Developments of a Knee Motion Assist Mechanism for Wearable Robot with a Non-circular Gear and Grooved Cams

  • H. TeradaEmail author
  • Y. Zhu
  • M. Suzuki
  • C. Cheng
  • R. Takahashi
Conference paper
Part of the Mechanisms and Machine Science book series (Mechan. Machine Science, volume 3)


For wearable robot, the active knee joint assist mechanism has been developed. Especially, this mechanism is driven by a non-circular gear and grooved cams. This mechanism rotates and slides simultaneously, which has 2 degree-of-freedom. And relation between a rotation and a sliding motion can approximate arbitrary mathematical function. And using this mechanism, the knee joint can flex until 130degrees. It is larger than the angle of a conventional joint. In this report, the motion of a knee flexion is analyzed. We propose the fundamental design method. And to move smoothly, we investigate the motion curves. And the optimized locus of a non-circular gear pitch and a grooved cam are shown. Also, the prototype knee joint assist mechanism is evaluated. It is clear that proposed mechanism is useful for the motion assist of a knee joint.


Wearable robot Knee joint Motion assist Non-circular gear Grooved cam 



The author is grateful to Dr. Katori, Tecpha-Japan Co., for cooperating to make the non-circular gear.


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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • H. Terada
    • 1
    Email author
  • Y. Zhu
    • 1
  • M. Suzuki
    • 1
  • C. Cheng
    • 1
  • R. Takahashi
    • 2
  1. 1.University of YamanashiYamanashiJapan
  2. 2.Suncall Engineering CorporationJapan

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