Programmable compliance and equilibrium point control of a 2-DOF manipulator performing free-space, contact and transition tasks

Damien J. Clapa, Elizabeth A. Croft, Antony J. Hodgson

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


Programmable mechanical compliance (PMC) in actuation is desirable for human interaction tasks and important for producing biomimetic motion. In this paper, the equilibrium point (EP) hypothesis is proposed and implemented as a strategy for controlling programmable compliance. A two-DOF planar manipulator activated by McKibben actuators was constructed for the purpose of demonstrating the application of the equilibrium point hypothesis on a robotic platform. The equilibrium angle and stiffness of each of the joints on the manipulator can be independently programmed. The results presented herein show stable behavior for free motion, interaction and transition tasks using the EP hypothesis implemented with a linear PI control strategy.

Original languageEnglish
Title of host publicationProceedings of the ASME International Mechanical Engineering Congress and Exposition 2004
Number of pages8
Publication statusPublished - 1 Jan 2004
Externally publishedYes
EventASME International Mechanical Engineering Congress and Exposition 2004 - Anaheim, United States of America
Duration: 13 Nov 200419 Nov 2004


ConferenceASME International Mechanical Engineering Congress and Exposition 2004
Abbreviated titleIMECE 2004
Country/TerritoryUnited States of America


  • Air muscles
  • Equilibrium point control
  • Human-robot interaction
  • Mckibben actuators
  • Programmable mechanical compliance

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