Improving energy efficiency in robot limbs through hydraulic dangle

Julian S. Whitman; Mike Meller; Ephrahim Garcia

doi:10.1117/12.2175588

26 March 2015 Improving energy efficiency in robot limbs through hydraulic dangle

Julian S. Whitman, Mike Meller, Ephrahim Garcia

Proceedings Volume 9429, Bioinspiration, Biomimetics, and Bioreplication 2015; 94291M (2015) https://doi.org/10.1117/12.2175588
Event: SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring, 2015, San Diego, California, United States

Abstract

Animals often allow their limbs to swing passively under their own inertia. For example, about 40% of a human walking gait consists of the primarily passive swing phase. Current hydraulic robots employ traditional actuation methods in which fluid power is expended for all limb movements, even when passive dynamics could be utilized. “Dangle” is the ability to allow a hydraulic actuator to freely sway in response to external loads, in which both sides of the actuator are disconnected from pressure and connected to the tank. Dangle offers the opportunity for efficiency gains by enabling the use of momentum, gravity, and external loads to move a limb without expending fluid power. To demonstrate these efficiency gains, this paper presents an experiment that compares the fluid power consumed to actuate a two degree of freedom hydraulic leg following a human walking gait cycle trajectory in both a traditional manner and utilizing dangle. It was shown that the use of dangle can decrease fluid power consumption by 20% by utilizing pendular dynamics during the swing phase. At speeds higher than the free dangling rate, more power must be used to maintain the desired trajectory due to damping inherent in the configuration. The use of dangle as a power saving method when driving hydraulic limbs could increase operation time for untethered hydraulic walking robots.

Citation Download Citation

Julian S. Whitman, Mike Meller, and Ephrahim Garcia "Improving energy efficiency in robot limbs through hydraulic dangle", Proc. SPIE 9429, Bioinspiration, Biomimetics, and Bioreplication 2015, 94291M (26 March 2015); https://doi.org/10.1117/12.2175588

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available