DEMO_febio_0071_pneunet_actuator_set_01

Below is a demonstration for:

Contents

Keywords

clear; close all; clc;

Plot settings

fontSize=20;
faceAlpha1=0.8;
markerSize=40;
markerSize2=20;
lineWidth=3;

Control parameters

% Path names
defaultFolder = fileparts(fileparts(mfilename('fullpath')));
savePath=fullfile(defaultFolder,'data','temp');

% Defining file names
febioFebFileNamePart='tempModel';
febioFebFileName=fullfile(savePath,[febioFebFileNamePart,'.feb']); %FEB file name
febioLogFileName=fullfile(savePath,[febioFebFileNamePart,'.txt']); %FEBio log file name
febioLogFileName_disp=[febioFebFileNamePart,'_disp_out.txt']; %Log file name for exporting displacement
febioLogFileName_stress=[febioFebFileNamePart,'_stress_out.txt']; %Log file name for exporting force

%Load
appliedPressure1=0.05;
appliedPressure2=appliedPressure1/10;

%Define applied force
appliedForce=[1e-12 0 0];

%Material parameter set
c1=1; %Shear-modulus-like parameter
m1=2; %Material parameter setting degree of non-linearity
k_factor=50; %Bulk modulus factor
k=c1*k_factor; %Bulk modulus

c2=50*c1; %Shear-modulus-like parameter
m2=2; %Material parameter setting degree of non-linearity
k2=c2*k_factor; %Bulk modulus

% FEA control settings
numTimeSteps=10; %Number of time steps desired
opt_iter=25; %Optimum number of iterations
max_refs=opt_iter*2; %Max reforms
max_ups=0; %Set to zero to use full-Newton iterations
max_retries=5; %Maximum number of retires
dtmin=(1/numTimeSteps)/100; %Minimum time step size
dtmax=(1/numTimeSteps); %Maximum time step size

runMode='external';%'internal';
actuatorLengthDesired=100;

pointSpacing=2;
periodSize=10;
numPeriods=ceil(actuatorLengthDesired/periodSize);

heightFactor=1.4; %To scale height wrt period size
widthFactor=1; %To scale width wrt period size

numElementsPeriod=ceil(periodSize./pointSpacing);
if numElementsPeriod<4
    numElementsPeriod=4;
end

numElementsLength=((numPeriods-1)*numElementsPeriod)+(numElementsPeriod-1);
modelLength=numElementsLength.*pointSpacing;
modelHeight_X=periodSize*heightFactor;
modelWidth_Y=periodSize*widthFactor;

numElementsHeight_X=ceil(modelHeight_X./pointSpacing);
if numElementsHeight_X<6
    numElementsHeight_X=6;
end

numElementsWidth_Y=ceil(modelWidth_Y./pointSpacing);
if numElementsWidth_Y<1
    numElementsWidth_Y=1;
end

boxDim=[modelHeight_X modelWidth_Y modelLength];
boxEl=[numElementsHeight_X numElementsWidth_Y numElementsLength];

[meshStruct]=hexMeshBox(boxDim,boxEl);

E_bar=meshStruct.E;
V_bar=meshStruct.V;
F_bar=meshStruct.F;
Fb_bar=meshStruct.Fb;
Cb_bar=meshStruct.faceBoundaryMarker;

VE_bar=patchCentre(E_bar,V_bar);

CZ=VE_bar(:,3);
CZ=CZ-min(CZ);
CZ=CZ./max(CZ);
CZ=round((CZ.*(numElementsLength-1)))+1;

CW=VE_bar(:,1);
CW=CW-min(CW);
CW=CW./max(CW);
CW=round((CW.*(numElementsHeight_X-1)))+1;

CD=rem(CZ,numElementsPeriod);

logicKeep1=~(CD==0 & CW>3);

E1=E_bar(logicKeep1,:);
F1=element2patch(E1);
[indBoundary1]=tesBoundary(F1);

logicKeep2=any(ismember(E1,F1(indBoundary1,:)),2);
F2=element2patch(E1(logicKeep2,:));
[indBoundary2]=tesBoundary(F2);

