Graphics, Figures & Tables ⇒ Drawing a Cogwheel

[simo]

In PSTricks its known as a cogwheel. My aim is to draw a circle with the outer border as a cogwheel and the inside border as a normal smooth curve, may be shade the area between. If I use PSTricks I'm required to use ps2pdf. But this will conflict with other parts and packages that need pdfLaTeX. An idea is appreciated.

[Stefan Kottwitz]

Hi Simo,

sounds like you could do it with a \foreach loop in TikZ. However, you could use PSTricks with pdfLaTeX when you load it with the pdf option:

Code: Select all

\usepackage[pdf]{pstricks}

Stefan

[svend_tveskaeg]

Just as a supplementation to Stefan's answer. The PSTricks wizard himself (aka. Herbert Voß) has answered a similar question on {TeX} SX.

[localghost]

[…] The PSTricks wizard himself (aka. Herbert Voß) has answered a similar question on {TeX} SX.

You can find lots of solutions for PSTricks with PDFLaTeX also here in the forum archive. And also on {TeX} SX there is a nice and simple answer to the question.


Thorsten

[Stefan Kottwitz]

Yes, there's a very nice short way created by Alain Matthes - here two stacked wheels with different parameters as a demo:

Code: Select all

\documentclass[11pt]{scrartcl}
\usepackage{tikz}

% #1 number of teeths
% #2 radius intern
% #3 radius extern
% #4 angle from start to end of the first arc
% #5 angle to decale the second arc from the first 

\newcommand{\gear}[5]{%
\foreach \i in {1,...,#1} {%
  [rotate=(\i-1)*360/#1]  (0:#2)  arc (0:#4:#2) {[rounded corners=1.5pt]
             -- (#4+#5:#3)  arc (#4+#5:360/#1-#5:#3)} --  (360/#1:#2)
}}  

\begin{document}
 \begin{tikzpicture}
   \draw[thick] \gear{18}{2}{2.4}{10}{2};
 \end{tikzpicture}  
\end{document} 

Just vary the values arguments. Just for fun with a quick shading too:

Code: Select all

\draw[shade] \gear{18}{2}{2.4}{10}{2};
\path[shade] circle(2);

wheels.png (5.66 KiB) Viewed 12125 times

Stefan

[svend_tveskaeg]

Nice. That could come in handy for me as well.

[simo]

Hey Stefan_K,

though am supposed to read on the \foreach loop in the manual, I would appreciate your explanation on the \foreach code used. It would help to learn faster.

This is good progress, I got it and this is what I have now.

Code: Select all

\documentclass{scrartcl}
\usepackage{tikz}

% #1 number of teeths
% #2 radius intern
% #3 radius extern
% #4 angle from start to end of the first arc
% #5 angle to decale the second arc from the first

\newcommand{\gear}[5]{%
  \foreach \i in {1,...,#1} {%
    [rotate=(\i-1)*360/#1]  (0:#2)  arc (0:#4:#2) {[rounded corners=.8pt]
     -- (#4+#5:#3)  arc (#4+#5:360/#1-#5:#3)} --  (360/#1:#2)
  }
}  

\begin{document}
  \begin{tikzpicture}[]
    \draw[fill=red] \gear{11}{3}{3.35}{10}{2};
    \path[fill=red] circle(3);
    \draw[thick,double distance=2pt,fill=white] circle(2.35);
  \end{tikzpicture}  
\end{document}

[svend_tveskaeg]

Maybe the package pst-spirograph (list of files) is useful. Unfortunately, it is not on CTAN.