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Real time falling animation with active and protective responses

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Abstract

Combined with motion capture and dynamic simulation, characters in animation have realistic motion details and can respond to unexpected contact forces. This paper proposes a novel and real-time character motion generation approach which introduces a parallel process, and uses an approximate nearest neighbor optimization search method. Besides, we employ a support vector machine (SVM), which is trained on a set of samples and predicts a subset of our ‘return-to’ motion capture (mocap) database in order to reduce the search time. In the dynamic simulation process, we focus on designing a biomechanics based controller which detects the balance of the characters in locomotion and drives them to take several active and protective responses when they fall to the ground in order to reduce the injuries to their bodies. Finally, we show the time costs in synthesis and the visual results of our approach. The experimental results indicate that our motion generation approach is suitable for interactive games or other real-time applications.

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References

  1. Mandel, M.: Versatile and interactive virtual humans: Hybrid use of data-driven and dynamics-based motion synthesis. PhD thesis, Carnegie Mellon University (2004)

  2. Arikan, O., Forsyth, D.A., O’Brien, J.F.: Pushing people around. In: Proceedings of the 2005 ACM Siggraph/Eurographics Symposium on Computer Animation, SCA ’05, Los Angeles, California, July 29–31, 2005, pp. 59–66. ACM, New York (2005)

    Chapter  Google Scholar 

  3. Tang, B.: Study on generating reactive motions for human animation. PhD thesis, Zhejiang University (2006)

  4. Hsiao, E.T., Robinovitch, S.N.: Biomechanical influences on balance recovery by stepping. J. Biomech. 32(9), 1099–1106 (1999)

    Article  Google Scholar 

  5. Sabick, M.B., Hay, J.G., Banks, S.A.: Active response decrease impact forces at the hip and shoulder in falls to the side. J. Biomech. 32(9), 993–998 (1999)

    Article  Google Scholar 

  6. Fabio, F., Stephen, N.R.: Reducing hip fracture risk during sideways falls: Evidence in young adults of the protective effects of impact to the hands and stepping. J. Biomech. 40(9), 2612–2618 (2007)

    Google Scholar 

  7. Hof, A.L., Gazendam, M.G.J., Sinke, W.E.: The condition for dynamic stability. J. Biomech. 38(9), 1–8 (2005)

    Google Scholar 

  8. Pai, Y.C., Patton, J.: Center of mass velocity-position predictions for balance control. J. Biomech. 30(4), 347–354 (2007)

    Article  Google Scholar 

  9. Kover, L., Gleicher, M., Pighin, F.: Motion graphs. ACM Trans. Graph. 21(3), 473–482 (2002)

    Google Scholar 

  10. Reitsma, P.S.A., Pollard, N.S.: Evaluating motion graphs for character navigation. In: Proceedings of the 2004 ACM Siggraph/Eurographics Symposium on Computer Animation (Grenoble, France, August 27–29), pp. 89–98 (2004)

  11. Heck, R., Gleicher, M.: Parametric motion graphs. In: Proceedings of the 2007 Symposium on Interactive 3D Graphics and Games I3D’07 (Seattle, Washington, April 30–May 2), pp. 129–136. ACM, New York (2007)

    Chapter  Google Scholar 

  12. Faloutsos, P., Panne, M.V.D., Terzopoulos, D.: Composable controllers for physics-based character animation. In: Proceedings of the 28th Annual Conference on Computer Graphics and Interactive Techniques SIGGRAPH ’01, pp. 251–260. ACM, New York (2001)

    Chapter  Google Scholar 

  13. Fang, A.C., Pollard, N.S.: Efficient synthesis of physically valid human motion. ACM Trans. Graph. 22(3), 417–426 (2003)

    Article  Google Scholar 

  14. Yin, K.K., Loken, K., Panne, M.: SIMBICON: Simple biped locomotion control. ACM Trans. Graph. (SIGGRAPH 2007) 26(3), Article 105, 10 pages (2007). DOI:10.1145/1239451.1239556

  15. Shin, H.J., Kovar, L., Gleicher, M.: Physical touch-up of human motions. In: The 11th Pacific Conference on Computer Graphics and Applications, pp. 194–203 (2003)

  16. Shapiro, A., Pighin, F.: Hybrid control for interactive character animation. In: The 11th Pacific Conference on Computer Graphics and Applications, pp. 455–461 (2003)

