From Motion Capture to Real-Time Character Animation

This paper describes a framework for animating virtual characters in real-time environments thanks to motion capture data. In this paper, we mainly focus on the adaptation of motion capture data to the virtual skeleton and to its environment. To speed-up this real-time process we introduce a morphology-independent representation of motion. Based on this representation, we have redesigned the methods for inverse kinematics and kinetics so that our method can adapt the motion thanks to spacetime constraints, including a control of the center of mass position. If the resulting motion doesn't satisfy general mechanical laws (such as maintaining the angular momentum constant during aerial phases) the current pose is corrected. External additional forces can also be considered in the dynamic correction module so that the character automatically bend his hips when pushing heavy objects, for example. All this process is performed in real-time.

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