Case Study IV: Geometrical Modeling of the Heart and
the HeadRob MacLeod, Moritz Dannhauer, Jonathan Bronson
Motivation
Mesh
Geometrical modeling for simulation
Pipeline Image Acq. &Processing
Segmentation & Structure Identification
Geometric Modeling& Fitting Structures
MeshingVolume Modeling
Simulation/Estimation
Verification/Validation
Discrete pointse.g., sensors
Boundary conditions
Measured Data
Visualization
Seg3
D
Cle
aver
SCIR
un
Shap
ewor
ks
Imag
eVis3
Dm
ap3D
SCIR
un
Meshing
CAD-basedMeshing
Meshing
Image Based Modeling
Challenges of MeshingIrregular features
Multiple materials
Mesh size
Adaptive mesh
Computationalcost
Internal surfaces
Examples in Biology
Non-manifold Interfaces
Conforming to Boundaries
A B
Non-Conforming Mesh
Conforming Mesh
Internal surface
Meshing packages
Example: Oxford Heart
Cross Section of Heart
BioMesh3D Tarantula
Comparison - Run Time
0
7.5
15
22.5
30
0.5
24
BioMesh3D Tarantula
Time [hours]
Comparison - Complexity
0
1.5
3
4.5
6
4.4
5.9
BioMesh3D Tarantula
Mesh nodes in [xMillion]
Comparison - Adaptivity
0
50000
100000
150000
200000
39171
175028
BioMesh3D Tarantula
Size variability of elements:std dev. of
volume [uM^3]
BioMesh3D Examples
BioMesh3D - Properties
Pros:
+ Conforming+ Highly Adaptive+ Preserve smooth/small features
- Lack of Robustness- Mediocre usability- Long run time- Poor control of node density - Inconsistent element quality
Cons:
New Meshing Approach:“Cleaver”
min(SICR)>=const
Bronson, J., Levine, J., and Whitaker, R. International Meshing Roundtable, 2012
Cleaver Example
Comparison - Torso
Conditionnumber
min(Dihedral Angle)
1E+011E+021E+031E+041E+051E+061E+071E+081E+091E+10
2.42E+07
2.94E+09
5.42E+06
0
2
4
6
8
0.40
7.4
Cleaver BioMesh3D CGAL
Example: Head Model
8 Materials Integrated electrodes
Comparison - Head Model
0
2.25
4.5
6.75
98.6
6.4
BioMesh3D Cleaver
Mesh nodes in [xMillion]
0
50
100
150
200
0.7
168
Time in [hours]
Cleaver in Action