Fb=F2(indBoundary2,:);
Cb=7*ones(size(Fb,1),1);

for q=1:1:6
    F_Cb1=Fb_bar(Cb_bar==q,:);
    logicNow=all(ismember(Fb,F_Cb1),2);
    Cb(logicNow)=q;
end
Cb(~any(ismember(Fb,F1(indBoundary1,:)),2))=0;

Removed unused nodes and clean up index matrices

[E,V,indFix2]=patchCleanUnused(E1(logicKeep2,:),V_bar);
V(:,1)=V(:,1)-min(V(:,1));
Fb=indFix2(Fb);
F=indFix2(F2);

V2=V;
V2(:,1)=-V2(:,1);
V=[V;V2];

Fb=[Fb;fliplr(Fb)+size(V2,1)];
F=[F;fliplr(F)+size(V2,1)];
cShift=max(Cb(:))+1;
Cb=[Cb;Cb+cShift];

indicesInnerSurface=unique(Fb(Cb==1,:));
logicElementsInner=any(ismember(E,indicesInnerSurface),2);

E1=E;
E2=E(:,[5 6 7 8 1 2 3 4]);
E2=E2(~logicElementsInner,:);

E=[E1;E2+size(V2,1)];
C=[ones(size(E1,1),1); 2*ones(size(E2,1),1);];
[F,V,~,ind2]=mergeVertices(F,V);
Fb=ind2(Fb);
E=ind2(E);
indicesInnerSurface=ind2(indicesInnerSurface);

actuatorLength=max(V(:,3))-min(V(:,3));

Defining the boundary conditions

The visualization of the model boundary shows colors for each side of the disc. These labels can be used to define boundary conditions.

%Define supported node sets
bcSupportList=unique(Fb(ismember(Cb,[5 5+cShift]),:)); %Node set part of selected face

bcPrescribeList=unique(Fb(ismember(Cb,[6 6+cShift]),:)); %Node set part of selected face

%Get pressure faces
F_pressure1=Fb(Cb==0,:);
F_pressure2=Fb(Cb==cShift,:);
ind2=unique(E(C==2,:));
d=max(V(ind2,1));
V(ind2,1)=V(ind2,1)-d;
V(:,1)=V(:,1)+d/2;

% [E,V,indFix]=patchCleanUnused(E,V);
% bcSupportList=indFix(bcSupportList);
% bcPrescribeList=indFix(bcPrescribeList);
% F_pressure1=indFix(F_pressure1);
% F_pressure2=indFix(F_pressure2);

[F,CF]=element2patch(E,C,'hex8');

[F,V,~,indFix]=mergeVertices(F,V);
E=indFix(E);
bcSupportList=indFix(bcSupportList);
bcPrescribeList=indFix(bcPrescribeList);
F_pressure1=indFix(F_pressure1);
F_pressure2=indFix(F_pressure2);

indb=tesBoundary(F);
Fb=F(indb,:);
cFigure; hold on;
gpatch(F,V,CF,'k',0.5);
% plotV(V(indicesInnerSurface,:),'k.','MarkerSize',markerSize);
axisGeom;
colormap(turbo(250)); icolorbar;
camlight headlight;
gdrawnow;

Visualizing boundary conditions. Markers plotted on the semi-transparent model denote the nodes in the various boundary condition lists.

hf=cFigure;
title('Boundary conditions','FontSize',fontSize);
xlabel('X','FontSize',fontSize); ylabel('Y','FontSize',fontSize); zlabel('Z','FontSize',fontSize);
hold on;

gpatch(Fb,V,'w','none',0.5);

hl(1)=plotV(V(bcSupportList,:),'k.','MarkerSize',markerSize);
hl(2)=gpatch(F_pressure1,V,'r','k',1);
hl(3)=gpatch(F_pressure2,V,'b','k',1);
hl(4)=plotV(V(bcPrescribeList,:),'g.','MarkerSize',markerSize);

patchNormPlot(F_pressure1,V);
legend(hl,{'BC full support','Pressure surface 1','Pressure surface 2','BC force'});

axisGeom(gca,fontSize);
camlight headlight;
gdrawnow;

