\documentclass{article}
\usepackage{pstricks,pst-eps,multido}
\usepackage[a4paper]{geometry}
% Mluque5130@aol.com
% 16-24 juin 2002
% disque tournant
% avec représentation des mobiles
% pour animation
% avec trajectoires
% et choix du cercle
\makeatletter
\pst@addfams{pst-disque}
\define@key[psset]{pst-disque}{radius}{\edef\psk@disquetournant@R{#1}} % en m
\define@key[psset]{pst-disque}{vitesse}{\edef\psk@disquetournant@vitesse{#1}} % vitesse circonférentielle
\define@key[psset]{pst-disque}{scale}{\edef\psk@disquetournant@scale{#1}} % echelle
\define@key[psset]{pst-disque}{date}{\edef\psk@disquetournant@date{#1}} % en s
\define@key[psset]{pst-disque}{tmax}{\edef\psk@disquetournant@tmax{#1}} % en s
%
\psset{radius=.35,vitesse=7,scale=0.025,date=0.5,tmax=0.6}
%
\newif\ifPst@Volant@Circles
\define@key[psset]{pst-disque}{circles}{\@nameuse{Pst@Volant@Circles#1}}%
%
%
\newif\ifPst@Volant@Construction
\define@key[psset]{pst-disque}{construction}{\@nameuse{Pst@Volant@Construction#1}}%
%
\newif\ifPst@Volant@trajectoires
\define@key[psset]{pst-disque}{trajectoires}{\@nameuse{Pst@Volant@trajectoires#1}}%
%
\newif\ifPst@Volant@disque
\define@key[psset]{pst-disque}{disque}{\@nameuse{Pst@Volant@disque#1}}%
%
\psset{circles=true,construction=false,trajectoires=false,disque=true}
%
\def\variables{%
 -100 0 translate
 /V \psk@disquetournant@vitesse\space def
 /R \psk@disquetournant@R\space def
 /reduction {\psk@disquetournant@scale\space mul} def
 /date \psk@disquetournant@date\space def
 /g 9.81 def % pesanteur
 /VitesseAngulaire V R div 180 mul 3.1459 div def
 /tmax \psk@disquetournant@tmax\space def
 /NumberTimes tmax 0.1 div cvi def
 }

\def\PSTvolant{\pst@object{PSTvolant}}
\def\PSTvolant@i{%
\pst@killglue
  \begingroup%
  \use@par%
\begin@OpenObj
\addto@pscode{%
\variables
/CLIP { newpath 0.1 2845 mul 100 add 0.06 2845 mul moveto
        0.1 2845 mul 100 add -0.01 2845 mul lineto
        -0.07 2845 mul 100 add -0.01 2845 mul lineto
        -0.07 2845 mul 100 add 0.06 2845 mul lineto
        closepath
        } def
CLIP clip
newpath
\ifPst@Volant@trajectoires
 % trace des trajectoires
 0 30 330 { % points sur le disque
 /Theta exch def
 /color Theta 360 div def
 /cosT Theta cos def
 /sinT Theta sin def
 % position initiale
 /Xi R sinT mul neg 2845 mul reduction def
 /Yi R cosT mul neg 2845 mul reduction def
 Xi Yi moveto
 % les points de la trajectoire
 0 0.01 tmax { /time exch def % dates en secondes
          % position des points
          /Xc R sinT mul neg V 1 cosT sub mul time mul add def
          /Yc R cosT mul neg
           V sinT mul time mul add
          g time dup mul mul 2 div sub
          def
          /Xpt Xc 2845 mul reduction def
          /Ypt Yc 2845 mul reduction def
          Xpt Ypt
  lineto
  } for
  0.5 setlinewidth
  1 0 1 setrgbcolor
 stroke
 } for
\fi
 % fin du dessin des trajectoires
 % boucle sur l'ensemble des points choisis sur le volant
 % pour marquer le place des points à la date choisie
 1 setlinewidth
 -30 30 330 { % points sur le disque
 /Theta exch def
 /color Theta 360 div def
 /cosT Theta cos def
 /sinT Theta sin def
 /Xinitial R sinT mul neg 2845 mul reduction def% x position initiale en pts
 /Yinitial R cosT mul neg 2845 mul reduction def % y position initiale en pts
   /Xc R sinT mul neg V 1 cosT sub mul date mul add def
   /Yc R cosT mul neg
        V sinT mul date mul add
        g date dup mul mul 2 div sub
   def
  /Xpt Xc 2845 mul reduction def
  /Ypt Yc 2845 mul reduction def
 % Xpt Ypt lineto
 gsave
 newpath
 Xpt Ypt 1.5 0 360 arc
 color 1 1 sethsbcolor
 fill % closepath
 grestore
 \ifPst@Volant@Construction
    /Yv Yc g date dup mul mul 2 div add def
    /Yvpt Yv 2845 mul reduction def
    0 setgray
    0.5 setlinewidth
    Xinitial
    Yinitial
    moveto
    Xpt Yvpt lineto
    Xpt Ypt lineto
    stroke
 \fi
 % dessin du velo
 /velo{ %
  /LaRoue {
   0 setgray
  2 setlinewidth
  V date mul 2845 mul reduction 0 R 2845 mul reduction 0 360 arc
  stroke
  newpath
  1 setgray
  V date mul 2845 mul reduction 0 4 0 360 arc
  % closepath
  fill
  0 setgray
  V date mul 2845 mul reduction 0 4 0 360 arc
  stroke }
  def
   % lesrayons
 /HUE 0 def
 0 30 330 {
 /Angle exch def
 /AnglePt Angle
    VitesseAngulaire date mul add
     def
 /abscissePtDisque
    AnglePt sin R mul neg
     V date mul add 2845 mul reduction
    def
 /ordonneeePtDisque
    AnglePt cos R mul neg
    2845 mul reduction def
 1 setlinewidth
 V date mul 2845 mul reduction 0 moveto
 abscissePtDisque ordonneeePtDisque lineto
 /HUE Angle 360 div def
 HUE 1 1 sethsbcolor
 stroke
 LaRoue
 } for
 }
 def
 } for
 % le sol
 \ifPst@Volant@disque
 %%%%%
 /unit R 2845 mul reduction def
 gsave
  velo
  unit 3 mul 0 translate
 velo
  stroke
 grestore
 gsave
 2 setlinewidth
 1 setlinejoin
 V date mul 2845 mul reduction 0 translate
 gsave
 0 0 moveto
 1.5 unit mul 0 lineto
 2 3 div unit mul 4 3 div unit mul lineto
 closepath
 stroke
 grestore
 gsave
 1.5 unit mul 0 5 0 360 arc
 1.5 unit mul 0 moveto
 2 unit mul 4 3 div unit mul lineto
 3 unit mul 0 lineto
 stroke
 grestore
 gsave
 2 unit mul 4 3 div unit mul moveto
 2 3 div unit mul 4 3 div unit mul lineto
 2 unit mul 4 3 div unit mul moveto
 2 unit mul 5 3 div unit mul lineto
 2 unit mul 2 unit mul 1 3 div unit mul -90 90 arc
 2 unit mul 2 unit mul 1 3 div unit mul add moveto
 1.6 unit mul 2 unit mul 1 3 div unit mul add lineto
 stroke
 grestore
 % selle
 newpath
 2 3 div unit mul 4 3 div unit mul moveto
 unit 5 3 div unit mul lineto
 0.3 unit mul 5 3 div unit mul lineto
 0.3 unit mul 4 3 div unit mul lineto
 closepath
  fill
 \fi
 newpath
 -100  R 2845 mul reduction neg moveto
 300 R 2845 mul reduction neg lineto
 300 R 2845 mul reduction neg -20 add lineto
 -100 R 2845 mul reduction neg -20 add lineto
 closepath
 1 setgray
 fill
 -100  R 2845 mul reduction neg moveto
 400 R 2845 mul reduction neg lineto
 2 setlinewidth
 0 setgray
 stroke
 }% fin du code ps
 \end@OpenObj
 \endgroup%
 }% % fin de la commande PSTricks
% les cercles, l'enveloppe et la parabole de sécurité

