Shock Absorber Mechanism Based on an SMA Spring for Lightweight Exoskeleton Applications

  • Seungjun Lee
  • Sanghee Lee
  • Youngjin Na
  • Bummo Ahn
  • Hoeryong Jung
  • Shing Shin Cheng
  • Namkeun Kim
  • Tea-Sung Jun
  • Yeongjin KimEmail author
Regular Paper


Wearable exoskeletons have generally been designed to enhance user strength or to reduce user fatigue. Two areas that have often been overlooked are that exoskeletons should increase user safety and have increased durability for use in extreme environments. In this paper, we developed an SMA spring-based shock absorption module for an exoskeleton or a quadruped walking robot, which can provide increased protection to the user during high-impact events in an extreme environment. We analyzed the impact force during the collision between the module and the ground based on impulse and momentum theories. The shock absorber module can be reused by exploiting the inherent shape memory characteristics of the SMA spring after every use. We confirmed that the spring constant of the SMA spring and the maximum allowable length affect the impulse reduction, and the results showed that the latter has a greater influence on impulse reduction.


Robotic rehabilitation Exoskeleton Shock absorber SMA spring Plastic deformation 



This work was supported by Incheon National University Research Grant in 2016.


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Copyright information

© Korean Society for Precision Engineering 2019

Authors and Affiliations

  • Seungjun Lee
    • 2
  • Sanghee Lee
    • 2
  • Youngjin Na
    • 3
  • Bummo Ahn
    • 4
  • Hoeryong Jung
    • 5
  • Shing Shin Cheng
    • 6
  • Namkeun Kim
    • 1
    • 2
  • Tea-Sung Jun
    • 2
  • Yeongjin Kim
    • 1
    • 2
    Email author
  1. 1.Division of Thermal and Fluids Science, Institute for Computational Science, Faculty of Electrical and Electronics EngineeringTon Duc Thang UniversityHo Chi Minh CityVietnam
  2. 2.Department of Mechanical EngineeringIncheon National UniversityIncheonKorea
  3. 3.Department of Mechanical Systems EngineeringSookmyung Women’s UniversitySeoulKorea
  4. 4.Robotics R&BD GroupKorea Institute of Industrial TechnologyGyeonggi-doKorea
  5. 5.Department of Mechanical EngineeringKonkuk UniversitySeoulKorea
  6. 6.Department of Mechanical and Automation EngineeringThe Chinese University of Hong KongShatinHong Kong

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