Split element regions (central plate and sides);

XE=patchCentre(E,V(:,1));

logicElementsInner=abs(XE)<eps;

E1=E(~logicElementsInner,:); %Other elements
E2=E(logicElementsInner,:); %Inner element layer
E=[E1;E2];

[F1]=element2patch(E1);
[F2]=element2patch(E2);
cFigure; hold on;
gpatch(F1,V,'bw','k',0.5);
gpatch(F2,V,'rw','k',0.5);
axisGeom;
colormap(turbo(250)); icolorbar;
camlight headlight;
gdrawnow;

Defining the FEBio input structure

See also febioStructTemplate and febioStruct2xml and the FEBio user manual.

%Get a template with default settings
[febio_spec]=febioStructTemplate;

%febio_spec version
febio_spec.ATTR.version='4.0';

%Module section
febio_spec.Module.ATTR.type='solid';

%Control section
febio_spec.Control.analysis='STATIC';
febio_spec.Control.time_steps=numTimeSteps;
febio_spec.Control.step_size=1/numTimeSteps;
febio_spec.Control.solver.max_refs=max_refs;
febio_spec.Control.solver.qn_method.max_ups=max_ups;
febio_spec.Control.time_stepper.dtmin=dtmin;
febio_spec.Control.time_stepper.dtmax=dtmax;
febio_spec.Control.time_stepper.max_retries=max_retries;
febio_spec.Control.time_stepper.opt_iter=opt_iter;

%Material section
materialName1='Material1';
febio_spec.Material.material{1}.ATTR.name=materialName1;
febio_spec.Material.material{1}.ATTR.type='Ogden';
febio_spec.Material.material{1}.ATTR.id=1;
febio_spec.Material.material{1}.c1=c1;
febio_spec.Material.material{1}.m1=m1;
febio_spec.Material.material{1}.c2=c1;
febio_spec.Material.material{1}.m2=-m1;
febio_spec.Material.material{1}.k=k;

materialName2='Material2';
febio_spec.Material.material{2}.ATTR.name=materialName2;
febio_spec.Material.material{2}.ATTR.type='Ogden';
febio_spec.Material.material{2}.ATTR.id=2;
febio_spec.Material.material{2}.c1=c2;
febio_spec.Material.material{2}.m1=m2;
febio_spec.Material.material{2}.c2=c2;
febio_spec.Material.material{2}.m2=-m2;
febio_spec.Material.material{2}.k=k2;

%Mesh section
% -> Nodes
febio_spec.Mesh.Nodes{1}.ATTR.name='nodeSet_all'; %The node set name
febio_spec.Mesh.Nodes{1}.node.ATTR.id=(1:size(V,1))'; %The node id's
febio_spec.Mesh.Nodes{1}.node.VAL=V; %The nodel coordinates

% -> Elements
partName1='Part1';
febio_spec.Mesh.Elements{1}.ATTR.name=partName1; %Name of this part
febio_spec.Mesh.Elements{1}.ATTR.type='hex8'; %Element type
febio_spec.Mesh.Elements{1}.elem.ATTR.id=(1:1:size(E1,1))'; %Element id's
febio_spec.Mesh.Elements{1}.elem.VAL=E1; %The element matrix

partName2='Part2';
febio_spec.Mesh.Elements{2}.ATTR.name=partName2; %Name of this part
febio_spec.Mesh.Elements{2}.ATTR.type='hex8'; %Element type
febio_spec.Mesh.Elements{2}.elem.ATTR.id=size(E1,1)+(1:1:size(E2,1))'; %Element id's
febio_spec.Mesh.Elements{2}.elem.VAL=E2; %The element matrix

