小圆圈上的箭头

Question

我想在小圆圈上画箭头。“装饰”方法对大圆圈很有效，但以下

  \begin{tikzpicture}[scale=0.5,
    decoration={markings, 
      mark= at position 0.75 with {\arrow{Stealth[width=2pt,length=3pt]}}}]
    \foreach \t in {0,...,7} {
      \draw[postaction={decorate}] (0,0) circle ({\t/5});
    }
  \end{tikzpicture}

生产

当圆圈变小时，情况就不太好了。我想我应该平移或旋转箭头。有没有简单的方法可以做到这一点？

Answer 1

\documentclass[tikz, border=1cm]{standalone}
\usetikzlibrary{arrows.meta, bending}
\begin{document}
\begin{tikzpicture}
\foreach \t in {1,...,7}
\draw[thick, -{Stealth[width=3pt, length=4pt, red]}] (-180:\t/5) arc[start angle=-180, delta angle=450, radius={\t/5}];
\end{tikzpicture}
\end{document}

编辑：这是bend建议的选项。请注意，这会使箭头本身变形。

\documentclass[tikz, border=1cm]{standalone}
\usetikzlibrary{arrows.meta, bending}
\begin{document}
\begin{tikzpicture}
\foreach \t in {1,...,7}
\draw[thick, -{Stealth[width=3pt, length=4pt, red, bend]}] (-180:\t/5) arc[start angle=-180, delta angle=450, radius={\t/5}];
\end{tikzpicture}
\end{document}

Answer 2

像这样：

代码：

\documentclass{article}
\usepackage{tikz}

\begin{document}    
    \begin{tikzpicture}[scale=1.5]
        \foreach \r in {.4,.6,...,1.1}{
            \draw[-stealth,line width=3pt] (0:\r) arc(0:270:\r) ;
            \draw[line width=3pt] (270:\r) arc(270:360:\r);
        }
    \end{tikzpicture}
\end{document}