  17. Komura, T., Ho, E.S.L., Lau, R.W.H.: Animating reactive motion using momentum-based inverse kinematics. Comput. Animat. Virtual Worlds 16(3), 213–223 (2005)

    Article  Google Scholar 

  18. Zordan, V.B., Majkowska, A., Chiu, B., Fast, M.: Dynamic response for motion capture animation, ACM Trans. Graph. 24(3), 697–701 (2005)

    Google Scholar 

  19. Wu, M., Ji, L.H., Jin, D.W., Wang, R.C., Zhang, J.C.: Recovery strategy from perturbations of the upper body during standing using mechanical energy analysis. J. Tsinghua Univ. (Sci&Tech) 43(2), 152–155 (2003) (in Chinese)

    Google Scholar 

  20. Kry, P.G., Pai, D.K.: Interaction capture and synthesis. ACM Trans. Graph. 25(3), 872–880 (2006)

    Article  Google Scholar 

  21. Wu, M., Ji, L.H., Jin, D.W., Pai, Y.C.: Minimal step length necessary for recovery of forward balance loss with a single step. J. Biomech. 40(9), 1559–1566 (2007)

    Article  Google Scholar 

  22. Yin, K., Coros, S., Beaudoin, P., Panne, M.: Continuation methods for adapting simulated skills. ACM Trans. Graph. 27(3), 1–7 (2008)

    Article  Google Scholar 

  23. Mount, D., Arya, S.: Approximate nearest neighbour queries in fixed dimensions. In: Proceedings of the Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp. 271–280 (1993)

  24. Zordan, V.B., Macchietto, A., Medina, J., Soriano, M., Wu, C.C.: Interactive dynamic response for games. In: Proceedings of the 2007 ACM SIGGRAPH Symposium on Video Games Sandbox’07, (San Diego, California, August 4–5), pp. 9–14. ACM, New York (2007)

    Google Scholar 

  25. Treuille, A., Lee, Y., Popovi’c, Z.: Near-optimal character animation with continuous control. ACM Trans. Graph. (SIGGRAPH 2007) 26(3), Article 7, 7 pages (2007). DOI:10.1145/1239451.1239458

  26. Miall, R.C., Weir, D.J., Wolpert, D.M., Stein, J.F.: Is the cerebellum a Smith predictor? J. Motor Behav. 25(3), 203–216 (1993)

    Google Scholar 

  27. Komura, T., Leung, H., Kuffner, J.: Animating reactive motions for biped locomotion. In: Proceedings of ACM Symposium on Virtual Reality Software and Technology, pp. 32–40 (2004)

  28. Stephen, N.R., Rebecca, B., Jessica, M.: Effect of the “squat protective response” on impact velocity during backward falls. J. Biomech. 37(9), 1329–1337 (2004)

    Article  Google Scholar 

  29. Whitney, D.E.: Resolved motion rate control of manipulators and human prostheses, IEEE Trans. Man-Mach. Syst. 10(2), 47–53 (1969)

    Article  MathSciNet  Google Scholar 

  30. Delp, S.L., Loan, J.P., Hoy, M.G., Zajac, F.E., Topp, E.L., Rosen, J.M.: An interactive graphics-based model of the lower extremity to study orthopedic surgical procedures, IEEE Trans. Biomed. Eng. 37(8), 757–767 (1990)

    Article  Google Scholar 

  31. Tang, B., Pan, Z.G., Zheng, L., Zhang, M.M.: Interactive generation of falling motions. Comput. Animat. Virtual Worlds 17(3–4), 271–279 (2006)

    Article  Google Scholar 

  32. Lee, J., Shin, S.Y.: A hierarchical approach to interactive motion editing for humanlike figures. In: Proceedings of the 26th Annual Conference on Computer Graphics and Interactive Techniques, pp. 39–48. ACM, New York (1999)

    Chapter  Google Scholar 

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Correspondence to Wenzhi Chen.

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Pan, Z., Cheng, X., Chen, W. et al. Real time falling animation with active and protective responses. Vis Comput 25, 487–497 (2009). https://doi.org/10.1007/s00371-009-0321-9

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  • DOI: https://doi.org/10.1007/s00371-009-0321-9

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