Efficient dynamic constraints for animating articulated figures

Kokkevis, E.; Metaxas, D.; Badler, N. I.

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Efficient dynamic constraints for animating articulated figures

Kokkevis, E.·Metaxas, D.·Badler, N. I.

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Abstract

This paper presents an efficient dynamics-based computer animation system for simulating and controlling the motion of articulated figures. A non-trivial extension of Featherstone's O(n) recursive forward dynamics algorithm is derived which allows enforcing one or more constraints on the animated figures. We demonstrate how the constraint force evaluation algorithm we have developed makes it possible to simulate collisions between articulated figures, to compute the results of impulsive forces, to enforce joint limits, to model closed kinematic loops, and to robustly control motion at interactive rates. Particular care has been taken to make the algorithm not only fast, but also easy to implement and use. To better illustrate how the constraint force evaluation algorithm works, we provide pseudocode for its major components. Additionally, we analyze its computational complexity and finally we present examples demonstrating how our system has been used to generate interactive, physically correct complex motion with small user effort.

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NASA Discipline Space Human Factors Non-NASA Center Computer Simulation Acceleration Models, Anatomic Locomotion/physiology Computer Graphics Algorithms Biomechanics Joints Imaging, Three-Dimensional Human

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Kokkevis, E., Metaxas, D., Badler, N. I.. 1998-06-01. Efficient dynamic constraints for animating articulated figures. https://ntrs.nasa.gov/citations/20040088163

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