1. Motion Modeling for Online Locomotion Synthesis Taesoo Kwon and Sung Yong Shin KAIST

2. Outline Motivation Related work Overview Motion analysis Motion synthesis Conclusions Future Work

3. Motivation Real-time locomotion synthesis Motion rearrangement : realism Motion blending : efficiency and controllability Hybrid approach –Locomotive motion generation [PSS02, PSS04] –Rhythmic motion synthesis [KPS03] Premise: motion labeling

4. Related Work Motion Segmentation [Bindiganavale & Badler, 1998;Fod et al., 2002; Kim et al., 2003] Motion Classification [Arikan et al., 2003;Kovar & Gleicher, 2004;Forbes & Fiume 2005;Mueller & Roeder 2005] Motion Labeling for blending [Kim et al., 2003]

5. Overview motion specifications desired motion example motions motion analysis hierarchical motion transition graph motion synthesis

6. Motion Analysis Issues –Motion segmentation –Motion classification –Graph construction Biomechanical observations –[Per92,Win90]

7. Biomechanical Observations Center of mass trajectory right foot left foot walkrun transition

8. Motion segmentation Criteria for motion segmentation –Simple enough for intuitive parameterization –Long enough to contain motion semantics –An important motion feature should not be split  Split at every COM peak

9. Motion Classification String encoding – Pros –avoid troublesome time-warping –more robust than numerical computation

10. Motion Classification Footstep patterns (a) S (b) R (c) L (d) D (e) F

11. Motion Classification String Encoding (ideal case)

12. Motion Classification String Encoding (ideal case) R D L

13. Motion Classification String Encoding (ideal case) F R F

14. Motion Classification String Encoding (ideal case) R D L F

15. Motion Classification String Encoding (ideal case)

16. Refinement False peak –Concatenate two motion segments Missing peak –Divide a motion segment into two

17. Graph Construction

19. Motion Analysis Results O(n) –2Ghz PC (AMD 64, 2GB memory) –For 7.4 min locomotion, about 10 seconds Movie

20. Motion Synthesis LDRRDLLDRF … …

21. Motion Synthesis Motion specification Motion parameter

22. Motion Sythesis How to calculate –Two half cycles in cyclic motion – Regression analysis on

23. Motion Synthesis Motion blending : [PSS04][KG03][ACP02] Motion stitching : [GSKJ03] Motion retargeting : [SLSG01][KGS02]

24. Motion Synthesis Result 1000+ frames per second Movie –Path following –Online synthesis

25. Conclusion Motion labeling based on string encodings Hierarchical motion transition graph

26. Future work Footstep-driven motions such as dancing and boxing