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我如何在机械原理图中绘制 Circuitikz 风格的非线性弹簧？

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我如何在机械原理图中绘制 Circuitikz 风格的非线性弹簧？

circuitikz 包提供了一种在机械电路中绘制线性弹簧（具有恒定刚度的弹簧）的简单方法。我想以类似 circuitikz 的方式绘制非线性弹簧（其刚度会随着拉伸而变化），但 circuitikz 没有提供非线性弹簧的符号。我该怎么做？

期望输出

我希望这个符号看起来像一个线圈间距不均匀的弹簧：

所需的非线性弹簧符号

最小工作示例

该代码将生成线性弹簧符号。

\documentclass{standalone}
\usepackage{circuitikz}
\begin{document}
  \begin{circuitikz}
    \draw (0,0) to [spring] (0, 2);
  \end{circuitikz}
\end{document}

最小工作示例代码的输出

答案1

我制作了一个不太笨拙的版本，其中您可以使用一个键factor来设置弹簧与中心的偏离程度，在此过程中，我最终可以轻松更改弹簧中的线圈数量，因此我添加了一个coils键来更改它。 的默认值为factor，0因此行为与原始 相同，的spring默认值为，与原始 相同。coils4

现在你可以将它用于：

\draw (0,0) to [ravenspring={factor=2,coils=4}] (0, 2);

不改变任何定义。

旧答案如下，供参考。

在此处输入图片描述

代码：

\documentclass{standalone}
\usepackage{circuitikz}
\usepackage{expl3}
\ExplSyntaxOn
\cs_new:Npn \__raven_factor:nnnn #1 #2 #3 #4
  { \fp_eval:n { #2 + #1*(#3 - (#2))/#4 } }
\cs_new:Npn \__raven_factor_half:nnnn #1 #2 #3 #4
  { \fp_eval:n { 0.5 * ( #2 + #1*(#3 - #2)/#4 ) } }
\cs_set_eq:NN \FullFactor \__raven_factor:nnnn
\cs_set_eq:NN \HalfFactor \__raven_factor_half:nnnn
\cs_set_eq:NN \IntStepVariable \int_step_variable:nnNn
\ExplSyntaxOff

\makeatletter
\ctikzset{bipoles/ravenspring/height/.initial=.5}
\ctikzset{bipoles/ravenspring/width/.initial=.5}
\ctikzset{bipoles/ravenspring/factor/.initial=0}
\ctikzset{bipoles/ravenspring/coils/.initial=4}
\def\pgf@circ@ravenspring@path#1{\pgf@circ@bipole@path{ravenspring}{#1}}
\compattikzset{%
  ravenspring/.code = {%
    \ctikzset{\circuitikzbasekey,/tikz/to path=\pgf@circ@ravenspring@path}%
    \ctikzset{\circuitikzbasekey/bipoles/ravenspring/.cd,#1}
  }
}

\pgfcircdeclarebipole{}
  {\ctikzvalof{bipoles/ravenspring/height}}
  {ravenspring}
  {\ctikzvalof{bipoles/ravenspring/height}}
  {\ctikzvalof{bipoles/ravenspring/width}}
  {%
    \pgfsetlinewidth{\pgfkeysvalueof{/tikz/circuitikz/bipoles/thickness}\pgfstartlinewidth}
    \pgftransformationadjustments

    \edef\raven@coils{\number\numexpr\ctikzvalof{bipoles/ravenspring/coils}*2+1}
    \pgfmathsetlength{\pgf@circ@res@step}
    {(\ctikzvalof{bipoles/ravenspring/width}*\pgf@circ@Rlen+\pgfhorizontaltransformationadjustment*.5*\pgflinewidth)/(\raven@coils-1)/2}

    \pgfpathmoveto{\pgfpoint{\pgf@circ@res@left-\pgfhorizontaltransformationadjustment*0.5*\pgflinewidth}{\pgf@circ@res@zero}}
    \pgfsetcornersarced{\pgfpoint{.5\pgf@circ@res@up}{.5\pgf@circ@res@up}}
    \pgf@circ@res@other = \pgf@circ@res@left
    \edef\raven@factor{\ctikzvalof{bipoles/ravenspring/factor}}
    \IntStepVariable {1} {\raven@coils} \raven@coil
      {%
        \advance\pgf@circ@res@other by
        \ifnum
          \ifnum\raven@coil=1\space 1\else 0\fi
          \ifnum\raven@coil=\raven@coils\space 1\else 0\fi
          =0
          \expandafter\FullFactor
        \else
          \expandafter\HalfFactor
        \fi
          {\raven@coil}{2-\raven@factor}{2+\raven@factor}{\raven@coils}\pgf@circ@res@step
        \ifnum \raven@coil=\raven@coils
          \let\raven@moveto\pgf@circ@res@zero
        \else
          \ifodd\raven@coil
            \let\raven@moveto\pgf@circ@res@up
          \else
            \let\raven@moveto\pgf@circ@res@down
          \fi
        \fi
        \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\raven@moveto}}
      }
    \pgfsetbuttcap
    \pgfsetbeveljoin
    \pgfusepath{stroke}
  }
\makeatother

