Autonomous Robots

, Volume 41, Issue 3, pp 743–758 | Cite as

AssistOn-Ankle: a reconfigurable ankle exoskeleton with series-elastic actuation

  • Ahmetcan Erdogan
  • Besir Celebi
  • Aykut Cihan Satici
  • Volkan Patoglu


We present the kinematics, optimal dimensional synthesis, series-elastic actuation, control, characterization and user evaluation of AssistOn-Ankle, a reconfigurable, powered exoskeleton for ankle rehabilitation. AssistOn-Ankle features reconfigurable kinematics for delivery of both range of motion (RoM)/strengthening and balance/proprioception exercises. In particular, through lockable joints, the underlying kinematics can be configured to either a self-aligning parallel mechanism that can naturally cover the whole RoM of the human ankle, or another parallel mechanism that can support the ground reaction forces/torques transferred to the ankle. Utilizing a single device to treat multiple phases of treatment is advantageous for robotic rehabilitation, since not only does it decrease the device cost and help with the space requirements, but also shorten the time it takes for patients to familiarize with the device. Bowden cable-based series-elastic actuation of AssistOn-Ankle allows for a remote placement of the motors/drivers to result in a compact design with low apparent inertia, while also enabling high-fidelity force/impedance control and active backdriveability of the device.


Rehabilitation robotics Ankle exoskeleton Reconfigurable mechanisms Series elastic actuation 


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Ahmetcan Erdogan
    • 1
  • Besir Celebi
    • 1
  • Aykut Cihan Satici
    • 1
  • Volkan Patoglu
    • 1
  1. 1.Faculty of Engineering and Natural SciencesSabancı UniversityIstanbulTurkey

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