如果块中的文本“吹出”了它并且它的尺寸开始干扰其他块，那么如何进行自动对齐？
\documentclass[tikz,a4paper,border=1mm]{standalone}
\usepackage{pgfplots}
\usepackage{amsmath}
\usetikzlibrary{positioning,arrows}
\begin{document}
\tikzset{%
block/.style={draw, fill=white, rectangle,
minimum height=2em, minimum width=3em},
input/.style={inner sep=0pt},
output/.style={inner sep=0pt},
sum/.style = {draw, fill=white, circle, minimum size=2mm, node distance=1.5cm, inner sep=0pt},
pinstyle/.style = {pin edge={to-,thin,black}}
}
\begin{tikzpicture}[auto, node distance=2cm, on grid, >=latex']
\node[input] (input) {};
\node[input, above = of input] (input1) {};
\node [sum, right = of input] (sum) {};
\node [block, right = of sum] (controller) {$K(s)$};
\node [block, right = of controller] (filterinv) {$H^{-1}(s)$};
\node [block, right = 2.5cm of filterinv] (system) {$\begin{cases} 3x + 5y + z \\ 7x – 2y + 4z \\ -6x + 3y + 2z \end{cases}$};
\node [output, right = of system] (output) {};
\node [output, above = of output] (output1) {};
\node [block, below = of filterinv] (filter) {$H(s)$};
\draw [draw,->] (input) node[above right] {$s_{i-1}$} -- (sum);
\draw [->] (sum) -- node {$e_{i}$} (controller);
\draw [->] (controller) -- node[name=xi] {$\xi_{i}$} (filterinv);
\draw [->] (filterinv) -- node[name=u, pos=.3] {$u_{i}$} (system);
\draw [->] (system) -- (output) node [name=q, above left] {$q_{i}$};
\draw [->] ([xshift=-5mm]q.south) |- (filter);
\draw [->] (filter) -| node[pos=0.99, right] {$-$}
node [pos=.25, above] {} (sum);
\draw [->] (u.east|-system) |-
(output1) node[above left] (ui) {$u_i$};
\end{tikzpicture}
\end{document}
编辑：
\documentclass[tikz,a4paper,border=1mm]{standalone}
\usepackage{pgfplots}
\usepackage{amsmath}
\usetikzlibrary{positioning,arrows}
\begin{document}
\tikzset{%
block/.style={draw, fill=white, rectangle,
minimum height=2em, minimum width=3em},
input/.style={inner sep=0pt},
output/.style={inner sep=0pt},
sum/.style = {draw, fill=white, circle, minimum size=2mm, node distance=1.5cm, inner sep=0pt},
pinstyle/.style = {pin edge={to-,thin,black}}
}
\begin{tikzpicture}[auto, node distance=1cm, >=latex']
\node[input] (input) {};
\node[input, above = of input] (input1) {};
\node [sum, right = of input] (sum) {};
\node [block, right = of sum] (system) {$\begin{cases} \dot{\vec{x}}_i=f_i(\vec{x}_i,t)+g_i(\vec{x}_i,t)u(t) \\ y=h_i(\vec{x}_i,t)\end{cases}$};
\node [output, right = of system] (output) {};
\node [output, above = of output] (output1) {};
\node [block, below = of system] (controller) {$K(s)$};
\draw [draw,->] (input) node[above right] {$0$} -- (sum);
\draw [->] (sum) -- node {$e_{i}$} (system);
\draw [->] (system) -- (output) node [name=q, above left] {$y$};
\draw [->] ([xshift=-5mm]q.south) |- node {$x$} (controller);
\draw [->] (controller) -| node[pos=0.99, right] {$-$}
node [pos=.25, above] {$s$} (sum);
\end{tikzpicture}
\end{document}
如何添加$x$从节点开始$K(s)$并将点添加到节点？
答案1
通过使用chains主分支上的节点库，您将不会遇到节点之间等距间距的问题：
\documentclass[preview, border=3.141592mm]{standalone}
\usepackage{tikz}
