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Simulating 2D Gaits with a Phase-Indexed Tracking Controller
July/August 2011 (vol. 31 no. 4)
pp. 22-33
Yeuhi Abe, Massachusetts Institute of Technology
Jovan Popovi´c, Adobe Systems
Tracking controllers produce realistic motion in simulations by mimicking an input motion. However, current time-indexed trackers adhere strictly to the input motion's timing, causing a lack of robustness. A new phase-indexed tracker for 2D characters can deviate from the input motion's timing. Compared to time-indexed tracking with a state-of-the-art nonlinear quadratic regulator, phase-indexed tracking can withstand force perturbations up to an order of magnitude larger. The phase-indexed controller employs motion constraints that induce a reduced dynamic for which we can design control policies that incorporate prediction.

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Index Terms:
motion constraints, tracking, character controller, animation, physical simulation, computer graphics, graphics and multimedia
Citation:
Yeuhi Abe, Jovan Popovi´c, "Simulating 2D Gaits with a Phase-Indexed Tracking Controller," IEEE Computer Graphics and Applications, vol. 31, no. 4, pp. 22-33, July-Aug. 2011, doi:10.1109/MCG.2011.62
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