\begin{document}
  \begin{circuitikz}
    \draw (0,0) to [ravenspring={factor=2,coils=4}] (0, 2);
  \end{circuitikz}
  \begin{circuitikz}
    \draw (0,0) to [ravenspring={factor=3,coils=6}] (0, 2);
  \end{circuitikz}
\end{document}

旧答案，手动设置因素：

我声明了一个新形状，ravenspring（如果您想重命名它，只需将所有出现的更改ravespring为您喜欢的名称）：

在此处输入图片描述

要改变弹簧每个环之间的比率，您必须改变<factor>：

\advance\pgf@circ@res@other by <factor>\pgf@circ@res@step

因此，这些因子的总和为16。如果总和不等于16，则弹簧将比可用间隙短或长。此外，第一个和最后一个因子应减半，否则弹簧的最后半圈将太长。

完整代码：

\documentclass{standalone}
\usepackage{circuitikz}

\makeatletter
\ctikzset{bipoles/ravenspring/height/.initial=.5}
\ctikzset{bipoles/ravenspring/width/.initial=.5}
\def\pgf@circ@ravenspring@path#1{\pgf@circ@bipole@path{ravenspring}{#1}}
\compattikzset{ravenspring/.style = {\circuitikzbasekey, /tikz/to path=\pgf@circ@ravenspring@path, l=#1}}
\pgfcircdeclarebipole{}
  {\ctikzvalof{bipoles/ravenspring/height}}
  {ravenspring}
  {\ctikzvalof{bipoles/ravenspring/height}}
  {\ctikzvalof{bipoles/ravenspring/width}}
  {%
    \pgfsetlinewidth{\pgfkeysvalueof{/tikz/circuitikz/bipoles/thickness}\pgfstartlinewidth}
    \pgftransformationadjustments

    \pgfmathsetlength{\pgf@circ@res@step}
    {(\ctikzvalof{bipoles/ravenspring/width}*\pgf@circ@Rlen+\pgfhorizontaltransformationadjustment*.5*\pgflinewidth)/16}

    \pgfpathmoveto{\pgfpoint{\pgf@circ@res@left-\pgfhorizontaltransformationadjustment*0.5*\pgflinewidth}{\pgf@circ@res@zero}}
    \pgfsetcornersarced{\pgfpoint{.5\pgf@circ@res@up}{.5\pgf@circ@res@up}}
    \pgf@circ@res@other = \pgf@circ@res@left
    \advance\pgf@circ@res@other by 0.50\pgf@circ@res@step
    \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@up}}
    \advance\pgf@circ@res@other by 1.25\pgf@circ@res@step 
    \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@down}}
    \advance\pgf@circ@res@other by 1.50\pgf@circ@res@step
    \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@up}}
    \advance\pgf@circ@res@other by 1.75\pgf@circ@res@step
    \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@down}}
    \advance\pgf@circ@res@other by 2.00\pgf@circ@res@step
    \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@up}}
    \advance\pgf@circ@res@other by 2.25\pgf@circ@res@step
    \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@down}}
    \advance\pgf@circ@res@other by 2.50\pgf@circ@res@step
    \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@up}}
    \advance\pgf@circ@res@other by 2.75\pgf@circ@res@step
    \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@down}}
    \advance\pgf@circ@res@other by 1.50\pgf@circ@res@step
    \pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@zero}}
    \pgfsetbuttcap
    \pgfsetbeveljoin
    \pgfusepath{stroke}
  }
\makeatother

\begin{document}
  \begin{circuitikz}
    \draw (0,0) to [ravenspring] (0, 2);
  \end{circuitikz}
\end{document}

一些变体，改变了不均匀春天的：

上面的那个：

在此处输入图片描述

<factor>s:

0.500
1.250
1.500
1.750
2.000
2.250
2.500
2.750
1.500

更加扭曲的是：

在此处输入图片描述

<factor>s:

0.250
0.875
1.250
1.625
2.000
2.375
2.750
3.125
1.750

失真程度较低：

在此处输入图片描述

<factor>s:

0.750
1.625
1.750
1.875
2.000
2.125
2.250
2.375
1.250

破碎的：

在此处输入图片描述

<factor>s:

0.000
0.500
1.000
1.500
2.000
2.500
3.000
3.500
2.000

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