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bioRxiv · 10.1101/2021.07.06.451400

Harmonic Passive Motion Paradigm

Tiseo, C.·Charitos, S. R.·Mistry, M.
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Abstract

How humans robustly interact with external dynamics is not yet fully understood. This work presents a hierarchical architecture of semi-autonomous controllers that can control the redundant kinematics of the limbs during dynamic interaction, even with delays comparable to the nervous system. The postural optimisation is performed via a non-linear mapping of the system kineto-static properties, and it allows independent control of the end-effector trajectories and the arms stiffness. The proposed architecture is tested in a physical simulator in the absence of gravity, presence of gravity, and with gravity plus a viscous force field. The data indicate that the architecture can generalise motor strategies to different environmental conditions. The experiments also verify the existence of a deterministic solution to the task-separation principle. The architecture is also compatible with Optimal Feedback Control and the Passive Motion Paradigm. The existence of a deterministic mapping implies that this task could be encoded in neural networks capable of generalisation of motion strategies to affine tasks.

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Tiseo, C., Charitos, S. R., Mistry, M.. 2021-07-08. Harmonic Passive Motion Paradigm. https://doi.org/10.1101/2021.07.06.451400

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