% -> Surfaces
surfaceName1='LoadedSurface1';
febio_spec.Mesh.Surface{1}.ATTR.name=surfaceName1;
febio_spec.Mesh.Surface{1}.quad4.ATTR.id=(1:1:size(F_pressure1,1))';
febio_spec.Mesh.Surface{1}.quad4.VAL=F_pressure1;

surfaceName2='LoadedSurface2';
febio_spec.Mesh.Surface{2}.ATTR.name=surfaceName2;
febio_spec.Mesh.Surface{2}.quad4.ATTR.id=(1:1:size(F_pressure2,1))';
febio_spec.Mesh.Surface{2}.quad4.VAL=F_pressure2;

% -> NodeSets
nodeSetName1='bcSupportList';
febio_spec.Mesh.NodeSet{1}.ATTR.name=nodeSetName1;
febio_spec.Mesh.NodeSet{1}.VAL=mrow(bcSupportList);

%MeshDomains section
febio_spec.MeshDomains.SolidDomain{1}.ATTR.name=partName1;
febio_spec.MeshDomains.SolidDomain{1}.ATTR.mat=materialName1;
febio_spec.MeshDomains.SolidDomain{2}.ATTR.name=partName2;
febio_spec.MeshDomains.SolidDomain{2}.ATTR.mat=materialName2;

%Boundary condition section
% -> Fix boundary conditions
febio_spec.Boundary.bc{1}.ATTR.name='zero_displacement_xyz';
febio_spec.Boundary.bc{1}.ATTR.type='zero displacement';
febio_spec.Boundary.bc{1}.ATTR.node_set=nodeSetName1;
febio_spec.Boundary.bc{1}.x_dof=1;
febio_spec.Boundary.bc{1}.y_dof=1;
febio_spec.Boundary.bc{1}.z_dof=1;

%Loads section
% -> Surface load
febio_spec.Loads.surface_load{1}.ATTR.type='pressure';
febio_spec.Loads.surface_load{1}.ATTR.surface=surfaceName1;
febio_spec.Loads.surface_load{1}.pressure.ATTR.lc=1;
febio_spec.Loads.surface_load{1}.pressure.VAL=appliedPressure1;
febio_spec.Loads.surface_load{1}.symmetric_stiffness=1;

febio_spec.Loads.surface_load{2}.ATTR.type='pressure';
febio_spec.Loads.surface_load{2}.ATTR.surface=surfaceName2;
febio_spec.Loads.surface_load{2}.pressure.ATTR.lc=1;
febio_spec.Loads.surface_load{2}.pressure.VAL=appliedPressure2;
febio_spec.Loads.surface_load{2}.symmetric_stiffness=1;

%LoadData section
% -> load_controller
febio_spec.LoadData.load_controller{1}.ATTR.id=1;
febio_spec.LoadData.load_controller{1}.ATTR.type='loadcurve';
febio_spec.LoadData.load_controller{1}.interpolate='LINEAR';
febio_spec.LoadData.load_controller{1}.points.point.VAL=[0 0; 1 1];

%Output section
% -> log file
febio_spec.Output.logfile.ATTR.file=febioLogFileName;
febio_spec.Output.logfile.node_data{1}.ATTR.file=febioLogFileName_disp;
febio_spec.Output.logfile.node_data{1}.ATTR.data='ux;uy;uz';
febio_spec.Output.logfile.node_data{1}.ATTR.delim=',';
febio_spec.Output.logfile.node_data{1}.VAL=1:size(V,1);

febio_spec.Output.logfile.element_data{1}.ATTR.file=febioLogFileName_stress;
febio_spec.Output.logfile.element_data{1}.ATTR.data='s1';
febio_spec.Output.logfile.element_data{1}.ATTR.delim=',';
febio_spec.Output.logfile.element_data{1}.VAL=1:size(E,1);

% Plotfile section
febio_spec.Output.plotfile.compression=0;

Quick viewing of the FEBio input file structure

The febView function can be used to view the xml structure in a MATLAB figure window.