\def\PSTvolantEnveloppe{\pst@object{PSTvolantEnveloppe}}
\def\PSTvolantEnveloppe@i{%
\pst@killglue
  \begingroup%
  \use@par%
\begin@OpenObj
\addto@pscode{%
\variables
 /Helvetica
 findfont 8 scalefont setfont
 /Chaine 7 string def
 /Affiche
    { Chaine cvs show } def
 % dessin des cercles à différentes dates
 \ifPst@Volant@Circles
 0 .1 tmax { % dates en secondes
 /temps exch def
 /Ycentre g temps dup mul 2 div mul neg def
 /rayon R dup mul V dup mul temps dup mul mul add sqrt def
 0 Ycentre 2845 mul reduction rayon 2845 mul reduction 0 360 arc
 stroke
 gsave
 0 Ycentre 2845 mul reduction rayon 2845 mul reduction sub moveto
 (t = ) show
 temps Affiche
 grestore
 } for
 \else
 /Ycentre g date dup mul 2 div mul neg def
 /rayon R dup mul V dup mul date dup mul mul add sqrt def
 gsave
 0 0 1 setrgbcolor
 0.5 setlinewidth
 0 Ycentre 2845 mul reduction rayon 2845 mul reduction 0 360 arc
 stroke
 0 1 1 setrgbcolor
 0 0 rayon 2845 mul reduction 0 360 arc
 stroke
 grestore
 gsave
 % on place la date correspondant à ce cercle
 0 Ycentre 2845 mul reduction rayon 2845 mul reduction sub moveto
 (t = ) show
 date Affiche
 grestore
 \fi
}%
\end@OpenObj
 \endgroup%
 }

 \makeatother
% Denis Girou
\newcommand{\pssave}[2]{\PSTtoEPS[headers=all,bburx=10cm,bbury=6cm,bbllx=-7cm,bblly=-1cm]{#1.eps}{#2}}
%
\pagestyle{empty}
\newcount\It
\begin{document}
\psset{disque=false}
\multido{\i=1+1}{30}{%
\It=\i
  \ifnum\multidocount<10
    \def\Pad{0}%
  \else
    \def\Pad{}%
  \fi
\pssave{cyliste\Pad\the\multidocount}{%
\multido{\rdate=0.00+0.025}{\i}{%
\ifnum\multidocount=\It\psset{disque=true}\fi
\PSTvolant[vitesse=5,date=\rdate]}}}
\end{document}
