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--- parallel_flexure_guide_transfer [2020/06/04 12:23]
marijn.nijenhuis
+++ parallel_flexure_guide_transfer [2021/05/05 14:17] (current)
marijn.nijenhuis
@@ Line 21: / Line 21: @@
 For details, see the [[full_syntax|SPACAR Light full syntax]].
-The resulting transfer function is plotted in the figure below. The first eigenfrequency is approximately 10 rad/s;  the first parasitic eigenfrequency appears at 360 rad/s.
+The resulting transfer function between the input and the first output is plotted in the figure below. The first eigenfrequency is approximately 10 rad/s;  the first parasitic eigenfrequency appears at 360 rad/s.
-{{::transfer pfg.png?direct|}}
+{{::bode.png?direct|}}
+Note that in case of multiple inputs and/or outputs, the resulting state-space structure in MATLAB will also indicate with named labels what these inputs and outputs are (i.e. node number and displacement, velocity or force).
 An example file for providing the input for SPACAR Light and plotting the transfer function is provided below.
@@ Line 67: / Line 69: @@
 eprops(1).elems    = [1 3];            %Add this set of properties to elements 1 and 3
 eprops(1).emod     = 210e9;            %E-modulus [Pa]
-eprops(1).smod     = 70e9;             %G-modulus [Pa]
+eprops(1).smod     = 70e9;             %Shear modulus [Pa]
 eprops(1).dens     = 7800;             %Density [kg/m^3]
 eprops(1).cshape   = 'rect';           %Rectangular cross-section
@@ Line 76: / Line 78: @@
 eprops(1).color    = 'grey';           %Color of elements
 eprops(1).opacity  = 0.7;              %Opacity of elements
-eprops(1).cw       = true;             %Enable (approximate) torsional stiffening due to constraint warping
+% eprops(1).warping  = true;             %Enable modeling of warping, e.g. for the effect of constrained warping
 %Property set 2
@@ Line 90: / Line 92: @@
 %% OPTIONAL ARGUMENTS
 opt.transfer = {true 0.01};       %Calculation of state-space equations (with relative damping 0.01)
-opt.filename = 'file';
+opt.filename = 'file';            %Names of files that are produced
 %% CALL SPACAR_LIGHT
@@ Line 96: / Line 98: @@
 %% Plot transfer function
-figure
+%set some convenient defaults for the plot. Not necessary, but they can improve the plots
-bode(out.statespace,{1,10000})
+bodeopt = bodeoptions;
-grid minor
+bodeopt.Title.String = 'Title for this plot';
+bodeopt.FreqUnits = 'Hz'; %default frequency units
+bodeopt.Xlim = [1,4000]; %frequency axis limits
+bodeopt.Grid = 'on'; %show a grid
+bodeopt.Title.FontSize = 14; %font size for title
+bodeopt.XLabel.FontSize = 12; %font size for xlabels
+bodeopt.YLabel.FontSize = 12; %font size for ylabels
+bodeopt.TickLabel.FontSize = 12; %font size for the ticks (numbers on axes)
+bodeopt.InputLabels.FontSize = 12;
+bodeopt.OutputLabels.FontSize = 12;
+bodeopt.PhaseMatching = 'on'; %phase matching: adding multiples of 360 so that:
+bodeopt.PhaseMatchingFreq = 1; %--at this frequency
+bodeopt.PhaseMatchingValue = 0; %--the phase is close to this value
+h = bodeplot(out.statespace,bodeopt); %make the plot
 </code>

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