febView(febio_spec); %Viewing the febio file

Exporting the FEBio input file

Exporting the febio_spec structure to an FEBio input file is done using the febioStruct2xml function.

febioStruct2xml(febio_spec,febioFebFileName); %Exporting to file and domNode
% febView(febioFebFileName);

Running the FEBio analysis

To run the analysis defined by the created FEBio input file the runMonitorFEBio function is used. The input for this function is a structure defining job settings e.g. the FEBio input file name. The optional output runFlag informs the user if the analysis was run succesfully.

febioAnalysis.run_filename=febioFebFileName; %The input file name
febioAnalysis.run_logname=febioLogFileName; %The name for the log file
febioAnalysis.disp_on=1; %Display information on the command window
febioAnalysis.runMode=runMode;

[runFlag]=runMonitorFEBio(febioAnalysis);%START FEBio NOW!!!!!!!!
 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-------->    RUNNING/MONITORING FEBIO JOB    <-------- 01-May-2023 09:17:50
FEBio path: /home/kevin/FEBioStudio/bin/febio4
# Attempt removal of existing log files                01-May-2023 09:17:50
 * Removal succesful                                   01-May-2023 09:17:50
# Attempt removal of existing .xplt files              01-May-2023 09:17:51
 * Removal succesful                                   01-May-2023 09:17:51
# Starting FEBio...                                    01-May-2023 09:17:51
  Max. total analysis time is: Inf s
 * Waiting for log file creation                       01-May-2023 09:17:51
   Max. wait time: 30 s
 * Log file found.                                     01-May-2023 09:17:51
# Parsing log file...                                  01-May-2023 09:17:51
    number of iterations   : 12                        01-May-2023 09:17:52
    number of reformations : 12                        01-May-2023 09:17:52
------- converged at time : 0.1                        01-May-2023 09:17:52
    number of iterations   : 12                        01-May-2023 09:17:53
    number of reformations : 12                        01-May-2023 09:17:53
------- converged at time : 0.2                        01-May-2023 09:17:53
    number of iterations   : 12                        01-May-2023 09:17:53
    number of reformations : 12                        01-May-2023 09:17:53
------- converged at time : 0.3                        01-May-2023 09:17:53
    number of iterations   : 12                        01-May-2023 09:17:54
    number of reformations : 12                        01-May-2023 09:17:54
------- converged at time : 0.4                        01-May-2023 09:17:54
    number of iterations   : 12                        01-May-2023 09:17:55
    number of reformations : 12                        01-May-2023 09:17:55
------- converged at time : 0.5                        01-May-2023 09:17:55
    number of iterations   : 12                        01-May-2023 09:17:56
    number of reformations : 12                        01-May-2023 09:17:56
------- converged at time : 0.6                        01-May-2023 09:17:56
    number of iterations   : 12                        01-May-2023 09:17:56
    number of reformations : 12                        01-May-2023 09:17:56
------- converged at time : 0.7                        01-May-2023 09:17:56
    number of iterations   : 12                        01-May-2023 09:17:57
    number of reformations : 12                        01-May-2023 09:17:57
------- converged at time : 0.8                        01-May-2023 09:17:57
    number of iterations   : 12                        01-May-2023 09:17:58
    number of reformations : 12                        01-May-2023 09:17:58
------- converged at time : 0.9                        01-May-2023 09:17:58
    number of iterations   : 10                        01-May-2023 09:17:58
    number of reformations : 10                        01-May-2023 09:17:58
------- converged at time : 1                          01-May-2023 09:17:58
 Elapsed time : 0:00:07                                01-May-2023 09:17:58
 N O R M A L   T E R M I N A T I O N
# Done                                                 01-May-2023 09:17:58
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Import FEBio results

if runFlag==1 %i.e. a succesful run

Importing nodal displacements from a log file

    dataStruct=importFEBio_logfile(fullfile(savePath,febioLogFileName_disp),0,1);

