Bio-inspired knee joint mechanism for a hydraulic quadruped robot

Hamza Khan, Roy Featherstone, Darwin G. Caldwell, Claudio Semini

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

21 Citations (Scopus)


Over the last few decades, legged robots are becoming a promising solution for rough terrain navigation, however, existing legged machines often lack versatility to perform a wide range of different gaits. To build a highly dynamic and versatile legged robot, it is essential to have lightweight legs with optimized design and suitable actuators for the desired robot performance and tasks. The design goals are to achieve 1) a wide range of motion for bigger foot workspace which will increase rough terrain walking performance by increasing the number of reachable footholds for each step, 2) optimized joint torque curve since torque output is related to joint angle if linear actuators like pistons are used. In this paper, we focus on the knee joint and propose the adaptation and optimization of the so-called isogram mechanism. It exhibits a changeable instantaneous center of rotation (CICR), similar to a human knee joint. We will show how an optimization of design parameters lead to a knee joint design that satisfies the above-mentioned goals. The main contributions of this paper are the kinematic and torque analysis of the isogram mechanism that is actuated by a linear actuator; the optimization of the mechanism's design parameters; a comparison between the proposed knee joint with the hinge-type knee joint of the quadruped robot HyQ; and experimental results of a proof-of-concept prototype leg featuring the proposed mechanism.

Original languageEnglish
Title of host publicationICARA 2015 - Proceedings of the 2015 6th International Conference on Automation, Robotics and Applications
EditorsDonald Bailey, Serge Demidenko, G. Sen Gupta
PublisherInstitute of Electrical and Electronics Engineers Inc.
Number of pages7
ISBN (Electronic)9781479964666
Publication statusPublished - 9 Apr 2015
Event6th International Conference on Automation, Robotics and Applications, ICARA 2015 - Queenstown, New Zealand
Duration: 17 Feb 201519 Feb 2015


Conference6th International Conference on Automation, Robotics and Applications, ICARA 2015
Country/TerritoryNew Zealand


  • Joints
  • Knee
  • Torque
  • Legged locomotion
  • Actuators
  • Optimization

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Artificial Intelligence
  • Computer Vision and Pattern Recognition
  • Computer Science Applications


Dive into the research topics of 'Bio-inspired knee joint mechanism for a hydraulic quadruped robot'. Together they form a unique fingerprint.

Cite this