\usetikzlibrary{arrows.meta,
chains,
positioning,
quotes}
\tikzset{cntrl/.style = {
> = Stealth,
node distance = 4mm and 8mm,
box/.style = {draw, minimum size=7mm},
C/.style = {circle, draw, minimum size=4mm},
dot/.style = {circle, fill, inner sep=2pt},
every edge/.append style = {draw, ->},
start chain
} }
\usepackage{amsmath}
\begin{document}
First image:
\begin{tikzpicture}[cntrl]
\begin{scope}[nodes={on chain=going right}]
\coordinate (in) {};
\node (sum) [C] {};
\node (controller)[box] {$K(s)$};
\node (filterinv) [box] {$H^{-1}(s)$};
\node (aux1) [dot] {};
\node (system) [box] {$\begin{cases}
3x + 5y + z \\
7x – 2y + 4z \\
-6x + 3y + 2z
\end{cases}$};
\node (aux2) [dot] {};
\coordinate (out);
\end{scope}
\coordinate[above=of system.north -| out] (ui);
\node(filter) [box, below=of filterinv] {$H(s)$};
%
\draw (in) edge["$s_{i-1}$"] (sum)
(sum) edge["$e_{i}$"] (controller)
(controller)edge["$\xi_{i}$"] (filterinv)
(filterinv) edge[pos=0.25, "$u_{i}$"] (system)
(system) edge[pos=0.75, "$q_{i}$"] (out);
\draw[->] (aux1) |- (ui) node[above left] {$u_i$};
%
\draw[->] (aux2) |- (filter.east) node[above right] {$x$};
\draw[->] (filter) -| (sum) node[below right] {$-$};
\end{tikzpicture}
Second image:
\begin{tikzpicture}[cntrl]
\begin{scope}[nodes={on chain=going right}]
\coordinate (in) {};
\node (sum) [C] {};
\node (system) [box] {$\begin{cases}
\dot{\vec{x}}_i = f_i(\vec{x}_i,t)+g_i(\vec{x}_i,t)u(t) \\
y = h_i(\vec{x}_i,t)
\end{cases}$};
\node (dot) [dot] {};
\coordinate (out);
\end{scope}
\node(filter) [box, below=of system] {$K(s)$};
%
\draw (in) edge["$s_{i-1}$"] (sum)
(sum) edge["$e_{i}$"] (system)
(system) edge[pos=0.25, "$q_{i}$"] (out);
%
\draw[->] (dot) |- (filter.east) node[above right] {$x$};
\draw[->] (filter) -| (sum) node[pos=0.25,above] {$s$}
node[below right] {$-$};
\end{tikzpicture}
\end{document}
答案2
我会放弃该on grid选项，稍微减少节点距离，并移除节点的额外移位(system)。但是，如果您的图表更复杂，您可能需要手动移动节点。
\documentclass[tikz,a4paper,border=1mm]{standalone}
\usepackage{pgfplots}
\usepackage{amsmath}
\usetikzlibrary{positioning,arrows}
\begin{document}
\tikzset{%
block/.style={draw, fill=white, rectangle,
minimum height=2em, minimum width=3em},
input/.style={inner sep=0pt},
output/.style={inner sep=0pt},
sum/.style = {draw, fill=white, circle, minimum size=2mm, node distance=1.5cm, inner sep=0pt},
pinstyle/.style = {pin edge={to-,thin,black}}
}
\begin{tikzpicture}[auto, node distance=1cm, >=latex']
\node[input] (input) {};
\node[input, above = of input] (input1) {};
\node [sum, right = of input] (sum) {};
\node [block, right = of sum] (controller) {$K(s)$};
\node [block, right = of controller] (filterinv) {$H^{-1}(s)$};
\node [block, right = of filterinv] (system) {$\begin{cases} 3x + 5y + z \\ 7x – 2y + 4z \\ -6x + 3y + 2z \end{cases}$};
\node [output, right = of system] (output) {};
\node [output, above = of output] (output1) {};
\node [block, below = of filterinv] (filter) {$H(s)$};
\draw [draw,->] (input) node[above right] {$s_{i-1}$} -- (sum);
\draw [->] (sum) -- node {$e_{i}$} (controller);
