Conference Paper

Hierarchical motor learning and synthesis with passivity-based controller and phase oscillator

JST, ICORP, Kawaguchi
DOI: 10.1109/ROBOT.2008.4543620 Conference: Robotics and Automation, 2008. ICRA 2008. IEEE International Conference on
Source: IEEE Xplore

ABSTRACT In this paper, we propose a simple framework for learning and synthesis of fast and complex motor tasks. Where a passivity-based task-space controller acts not only as a full-body force control module, but also as an important module to generate phasic joint patterns. The generated joint patterns are encoded into the parameters of phase oscillators and form the synergy of the task. Then, similar and/or faster motions are synthesized by superposing the task space controller output and the oscillator output with the modified oscillator amplitudes and/or frequencies. We present some examples of whole-body motion synthesis on a human-sized biped humanoid robot including squatting, dancing and stepping while bipedal balancing. The simulation and experimental videos are supplemented.

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    ABSTRACT: We propose a new supervised learning and syn- thesis framework for fast and complex motor tasks. Wherein, a statics-based task-space controller acts not only as a full- body motion control module, but also as a module to generate synergetic joint patterns. The generated joint patterns are encoded into the parameters of phase trajectories of attractors and form the synergy of the task. Similar, but faster motions are synthesized by superposing the task-space controller output and the trajectory attractor output with the modified parameters, while learning dynamics and stiffness according to the task error. We demonstrate the proposed framework by simulating a balanced fast squat on a humanoid robot model.

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