Design of Clutch Mechanism for Increased Actuator Energy Efficiency of Electrically Actuated Lower Extremity Exoskeleton

전기식 하지 외골격 로봇의 구동기 에너지 효율 향상을 위한 클러치 메커니즘 설계

Kim, Ho Jun;Kim, Wan Soo;Lim, Dong Hwan;Han, Chang Soo

  • Received : 2015.08.06
  • Accepted : 2015.11.17
  • Published : 2016.03.01


This paper reports on the development of a roller-cam clutch mechanism. This mechanism can transfer bidirectional torque with high backdrivability, as well as increase actuation energy efficiency, in electrical exoskeleton robots. The developed mechanism was installed at the robot knee joint and unclutched during the swing phase which uses less metabolic energy, thereby functioning as a passive joint. The roller-cam clutch aimed to increase actuation energy efficiency while also producing high backdrivability by generating zero impedance for users during the swing phase. To develop the mechanism, mathematical modeling of the roller-cam clutch was conducted, with the design having more than three safety factors following optimization. Titanium (Ti-6AL-4V) material was used. Finally, modeling verification was done using ANSYS software.


Roller-Cam clutch mechanism;Exoskeleton robot;Backdrivability;Energy efficiency;Design optimization


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Supported by : 한국연구재단