    %Access data
    N_disp_mat=dataStruct.data; %Displacement
    timeVec=dataStruct.time; %Time

    %Create deformed coordinate set
    V_DEF=N_disp_mat+repmat(V,[1 1 size(N_disp_mat,3)]);

Plotting the simulated results using anim8 to visualize and animate deformations

    DN_magnitude=sqrt(sum(N_disp_mat(:,:,end).^2,2)); %Current displacement magnitude

    % Create basic view and store graphics handle to initiate animation
    hf=cFigure; %Open figure
    gtitle([febioFebFileNamePart,': Press play to animate']);
    title('Displacement magnitude [mm]','Interpreter','Latex')
    hp=gpatch(Fb,V_DEF(:,:,end),DN_magnitude,'k',1); %Add graphics object to animate
%     hp.Marker='.';
%     hp.MarkerSize=markerSize2;
    hp.FaceColor='interp';

    axisGeom(gca,fontSize);
    colormap(gjet(250)); colorbar;
    caxis([0 max(DN_magnitude)]);
    axis(axisLim(V_DEF)); %Set axis limits statically
    camlight headlight;

    % Set up animation features
    animStruct.Time=timeVec; %The time vector
    for qt=1:1:size(N_disp_mat,3) %Loop over time increments
        DN_magnitude=sqrt(sum(N_disp_mat(:,:,qt).^2,2)); %Current displacement magnitude

        %Set entries in animation structure
        animStruct.Handles{qt}=[hp hp]; %Handles of objects to animate
        animStruct.Props{qt}={'Vertices','CData'}; %Properties of objects to animate
        animStruct.Set{qt}={V_DEF(:,:,qt),DN_magnitude}; %Property values for to set in order to animate
    end
    anim8(hf,animStruct); %Initiate animation feature
    drawnow;

Importing element stress from a log file

    dataStruct=importFEBio_logfile(fullfile(savePath,febioLogFileName_stress),0,1);

    %Access data
    E_stress_mat=dataStruct.data;

    E_stress_mat(isnan(E_stress_mat))=0;

Plotting the simulated results using anim8 to visualize and animate deformations

    [CV]=faceToVertexMeasure(E,V,E_stress_mat(:,:,end));

    % Create basic view and store graphics handle to initiate animation
    hf=cFigure; %Open figure
    gtitle([febioFebFileNamePart,': Press play to animate']);
    title('$\sigma_{1}$ [MPa]','Interpreter','Latex')
    hp=gpatch(Fb,V_DEF(:,:,end),CV,'k',1); %Add graphics object to animate
%     hp.Marker='.';
%     hp.MarkerSize=markerSize2;
    hp.FaceColor='interp';

    axisGeom(gca,fontSize);
    colormap(gjet(250)); colorbar;
    caxis([min(E_stress_mat(:)) max(E_stress_mat(:))]);
    axis(axisLim(V_DEF)); %Set axis limits statically
    camlight headlight;

    % Set up animation features
    animStruct.Time=timeVec; %The time vector
    for qt=1:1:size(N_disp_mat,3) %Loop over time increments

        [CV]=faceToVertexMeasure(E,V,E_stress_mat(:,:,qt));

        %Set entries in animation structure
        animStruct.Handles{qt}=[hp hp]; %Handles of objects to animate
        animStruct.Props{qt}={'Vertices','CData'}; %Properties of objects to animate
        animStruct.Set{qt}={V_DEF(:,:,qt),CV}; %Property values for to set in order to animate
    end
    anim8(hf,animStruct); %Initiate animation feature
    drawnow;
end

GIBBON www.gibboncode.org

Kevin Mattheus Moerman, [email protected]

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License: https://github.com/gibbonCode/GIBBON/blob/master/LICENSE

GIBBON: The Geometry and Image-based Bioengineering add-On. A toolbox for image segmentation, image-based modeling, meshing, and finite element analysis.

Copyright (C) 2006-2022 Kevin Mattheus Moerman and the GIBBON contributors

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.