto, line width=1pt, >=narrow, x=1mm, y=1mm, font=\small}} \begin{document} \begin{tikzpicture} \node[sumcircle](sumA){}; \node[block,right=20mm of sumA](Adam){Adam}; \coordinate[right=15mm of Adam](output); \node[block,below=5mm of Adam](Bertil){Bertil}; \node[block,left=10mm of sumA](Cesar){Cesar}; \node[block, below=20mm of sumA,xshift=16mm](David){David}; \node[block, below=20mm of sumA,xshift=-16mm](Erik){Erik}; \node[block, left=10mm of Erik](Filip){Filip}; \node[sumcircle, left=10mm of Filip](sumB){}; \node[block,below=35mm of sumA](Gustaf){Gustaf}; \coordinate[left=40mm of Cesar](Input){}; \draw[->](Input)--node{$a$}(Cesar); \draw[->](Cesar-|sumB)--(sumB); \draw[->](sumB)--node[xshift=-1mm]{$d$}(Filip); \draw[->](Filip)--node[xshift=-1mm]{$e$}(Erik); \draw[->](Cesar)--(sumA); \draw[->](sumA)--node(forkB){$b$}(Adam); \draw[->](forkB)|-(Bertil); \draw[->](Adam)--node(C){$c$}(output); \draw[->](C)|-(Gustaf); \draw[->](C)|-(Bertil); \draw[->](Gustaf)-|(sumB); \draw[vecArrow](Bertil)|-node[xshift=3mm,yshift=8mm]{$x$}(David); \coordinate[right=5mm of Erik](ER); \draw[->](Erik)--(ER)--(sumA); \coordinate[left=5mm of David](DL); \draw[->](David)--(DL)--(sumA); \end{tikzpicture} \end{document}