Abstract
We present a method for precomputing robust task-based control policies for physically simulated characters. This allows for characters that can demonstrate skill and purpose in completing a given task, such as walking to a target location, while physically interacting with the environment in significant ways. As input, the method assumes an abstract action vocabulary consisting of balance-aware, step-based controllers. A novel constrained state exploration phase is first used to define a character dynamics model as well as a finite volume of character states over which the control policy will be defined. An optimized control policy is then computed using reinforcement learning. The final policy spans the cross-product of the character state and task state, and is more robust than the conrollers it is constructed from. We demonstrate real-time results for six locomotion-based tasks and on three highly-varied bipedal characters. We further provide a game-scenario demonstration.
Supplemental Material
Available for Download
The supplementary material contains two demos, runnable under Windows. To run the demos, launch the appropriate .bat file. We have included "no shaders" versions in order to maintain compatability on a wider range of machines. (1) Bird Mania birdmania.bat: with shaders birdmania_no_shaders.bat: no shaders (2) Bird Knockdown birdknockdown.bat: with shaders birdknockdown_no_shaders.bat: no shaders
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- Robust task-based control policies for physics-based characters
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