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Title: Tuning a robot servomotor to exhibit muscle-like dynamics
This work shows one way to tune a servomotor controller to make it perform in a similar way to a biomechanical model of an insect leg joint. Three key metrics were considered: the equilibrium angle of the joint as a function of antagonistic inputs; the dynamics of the free response when perturbed; and the dynamics of active motions. We model an insect leg joint as a hinge actuated by a pair of antagonistic linear Hill muscles that drive a rigid distal leg segment. Passive forces from the exoskeleton are also modeled as passive viscoelastic elements (PVE). We approximate parameter values for the model based on the biomechanics literature, and then dynamically scale them to the scale of our robot, Drosophibot. We show how to tune the servo’s control mapping and feedback gain to mimic the dynamically scaled model of the animal joint.  more » « less
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8th International Conference, Living Machines 2019
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Medium: X
Sponsoring Org:
National Science Foundation
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