Understanding power loss due to mechanical antagonism and a new power-optimal pseudoinverse for redundant actuators

Nathan M. Cahill, Thomas Sugar, Matthew Holgate, Kyle Schroeder

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Comparatively slow growth in power storage and generation makes power-efficient designs desirable for legged robot systems. One important cause of power losses in robotic systems is the mechanical antagonism phenomenon, i.e. one or more motors being used as brakes while the others exert positive energy. This two-part paper first develops a rigorous understanding of mechanical antagonism in multiactuator robotic limbs. We show that, for a 6-DoF robot arm, there exist 4096 distinct regions in the force-velocity space of the end effector (the regions are distinguishable by the sign of the actuator powers). Only sixty-four of these regions correspond with operating points where all actuators exert positive power into the system. In the second part of the paper, we formulate a convex optimization problem which minimizes mechanical antagonism in redundant manipulators. We solve the optimization problem which becomes the derivation for a new, power-optimal, pseudoinverse for non-square Jacobians. In fact, two such pseudoinverses are derived: one for statically determinate systems, such as serial manipulators, and one for statically indeterminate systems, such as parallel manipulators.

Original languageEnglish (US)
Title of host publication41st Mechanisms and Robotics Conference
PublisherAmerican Society of Mechanical Engineers (ASME)
Volume5B-2017
ISBN (Electronic)9780791858189
DOIs
StatePublished - Jan 1 2017
Externally publishedYes
EventASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE 2017 - Cleveland, United States
Duration: Aug 6 2017Aug 9 2017

Other

OtherASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE 2017
CountryUnited States
CityCleveland
Period8/6/178/9/17

Fingerprint

Antagonism
Pseudo-inverse
Manipulators
Actuator
Robotics
Actuators
Robots
Redundant manipulators
Convex optimization
End effectors
Brakes
Redundant Manipulator
Optimization Problem
Legged Robots
Parallel Manipulator
Manipulator
Convex Optimization
Robot
Distinct
Minimise

ASJC Scopus subject areas

  • Mechanical Engineering
  • Computer Graphics and Computer-Aided Design
  • Computer Science Applications
  • Modeling and Simulation

Cite this

Cahill, N. M., Sugar, T., Holgate, M., & Schroeder, K. (2017). Understanding power loss due to mechanical antagonism and a new power-optimal pseudoinverse for redundant actuators. In 41st Mechanisms and Robotics Conference (Vol. 5B-2017). American Society of Mechanical Engineers (ASME). https://doi.org/10.1115/DETC2017-67942

Understanding power loss due to mechanical antagonism and a new power-optimal pseudoinverse for redundant actuators. / Cahill, Nathan M.; Sugar, Thomas; Holgate, Matthew; Schroeder, Kyle.

41st Mechanisms and Robotics Conference. Vol. 5B-2017 American Society of Mechanical Engineers (ASME), 2017.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Cahill, NM, Sugar, T, Holgate, M & Schroeder, K 2017, Understanding power loss due to mechanical antagonism and a new power-optimal pseudoinverse for redundant actuators. in 41st Mechanisms and Robotics Conference. vol. 5B-2017, American Society of Mechanical Engineers (ASME), ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE 2017, Cleveland, United States, 8/6/17. https://doi.org/10.1115/DETC2017-67942
Cahill NM, Sugar T, Holgate M, Schroeder K. Understanding power loss due to mechanical antagonism and a new power-optimal pseudoinverse for redundant actuators. In 41st Mechanisms and Robotics Conference. Vol. 5B-2017. American Society of Mechanical Engineers (ASME). 2017 https://doi.org/10.1115/DETC2017-67942
Cahill, Nathan M. ; Sugar, Thomas ; Holgate, Matthew ; Schroeder, Kyle. / Understanding power loss due to mechanical antagonism and a new power-optimal pseudoinverse for redundant actuators. 41st Mechanisms and Robotics Conference. Vol. 5B-2017 American Society of Mechanical Engineers (ASME), 2017.
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