Dynamic Response Characteristics in Variable Stiffness Soft Inflatable Links

  • Ahmad Ali
  • Kaspar Althoefer
  • Jelizaveta KonstantinovaEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11649)


In soft robotics, there is the fundamental need to develop devices that are flexible and can change stiffness in order to work safely in the vicinity of humans. Moreover, these structures must be rigid enough to withstand the force application and accuracy in motion. To solve these issues, previous research proposed to add a compliance element between motor and load – Series Elastic Actuators (SEAs). This approach benefits from improved force control and shock tolerance due to the elasticity introduced at joint level. However, series compliance at the joint level comes at the cost of inferior position controllability and additional mechanical complexity. In this research, we move the elastic compliance to the link, and evaluate the characteristics of variable stiffness soft inflatable links. The detailed investigation of the dynamic behaviour of inflatable link takes into consideration different internal pressures and applied loads. Our results demonstrate that the use of soft inflatable links leads to good weight lifting capability whilst preserving compliance which is beneficial for safety critical applications.


Dynamic response Variable stiffness Inflatable soft link Human-robot interaction 


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Ahmad Ali
    • 1
  • Kaspar Althoefer
    • 1
  • Jelizaveta Konstantinova
    • 1
    Email author
  1. 1.The Centre for Advanced Robotics @ Queen Mary (ARQ)Queen Mary University of LondonLondonUK

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