%&tex
\documentclass{standalone}
\usepackage{tikz}
\usepackage{siltex}
\usetikzlibrary {arrows.meta,positioning}
\usetikzlibrary{calc,patterns}
\input{graphics/tics.tikz}

\begin{document}
\begin{tikzpicture}[>=Stealth, on grid, y=2.16cm, x=2.16cm]

    \draw(0,0) pic {whiteboard};
    \begin{scope}[shift={(2,2.8)}]
        \draw[fill=gray] (0,0) circle (0.2);
        \begin{scope}[rotate=-60, rounded corners]
            \draw[fill=gray!60](-0.075,-0.075) rectangle (1.5,0.075);
            \begin{scope}[shift={(0.8,0)}]
                \draw[<->] ({0.8*cos(20)},{0.8*sin(20)}) arc[start angle = 20, end angle= -20, radius = 0.8] node[midway, below right]{$\alpha$};
            \end{scope}
            \begin{scope}[shift={(1.44,0)}]
                \begin{scope}[rotate=-104]
                    \draw[fill=gray!60](-0.075,-0.075) rectangle (1.5,0.075);
                    \begin{scope}[shift={(0.8,0)}]
                        \draw[<->] ({0.8*cos(20)},{0.8*sin(20)}) arc[start angle = 20, end angle= -20, radius = 0.8] node[midway, left]{$\beta$};
                    \end{scope}
                \end{scope}
            \end{scope}
        \end{scope}
    \end{scope}
\end{tikzpicture}
\end{document}