Message Boards Message Boards

0
|
19431 Views
|
1 Reply
|
2 Total Likes
View groups...
Share
Share this post:

How to draw control-systems block diagrams?

In the documentation ClosedLoopResponsesWithAPIDController, There is a very nice block diagram. I want to create my own block diagrams similar to this. I clicked on the diagram and pressed "command-shift-E" to show the underlying expression. I found the expression below. While this is explicit and reasonably easy to modify and extend, For really big graphs (which I have) it will rapidly become too difficult to manage by hand. I wonder if there is an easier way to produce such graphics? Is there a tool I just don't know about for drawing and / or automatically laying out such things?

enter image description here

Graph[{1, 2, 3, 4, 5, 6, 7, 8, 
        9}, {{{1, 2}, {2, 3}, {3, 4}, {4, 5}, {5, 6}, {6, 7}, {6, 
    2}, {8, 4}, {9, 6}}, Null}, {
        EdgeLabels -> {DirectedEdge[8, 4] -> Placed[
                 Style["+", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], {1, {-0.8, 0.2}}], 
    DirectedEdge[3, 4] -> Placed[
                 Style["+", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], 0.9], 
    DirectedEdge[9, 6] -> Placed[
                 Style["+", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], {1, {-0.8, 0.2}}], 
    DirectedEdge[5, 6] -> Placed[
                 Style["+", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], 0.9], 
    DirectedEdge[6, 2] -> Placed[
                 Style["-", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], {0.965, {-0.7, 0}}], 
    DirectedEdge[1, 2] -> Placed[
                 Style["+", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], 0.9]}, 
         EdgeShapeFunction -> {}, 
         EdgeStyle -> {
             GrayLevel[0, 1]}, Epilog -> {
             Text[
               Style["u", {FontFamily -> "Helvetica", 
                   GrayLevel[0, 1], 12}], {2.5, 0.1}]}, 
  ImageSize -> 500, 
         VertexCoordinates -> {{0., 0.}, {0.7, 0.}, {1.8, 0.}, {2.9, 
     0.}, {3.9, 0.}, {5., 0.}, {5.6, 0.}, {
             2.9, 0.66}, {5., 0.66}}, VertexLabels -> {1 -> Placed[
                 Style["r", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], Center], 6 -> Placed[
                 Style["", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], Center], 9 -> Placed[
                 Style["m", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], Center], 2 -> Placed[
                 Style["", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], Center], 8 -> Placed[
                 Style["d", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], Center], 7 -> Placed[
                 Style["y", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], Center], 3 -> Placed[
                 Style["PID controller", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], Center], 4 -> Placed[
                 Style["", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], Center], 5 -> Placed[
                 Style["linear system", {FontFamily -> "Helvetica", 
                     GrayLevel[0, 1], 12}], Center]}, 
         VertexShapeFunction -> {
            3 -> "Square", 4 -> "Circle", 7 -> "Square", 
    5 -> "Square", 9 -> "Square", 1 -> "Square", 6 ->
              "Circle", 8 -> "Square", 2 -> "Circle"}, 
         VertexSize -> {8 -> {0.1, 0.1}, 3 -> {0.6, 0.2}, 
    2 -> {0.125, 0.125}, 1 -> {0.1, 0.1}, 9 -> {0.1, 0.1}, 
             4 -> {0.125, 0.125}, 6 -> {0.125, 0.125}, 
    5 -> {0.6, 0.2}, 7 -> {0.1, 0.1}}, 
         VertexStyle ->
   {2 -> Directive[GrayLevel[1], 
      EdgeForm[{GrayLevel[0], AbsoluteThickness[1]}]], 
    1 -> Directive[Opacity[0], EdgeForm[{}]],
    8 -> Directive[Opacity[0], EdgeForm[{}]],
    7 -> Directive[Opacity[0], EdgeForm[{}]],
    5 -> Directive[GrayLevel[1], 
      EdgeForm[{GrayLevel[0], AbsoluteThickness[1]}]],
    6 -> Directive[GrayLevel[1], 
      EdgeForm[{GrayLevel[0], AbsoluteThickness[1]}]],
    4 -> Directive[GrayLevel[1], 
      EdgeForm[{GrayLevel[0], AbsoluteThickness[1]}]],
    9 -> Directive[Opacity[0], EdgeForm[{}]],
    3 -> Directive[GrayLevel[1], 
      EdgeForm[{GrayLevel[0], AbsoluteThickness[1]}]]
    }}]
POSTED BY: Brian Beckman
Posted 10 years ago

One way to get technical diagrams into Mathematica is to construct them in SystemModeler and then use the function WSMModelData to get the diagram.

Here I've constructed a simple control system in SystemModeler:SystemModeler Diagram, using Modelica.Blocks

Next, I fetch the diagram into Mathematica:

WSMModelData["controlSystem", "Diagram"]

enter image description here

I know that the icons in this library (Modelica.Blocks) doesn't looks like the typical textbook example you mentioned. If you are going to draw and use a large number of diagrams like this, it might be worthwhile to create custom components in SystemModeler that looks exactly like you want them to. (It's easy, there are drawing tools and everything you need)

POSTED BY: Johan Rhodin
Reply to this discussion
Community posts can be styled and formatted using the Markdown syntax.
Reply Preview
Attachments
Remove
or Discard

Group Abstract Group Abstract