Control and evaluation of a humanoid robot with rolling contact joints on its lower body

Frontiers in Robotics and AI

Robotics and AI

Nicholas Paine¹  Carlos Gonzalez²  Seung Hyeon Bang²  Luis Sentis³  Junhyeok Ahn⁴ 

[1] Apptronik, Inc., Austin, TX, United States;Department of Aerospace Engineering, University of Texas at Austin, Austin, TX, United States;Department of Aerospace Engineering, University of Texas at Austin, Austin, TX, United States;Apptronik, Inc., Austin, TX, United States;Department of Mechanical Engineering, University of Texas at Austin, Austin, TX, United States;

关键词: rolling contact joints;    whole-body control;    humanoid robots;    legged robots;    humanoid system integration;   

DOI  :  10.3389/frobt.2023.1164660

 received in 2023-02-13, accepted in 2023-09-26,  发布年份 2023

来源: Frontiers

【 摘 要 】

In this paper, we introduce a new teen-sized humanoid platform dubbed DRACO 3, custom-built by Apptronik and altered for practical use by the Human Centered Robotics Laboratory at The University of Texas at Austin. The form factor of DRACO 3 is such that it can operate safely in human environments while reaching objects at human heights. To approximate the range of motion of humans, this robot features proximal actuation and mechanical artifacts to provide a high range of hip, knee, and ankle motions. In particular, rolling contact mechanisms on the lower body are incorporated using a proximal actuation principle to provide an extensive vertical pose workspace. To enable DRACO 3 to perform dexterous tasks while dealing with these complex transmissions, we introduce a novel whole-body controller (WBC) incorporating internal constraints to model the rolling motion behavior. In addition, details of our WBC for DRACO 3 are presented with an emphasis on practical points for hardware implementation. We perform a design analysis of DRACO 3, as well as empirical evaluations under the lens of the Centroidal Inertia Isotropy (CII) design metric. Lastly, we experimentally validate our design and controller by testing center of mass (CoM) balancing, one-leg balancing, and stepping-in-place behaviors.

【 授权许可】

Unknown   
Copyright © 2023 Bang, Gonzalez, Ahn, Paine and Sentis.