Browse > Article
http://dx.doi.org/10.15701/kcgs.2017.23.3.105

On-line Trajectory Optimization Based on Automatic Time Warping  

Han, Daseong (Handong Global University)
Noh, Junyong (KAIST)
Shin, Joseph S. (Handong Global University)
Abstract
This paper presents a novel on-line trajectory optimization framework based on automatic time warping, which performs the time warping of a reference motion while optimizing character motion control. Unlike existing physics-based character animation methods where sampling times for a reference motion are uniform or fixed during optimization in general, our method considers the change of sampling times on top of the dynamics of character motion in the same optimization, which allows the character to effectively respond to external pushes with optimal time warping. In order to do so, we formulate an optimal control problem which takes into account both the full-body dynamics and the change of sampling time for a reference motion, and present a model predictive control framework that produces an optimal control policy for character motion and sampling time by repeatedly solving the problem for a fixed-span time window while shifting it along the time axis. Our experimental results show the robustness of our framework to external perturbations and the effectiveness on rhythmic motion synthesis in accordance with a given piece of background music.
Keywords
Physics-based; Character Animation; Motion Control; Time Warping;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Raibert, Marc H., and Jessica K. Hodgins. "Animation of dynamic legged locomotion." ACM SIGGRAPH Computer Graphics. Vol. 25. No. 4. ACM, 1991.
2 Hodgins, Jessica K., et al. "Animating human athletics." Proceedings of the 22nd annual conference on Computer graphics and interactive techniques. ACM, 1995.
3 Kim, Tae-hoon, Sang Il Park, and Sung Yong Shin. "Rhythmicmotion synthesis based on motion-beat analysis." ACM Transactions on Graphics (TOG). Vol. 22. No. 3. ACM, 2003.
4 Wu, Jia-chi, and Zoran Popovic. "Terrain-adaptive bipedal locomotion control." ACM Transactions on Graphics (TOG) 29.4(2010): 72.
5 Tassa Y., Erez T., Todorov E.: Synthesis and stabilization of complex behaviors through online trajectory optimization. In Intelligent Robots and Systems (IROS), 2012 IEEE/RSJ International Conference on (2012), IEEE, pp. 4906-4913.
6 Han, Daseong, Haegwang Eom, and Junyong Noh. "Data‐guided Model Predictive Control Based on Smoothed Contact Dynamics." Computer Graphics Forum. Vol. 35. No. 2. 2016.
7 Yin, KangKang, Kevin Loken, and Michiel van de Panne. "Simbicon: Simple biped locomotion control." ACM Transactions on Graphics (TOG). Vol. 26. No. 3. ACM, 2007.
8 Pratt, Jerry, Chee-Meng Chew, Ann Torres, Peter Dilworth, and Gill Pratt. "Virtual model control: An intuitive approach for bipedal locomotion." The International Journal of Robotics Research 20, no. 2 (2001): 129-143.   DOI
9 Coros, Stelian, Philippe Beaudoin, and Michiel van de Panne. "Generalized biped walking control." ACM Transactions on Graphics (TOG). Vol. 29. No. 4. ACM, 2010.
10 Coros, Stelian, Andrej Karpathy, Ben Jones, Lionel Reveret, and Michiel Van De Panne. "Locomotion skills for simulated quadrupeds." In ACM Transactions on Graphics (TOG), vol. 30, no. 4, p. 59. ACM, 2011.
11 Peng, Xue Bin, Glen Berseth, and Michiel van de Panne. "Dynamic terrain traversal skills using reinforcement learning." ACM Transactions on Graphics (TOG) 34.4 (2015): 80.
12 Muico, Uldarico, Yongjoon Lee, Jovan Popovic, and Zoran Popovic. "Contact-aware nonlinear control of dynamic characters." In ACM Transactions on Graphics (TOG), vol. 28, no. 3, p. 81. ACM, 2009..
13 Witkin, Andrew, and Zoran Popovic. "Motion warping." Proceedings of the 22nd annual conference on Computer graphics and interactive techniques. ACM, 1995.
14 da Silva, Marco, Yeuhi Abe, and Jovan Popovic. "Interactive simulation of stylized human locomotion." ACM Transactions on Graphics (TOG) 27.3 (2008): 82.   DOI
15 Muico, Uldarico, Jovan Popovic, and Zoran Popovic. "Composite control of physically simulated characters." ACM Transactions on Graphics (TOG) 30.3 (2011): 16.
16 Ye, Yuting, and C. Karen Liu. "Optimal feedback control for character animation using an abstract model." ACM Transactions on Graphics (TOG). Vol. 29. No. 4. ACM, 2010.
17 da Silva M., Abe Y., Popovic J.: Simulation of human motion data using short-horizon model-predictive control. In Computer Graphics Forum (2008), vol. 27, Wiley Online Library, pp. 371-380.   DOI
18 Kwon, Taesoo, and Jessica Hodgins. "Control systems for human running using an inverted pendulum model and a reference motion capture sequence." Proceedings of the 2010 ACM SIGGRAPH/Eurographics Symposium on Computer Animation. Eurographics Association, 2010.
19 Han, Daseong, et al. "On-line real-time physics-based predictive motion control with balance recovery." Computer Graphics Forum. Vol. 33. No. 2. 2014.
20 Todorov E.: Convex and analytically-invertible dynamics with contacts and constraints: Theory and implementation in mujoco. In IEEE Conference on Robotics and Automation (ICRA) (2014).
21 Hsu, Eugene, Marco da Silva, and Jovan Popovic. "Guided time warping for motion editing." Proceedings of the 2007 ACM SIGGRAPH/Eurographics symposium on Computer animation. Eurographics Association, 2007.
22 Rose, Charles, Michael F. Cohen, and Bobby Bodenheimer. "Verbs and adverbs: Multidimensional motion interpolation." IEEE Computer Graphics and Applications 18.5 (1998): 32-40.   DOI
23 Park, Sang Il, et al. "On-line motion blending for real‐time locomotion generation." Computer Animation and Virtual Worlds 15.3-4 (2004): 125-138.   DOI
24 Liu, C. Karen, Aaron Hertzmann, and Zoran Popovic. "Composition of complex optimal multi-character motions." Proceedings of the 2006 ACM SIGGRAPH/Eurographics symposium on Computer animation. Eurographics Association, 2006.
25 Stewart, David E., and Jeffrey C. Trinkle. "An implicit timestepping scheme for rigid body dynamics with inelastic collisions and coulomb friction." International Journal for Numerical Methods in Engineering 39.15 (1996): 2673-2691.   DOI
26 Mordatch, Igor, Martin De Lasa, and Aaron Hertzmann. "Robust physics-based locomotion using low-dimensional planning." ACM Transactions on Graphics (TOG). Vol. 29. No. 4. ACM, 2010.
27 Jacobson D., Mayne D.: Differential dynamic programming.
28 Featherstone, Roy. "Rigid body dynamics algorithms (Vol. 49)." Springer Berlin 3.6 (2008): 7.
29 Tassa, Yuval, Nicolas Mansard, and Emo Todorov. "Controllimited differential dynamic programming." Robotics and Automation (ICRA), 2014 IEEE International Conference on. IEEE, 2014.
30 Guenter, Brian. "Efficient symbolic differentiation for graphics applications." ACM Transactions on Graphics (TOG) 26.3 (2007): 108.   DOI