Journal of Medical and Biological Engineering

, Volume 38, Issue 4, pp 556–572 | Cite as

Vi-RABT: A Platform-Based Robot for Ankle and Balance Assessment and Training

  • Amir Bahador FarjadianEmail author
  • Mohsen Nabian
  • Amber Hartman
  • Sheng-Che Yen
Original Article


Ankle sprain is a significant public health concern that can compromise ambulation and activities of daily living. An effective rehabilitation protocol includes objective range of motion (ROM), strength, and proprioception assessment and training. The virtually interfaced robotic ankle and balance trainer (vi-RABT) is a platform-based robot to streamline the ankle and balance rehabilitation. vi-RABT is a 2-degree of freedom robot about dorsiflexion/plantarflexion and inversion/eversion of ankle joint. It has a compact electromechanical design instrumented with actuators, angle and torque sensors and equipped with an impedance controller. vi-RABT hosts interactive games, which are designed by therapists, to turn the repetitive therapy into a more engaging experience. The system was used in a preliminary study for ankle joint assessment and training of two healthy human subjects. The assessment results were compared with outcomes using standard equipment in which the ankle joint ROM and strength were found close to the benchmark measures. In training blocks, the impedance controller corrected the individuals’ motion in the goal-oriented interactive game, improving the movement speed and accuracy while delivering satisfactory torque and angle tracking performance. The preliminary results shows that vi-RABT can streamline ankle joint assessment and training in the seated posture. The relatively smaller size of vi-RABT may increase the range and frequency of applications in private clinics and hospitals.


Rehabilitation robotics Ankle sprain Assessment and training Assistive/Resistive Training 



The source of inspiration for pursuing our research in this direction stems from our former advisor, Prof. Constantinos Mavroidis. We deeply regret he is not among us to see the outcome of our research effort, which has led to the publication of this paper. We dedicate this paper to him and no words could express how much we respect and missed him along this way. We would like to thank the undergraduate mechanical engineering students: Ally Bugliari, Paul Douçot, Nate Lavins, Alex Mazzotta, Jan P. Valenzuela, and Sean Suri for contribution to the mechanical design, fabrication and assembly. We also thank Dr. Maureen Holden for contribution at the time of this research.


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Copyright information

© Taiwanese Society of Biomedical Engineering 2017

Authors and Affiliations

  • Amir Bahador Farjadian
    • 1
    Email author
  • Mohsen Nabian
    • 2
  • Amber Hartman
    • 3
  • Sheng-Che Yen
    • 4
  1. 1.Bioengineering, Biomedical Mechatronics Laboratory, Department of Mechanical & Industrial EngineeringNortheastern UniversityBostonUSA
  2. 2.Department of Mechanical and Industrial EngineeringNortheastern UniversityBostonUSA
  3. 3.GastoniaUSA
  4. 4.Department of Physical Therapy, Movement & Rehabilitation ScienceNortheastern UniversityBostonUSA

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