A selective recruitment strategy for exploiting muscle-like actuator impedance properties

Two leading qualities of skeletal muscle that produce
good performance in uncertain environments are damage
tolerance and the ability to modulate impedance. For this
reason, robotics researchers are greatly interested in discovering
the key characteristics of muscles that give them these properties
and replicating them in actuators for robotic devices. This
paper describes a method to harness the redundancy present in
muscle-like actuation systems composed of multiple motor units
and shows that they have these same two qualities. By carefully
choosing which motor units are recruited, the impedance viewed
from the environment can be modulated while maintaining
the same overall activation level. The degree to which the
impedance can be controlled varies with total activation level
and actuator length.
Discretizing the actuation effort into multiple parts that work
together, inspired by the way muscle fibers work in the human
body, produces damage-tolerant behavior. This paper shows
that this not only produces reasonably good resolutions without
inordinate numbers of units, but gives the control system the
ability to set the impedance along with the drive effort to the
load.

Jaar van publicatie:2015

Toegankelijkheid:Open