Real time surgical simulation using a lattice- continuum approach

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SOFA

Real time surgical simulation using a

lattice-continuum approach

Implementation and validation

Huu Phuoc Bui

1

_{, Hadrien Courtecuisse}

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_{, Stéphane P.A. Bordas}

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_{, Stéphane Cotin}

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1

_{ICube laboratory, University of Strasbourg}

2

_{University of Luxembourg}

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SOFA

HP Bui, University of Strasbourg

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Some words about me

► PhD at University of Grenoble (November 2013)

Multiscale approach of concrete structure failure

► Postdoc at 3SR laboratory (2014)

Segmentation of cracks in concrete structure

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SOFA

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Context

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SOFA

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Context

► Computer-based simulation

► Surgical training

► Guidance

► Surgical robotics

_{Simulation of lens extraction}

Simulation of brain tumor resection

Courtecuisse et al, 2013

► Challenges: cutting, tearing,

needle insertion, ...

► Topological changes

► Contacts

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SOFA

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Objectives

► Development of numerical tool

► Real-time simulation

► Multi-domain

: continuum-lattice approach

► Multiscale

: macro, mesoscopic scale (material scale)

► The algorithm is implemented

into SOFA framework

▲ Computational gains

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SOFA

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Lattice approach

Discretization by 1D elements

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Discrete model: suitable for discontinuity problems

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Simplicity to incorporate fracture, cutting

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Modeling of material heterogeneity

○ Beam element

○ Truss element

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SOFA

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SOFA

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Continuum-lattice approach

Constraint-based solution

Courtecuisse et al, 2013_{Duriez et al, 2006}

FEM LEM

With Lagrange multiplier λ such that

Interface

Step 1: Free motions x₁free_,_x 2

free _{A x = b with λ = 0}

Step 2: Corrective motions x₁cor_,_x 2 cor A x = hHλ with b = 0 λ_i FEM LEM

Step 3: Apply correction _{x = x}free_{+ x}cor

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Validation tests:

3D tensile test

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Validation tests:

3D bending test

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SOFA

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Bending test:

FEM approach

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SOFA

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SOFA

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Fracture application

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SOFA

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Conclusions & Perspectives

☺Continuum-lattice coupling is valid

☺Fracture simulation

Conclusions

Perspectives

☻Dynamic topological changes

☻Cutting of soft tissue

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SOFA

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Conclusion & Perspectives

►A paper on SOFA implementation with validation tests

►A paper on fracture results ►A paper on real-time cutting

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SOFA

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