Abstract
Finding torques that control a physical model to follow motion capture marker data can be complicated. We present a simple method for first constraining a physical model to follow marker data using forward simulation with intuitive parametrization. Essentially, the markers attach to the model through joint constraints and drag the body into position. We then use forward simulation to compute joint torques that produce the same movement. This is accomplished by adding constraints on the relative angular velocities of the body parts to the physical model. Framing the movement in terms of constraints on the model allows us to use the Open Dynamics physics engine (ODE) to find torques that simultaneously account for joint limits, body momentum, and ground/contact constraints. Although balanced movement still requires some external stabilizing torques, these torques are generally quite small and can potentially be addressed by minor changes in foot placement.
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References
Sugihara, T.: Solvability-unconcerned inverse kinematics by the levenberg-marquardt method. IEEE Transactions on Robotics 27(5), 984–991 (2011)
Zordan, V.B., Hodgins, J.K.: Motion capture-driven simulations that hit and react. In: Proceedings of the 2002 ACM SIGGRAPH/Eurographics Symposium on Computer Animation, SCA 2002, pp. 89–96. ACM, New York (2002)
Geijtenbeek, T., Pronost, N., Egges, A., Overmars, M.H.: Interactive character animation using simulated physics. In: Eurographics (State of the Art Reports) (2011)
Ko, H., Badler, N.: Animating human locomotion with inverse dynamics. IEEE Computer Graphics and Applications 16(2), 50–59 (1996)
Witkin, A., Kass, M.: Spacetime constraints. SIGGRAPH Comput. Graph. 22(4), 159–168 (1988)
van de Panne, M., Lamouret, A.: Guided optimization for balanced locomotion. In: Eurographics Workshop on Computer Animation and Simulation 1995, pp. 165–177 (1995)
Smith, R.: Intelligent Motion Control with an Artificial Cerebellum. PhD thesis, University of Auckland, New Zealand (July 1998)
Smith, R.: Constraints in rigid body dynamics. Best of Game Programming Gems (2008)
Isaacs, P.M., Cohen, M.F.: Controlling dynamic simulation with kinematic constraints. SIGGRAPH Comput. Graph. 21(4), 215–224 (1987)
Zordan, V.B., van der Horst, N.C.: Mapping optical motion capture data to skeletal motion using a physical model. In: Proceedings of the 2003 ACM SIGGRAPH/Eurographics Symposium on Computer Animation, SCA 2003, pp. 245–250. Eurographics Association, Aire-la-Ville (2003)
Faure, F., Debunne, G., Cani, M.P., Multon, F.: Dynamic analysis of human walking. In: Eurographics Workshop on Computer Animation and Simulation, EGCAS (September 1997), Published under the name Marie-Paule Cani-Gascuel
Zordan, V.B., Hodgins, J.K.: Tracking and modifying upper-body human motion data with dynamic simulation. In: Computer Animation and Simulation 1999, pp. 13–22. Eurographics (1999)
Shapiro, A., Pighin, F., Faloutsos, P.: Hybrid control for interactive character animation. In: Proceedings of the 11th Pacific Conference on Computer Graphics and Applications, PG 2003, p. 455. IEEE Computer Society, Washington, DC (2003)
Zordan, V.B., Majkowska, A., Chiu, B., Fast, M.: Dynamic response for motion capture animation. In: ACM SIGGRAPH 2005 Papers, SIGGRAPH 2005, pp. 697–701. ACM, New York (2005)
Wrotek, P., Jenkins, O.C., McGuire, M.: Dynamo: dynamic, data-driven character control with adjustable balance. In: Proceedings of the 2006 ACM SIGGRAPH Symposium on Videogames, Sandbox 2006, pp. 61–70. ACM, New York (2006)
Allen, B., Chu, D., Shapiro, A., Faloutsos, P.: On the beat!: timing and tension for dynamic characters. In: Proceedings of the 2007 ACM SIGGRAPH/Eurographics Symposium on Computer Animation, SCA 2007, pp. 239–247. Eurographics Association, Aire-la-Ville (2007)
Abe, Y., da Silva, M., Popović, J.: Multiobjective control with frictional contacts. In: Proceedings of the 2007 ACM SIGGRAPH/Eurographics Symposium on Computer Animation, SCA 2007, pp. 249–258. Eurographics Association, Aire-la-Ville (2007)
Liu, L., Yin, K., van de Panne, M., Shao, T., Xu, W.: Sampling-based contact-rich motion control. ACM Trans. Graph. 29, 128:1–128:10 (2010)
Ye, Y., Liu, C.K.: Optimal feedback control for character animation using an abstract model. ACM Trans. Graph. 29, 74:1–74:9 (2010)
Muico, U., Lee, Y., Popović, J., Popović, Z.: Contact-aware nonlinear control of dynamic characters. ACM Trans. Graph. 28(3), 81:1–81:9 (2009)
Liu, M., Micaelli, A., Evrard, P., Escande, A., Andriot, C.: Interactive dynamics and balance of a virtual character during manipulation tasks. In: 2011 IEEE International Conference on Robotics and Automation (ICRA), pp. 1676–1682 (May 2011)
Baraff, D.: Linear-time dynamics using lagrange multipliers. In: Proceedings of the 23rd Annual Conference on Computer Graphics and Interactive Techniques, SIGGRAPH 1996, pp. 137–146. ACM, New York (1996)
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Cooper, J.L., Ballard, D. (2012). Realtime, Physics-Based Marker Following. In: Kallmann, M., Bekris, K. (eds) Motion in Games. MIG 2012. Lecture Notes in Computer Science, vol 7660. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-34710-8_32
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DOI: https://doi.org/10.1007/978-3-642-34710-8_32
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