Development of a 2-DOF Ankle Mechanism for Gait Rehabilitation Robots

보행 재활 로봇을 위한 2자유도 족관절 기구 개발

  • Heo, Geun Sub (School of Mechanical Engineering, Kyungpook National University) ;
  • Kang, Oh Hyun (School of Mechanical Engineering, Kyungpook National University) ;
  • Lee, Sang Ryong (School of Mechanical Engineering, Kyungpook National University) ;
  • Lee, Choon-Young (School of Mechanical Engineering, Kyungpook National University)
  • Received : 2015.02.15
  • Accepted : 2015.03.15
  • Published : 2015.06.01


In this paper, we designed and tested an ankle joint mechanism for a gait rehabilitation robot. Gait rehabilitation programs are designed to improve the natural leg motion of patients who have lost their walking capabilities by accident or disease. Strengthening the muscles of the lower-limbs and stimulation of the nervous system corresponding to walking helps patients to walk again using gait assistive devices. It is an obvious requirement that the rehabilitation system's motion should be similar to and as natural as the normal gait. However, the system being used for gait rehabilitation does not pay much attention to ankle joints, which play an important role in correct walking as the motion of the ankle should reflect the movement of the center of gravity (COG) of the body. Consequently, we have designed an ankle mechanism that ensures the safety of the patient as well as efficient gait training. Also, even patients with low leg muscle strength are able to operate the ankle joint due to the direct-drive mechanism without a reducer. This safety feature prevents any possible adverse load on the human ankle. The additional degree of freedom for the roll motion achieves a gait pattern which is similar to the normal gait and with a greater degree of comfort.


Supported by : 미래창조과학부, 한국연구재단


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