\documentclass[tikz]{standalone}\input{pre.tex}\begin{document}\begin{tikzpicture}
\draw[draw=none, use as bounding box] (-5mm,-5mm) rectangle (5mm,5mm);
\def\iangle{-10};
\def\rule{35mm};
% \draw[axis, opacity=0.5] (-20mm,0) -- (20mm,0);
\coordinate (0) at (0,0);
% \draw[axis, line width = 0.3pt, ->] (-10mm, -12.5mm) -- ++(20mm, -0mm) node[right, scale=0.8]{$y$};
% \draw[axis, line width = 0.3pt, ->, color=black!30] (0, -12.5mm) -- ++ (0, -30mm) node[below, scale=0.8, black]{$x$};
\draw[interface] (-30mm,-50mm) rectangle ++(60mm,-2mm);
\draw[thin, black!50] (-30mm,-50mm) -- ++(60mm,0);
\foreach \x in {0,90,...,270} {
\draw[line width=8mm/10, color=black!10] (0) -- +({\x+\iangle}:{395mm/10/2});
\draw[line width=13.5mm/10, color=black!20] (0) -- +({\x+\iangle}:{6.3mm/10+42mm/10/2});
\draw[line width={31.5mm/10/2}, color=black!20] ($(0)+({\x+\iangle}:{6.3mm/10+42mm/10/2+5mm})$) -- +({\x+\iangle}:{25mm/10});
}%
\draw[black!80,thin] ($(0)+(35mm/10/2,0)$) -- ++ (0,-30mm);
% \draw[color=black!15, fill=black!10] ($(0)+(31.5mm/10/2,0)+(-1mm,-30mm)$) rectangle ++(2mm,-6mm);
\node[fill=black!10, draw=black!20] (rect) at ($(0)+(35mm/10/2,0)-(0,30mm)$) [draw,thick,minimum width=1mm,minimum height=5mm] {};
% \draw[fill=white] (0) circle (42mm/10/2);
\draw[fill=white] (0) circle (35mm/10/2);
\draw[fill=black!10] (0) circle (24mm/10/2);
\draw[fill=black!30] (0) circle (10mm/10/2);
% \draw[axis, black, ->] (0) -- ++(\iangle:20mm) node[below, scale=0.8]{$\tau$};
\draw[solid,shorten >=0.5pt, ->] (0)++(1.6cm,0) arc(0:\iangle:1.6cm);
\node[color=black, scale=0.8] at ($(0)+(\iangle/2:1.8)$) {$\phi$};
\draw (3mm,3mm) node [scale=0.3, blue] {$\bigotimes\vec\omega$};
\draw[->, blue] (0, 0.5mm) -- ++(-3.2mm,0) node[left, scale=0.3] {$\vec{f}_R$};
\draw[->, blue] ($(0)+(35mm/10/2,0)$) -- ++ (0,-4mm) node[right, scale=0.3] {$\vec{T}'$};
\draw (-3mm,3mm) node [scale=0.3, magenta] {$\bigodot\vec{M}_R$};
\draw (-3mm,-3mm) node [scale=0.3, magenta] {$\bigotimes\vec{M}_T$};
\end{tikzpicture}\end{document}
