1. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
Deriving a Particle System from Continuum Mechanics for the Animation of Deformable Objects
Authors:
Olaf Etzmuss
Joachim Gross
Wolfgang Strasser
Presented By: Federico Bermudez
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

2. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
PROBLEM
Establish a link between discrete models and classical mathematical elasticity.
Derive a particle system model from a continuum model.
Assess the accuracy of the particle model.
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

3. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
MOTIVATION
Develop fast computational models of deformable objects.
Create computer animations of highly flexible materials such as cloth or textiles.
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

4. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
Linear Elasticity
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

5. Linear Elasticity - discretize
APPROACH
Linear Elasticity - discretize
Unit Tangent Vector
Unit Tangent Vector
Sampled Points
arc-length
curvature l
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH 5

6. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

7. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

8. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH 8

9. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH 9

10. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
Trousers and sweater -- 5,000 particles.
Generated by a quadrilateralization
Keeping the angles close to 90 degrees.
Dress has 3,200 particles. The computation of
10s simulation time --- takes approximately 190s
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

11. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

12. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
area
force
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

13. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
area
force
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

14. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
area
force
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

15. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
hanging textile
sheared textile
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

16. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
APPROACH
hanging textile with bend forces
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

17. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
Evaluation
Successfully show the link between discrete and continuum models.
Successfully demonstrated the deviation of a particle system from a continuum model.
Successfully presented how discretization affects the models accuracy.
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

18. Conclusion & Future Work
A particle system model can be derived from continuum mechanics by
Linearization
Local frame of reference
Successive finite difference discretization.
The model is sufficiently accurate for fast animation of highly deformable objects.
Future work will focus on matching triangular meshes with continuous models.
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH

19. MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH
Questions
Can this method be applied to model biological organs?
Is this technique useful only for animations of cloth or textiles?
28 Mar 2007
MSIM 842 VISUALIZATION II INSTRUCTOR: JESSICA R. CROUCH