How to plot frame structure with varying thickness?

I am using the Plot Frame Structure file from this link: https://www.mathworks.com/matlabcentral/fileexchange/74083-plot-frame-structure

and utilizing it to plot lattice structures. I am trying to plot the structures with varying element thickness such that the element thickness can be visualized (say if there are total of 8 elements in a frame. 5 of them are 1mm thick, 2 of them are 1.5mm thick and last one is 2mm thick. When plotting the frame, I want to create the structure with elements thickness proportional to these thickness value). Additionally, it will be good to have these thicker elements (1.5mm, 2mm in the example) represented with different color as well than baseline thickness size (1mm in example). I do have node coordinate matrix, element connectivity matrix and a column vector of each element thickness which correspondes to the element connectivity matrix.

Any help is higly appreciated.Thanks

Answer 1

[Saffan]

Hi Naresh,

You can modify the "plotStructure" function to plot the bars with varying thickness in the following way:

function plotStructure(nodes,bars,options)

% Plot nodes
if options.nodeOn == 1
    scatter3(nodes(:,1),nodes(:,2),nodes(:,3),10,'filled','MarkerEdgeColor','k','MarkerFaceColor','k')
end

% Plot bars
barX = [nodes(bars(:,1),1) nodes(bars(:,2),1)]';
barY = [nodes(bars(:,1),2) nodes(bars(:,2),2)]';
barZ = [nodes(bars(:,1),3) nodes(bars(:,2),3)]';
hold on
if ~isempty(options.barColor) && ~isempty(options.barWidth)
    for b=1:size(bars,1)
        line(barX(:,b),barY(:,b),barZ(:,b),'Color',options.barColor(b,:),'LineWidth',options.barWidth(b))
    end
else
    line(barX,barY,barZ,'Color','k')
end
hold off

% Other figure properties
gridMin = min(nodes);
gridMax = max(nodes);
xlim([gridMin(1) gridMax(1)])
ylim([gridMin(2) gridMax(2)])
zlim([gridMin(3) gridMax(3)])
pbaspect([1 1 gridMax(3)/gridMax(2)])
view(options.viewAngle(1),options.viewAngle(2))
axis off

end

To use the modified plotStructure function, you need to add an additional property “options.barWidth” to the options structure. This property will be passed as an input argument to plotStructure, similar to how the color of each bar is passed through “options.barColor”. The “options.barWidth” property must be a column vector with the thickness value for each bar, in the same order as the bars in the bars input matrix.

[Naresh Koju]

Thank you, Saffan, for the answer. I tried the updated function but did not see any visible thickness varation even when the thickness for differnet bars ranged from t =1 to t = 2.4.

I will really appreciate it if you help me in representing the thickness variation in more pronounced manner.

Thank you

[Saffan]

Hi Naresh,

Make sure that options.barWidth property is a vector of size numOfBars x 1.

Here is a sampe code snippet where I have modified example_diagrid.m file to call the modified function:

options.barColor = [repmat([0 0 1],vars.nDiags/2,1); ...
                    repmat([1 0 0],vars.nDiags/2,1); ...
                    repmat([1 1 0],vars.nBeams,1)]; 
exampleWidthVector = linspace(1,2.4,1080)';  
options.barWidth =exampleWidthVector;                                             
                                                  
plotStructure(nodes,bars,options)

I hope this helps.

[Naresh Koju]

Thank you Saffan for all your help. I had the options.barWidth property defined with a vector size of numOfBars x 1. I feel that the lineWidth variation is just not too large for me to be visibily distinguishable.

Thanks

Naresh