\draw [->] (controller) -- node[name=xi] {$\xi_{i}$} (filterinv);
\draw [->] (filterinv) -- node[name=u, pos=.3] {$u_{i}$} (system);
\draw [->] (system) -- (output) node [name=q, above left] {$q_{i}$};
\draw [->] ([xshift=-5mm]q.south) |- (filter);
\draw [->] (filter) -| node[pos=0.99, right] {$-$}
node [pos=.25, above] {} (sum);
\draw [->] (u.east|-system) |-
(output1) node[above left] (ui) {$u_i$};
\end{tikzpicture}
\end{document}
考虑到OP的编辑：
\documentclass[tikz,a4paper,border=1mm]{standalone}
\usepackage{pgfplots}
\usepackage{amsmath}
\usetikzlibrary{positioning,arrows}
\begin{document}
\tikzset{%
block/.style={draw, fill=white, rectangle,
minimum height=2em, minimum width=3em},
input/.style={inner sep=0pt},
output/.style={inner sep=0pt},
sum/.style = {draw, fill=white, circle, minimum size=2mm, node distance=1.5cm, inner sep=0pt},
pinstyle/.style = {pin edge={to-,thin,black}}
}
\begin{tikzpicture}[auto, node distance=1cm, >=latex']
\node[input] (input) {};
\node [sum, right = of input] (sum) {};
\node [block, right = of sum] (system) {$\begin{cases} \dot{\vec{x}}_i=f_i(\vec{x}_i,t)+g_i(\vec{x}_i,t)u(t) \\ y=h_i(\vec{x}_i,t)\end{cases}$};
\node [sum, right = of system] (sum2) {};
\node [output, right = of sum2] (output) {};
\node [block, below = of system] (controller) {$K(s)$};
\draw [draw,->] (input) node[above right] {$0$} -- (sum);
\draw [->] (sum) -- node {$e_{i}$} (system);
\draw (system) -- (sum2);
\draw [->] (sum2) -- (output) node [name=q, above left] {$y$};
\draw [->] (sum2) |- node[pos=.75, above] {$x$} (controller);
\draw [->] (controller) -| node[pos=0.99, right] {$-$} node [pos=.25, above] {$s$} (sum);
\end{tikzpicture}
\end{document}
考虑到 OP 的补充评论（抱歉，我无法准确读懂所使用的符号）：
\documentclass[tikz,a4paper,border=1mm]{standalone}
\usepackage{pgfplots}
\usepackage{amsmath}
\usetikzlibrary{positioning,arrows}
\begin{document}
\tikzset{%
block/.style={draw, fill=white, rectangle,
minimum height=2em, minimum width=3em},
input/.style={inner sep=0pt},
output/.style={inner sep=0pt},
sum/.style = {draw, fill=white, circle, minimum size=2mm, node distance=1.5cm, inner sep=0pt},
pinstyle/.style = {pin edge={to-,thin,black}}
}
\begin{tikzpicture}[auto, node distance=1cm, >=latex']
\node[input] (input) {};
\node [sum, right = of input] (sum) {};
\node [block, right = of sum] (system1) {$ \alpha(\zeta, x) + \beta(\zeta, x)w $};
\node [block, above = of system1] (system2) {$ \dot{\zeta} = A\zeta + Bw $};
\node [block, right = of system1] (system3) {$ \begin{aligned} \dot{x} &= f(x) + g(x)u \\ \dot{y} &= h(x) \end{aligned} $};
\node [output, right = of system3] (output) {};
\draw [draw,->] (input) node[above right] {$w$} -- (sum);
\draw [->] (sum) -- (system1);
\draw [->] (sum) |- (system2);
\draw [->] (system2) -- node[right] {$\zeta$} (system1);
\draw [->] (system1) -- node[above] {$u$} (system3);
\draw [->] (system3) -- (output) node [above left] {$y$};
\draw [->] (system3) |- ++(0,-1) -| (system1) node [right, pos=.75] {$x$};
\end{tikzpicture}
\end{document}
