Elementary Dynamic Actions: key structures for contact-rich manipulation

Johannes Lachner, Moses C. Nah, Federico Tessari, Neville Hogan

Keywords: Contact-rich manipulation, Motor primitives, Impedance Control, Peg-In-Hole

TL;DR: Review of motor primitives (submovements, oscillations, and impedance) and brief summary of our ongoing work on impedance learning.

Abstract:

Despite a slow neuromuscular system, humans
achieve impressive dexterity in physical interactions. It is
hypothesized that this is possible through "motor primitives,"
basic building blocks of motor control that enable dynamic
behavior with minimal high-level control. In this paper, we
review "Elementary Dynamic Actions" (EDA), which consist of
three classes of motor primitives: submovements, oscillations,
and impedance. We demonstrate how EDA can simplify robot
control for contact-rich manipulation by implementing a pegin-
hole task on a real robot. Our assembly strategy remained
unaffected by position errors of the insertion hole. Moreover,
different workpiece shapes could be assembled with the same set
of primitives. We briefly present our ongoing research to combine
EDA with learning, reducing the numbers programmerspecified
control parameters.

Submission Number: 12