Skip to content

Design and control of a novel variable stiffness soft arm

Research output: Contribution to journalArticle

Original languageEnglish
Pages (from-to)605-622
Number of pages18
JournalAdvanced Robotics
Issue number11
Early online date30 May 2018
DateAccepted/In press - 25 Apr 2018
DateE-pub ahead of print - 30 May 2018
DatePublished (current) - 3 Jun 2018


Soft robot arms possess such characteristics as light weight, simple structure and good adaptability to the environment, among others. On the other hand, robust control of soft robot arms presents many difficulties. Based on these reasons, this paper presents a novel design and modeling of a fuzzy active disturbance rejection control (FADRC) controller for a soft PAM arm. The soft arm comprises three contractile and one extensor PAMs, which can vary its stiffness independently of its position in space. Force analysis for the soft arm is conducted, and stiffness model of the arm is established based on the relational model of contractile and extensor PAM. The accuracy of stiffness model for the soft arm was verified through experiments. Associated to this, a controller based on the fuzzy adaptive theory and active disturbance rejection control (ADRC), FADRC, has been designed to control the arm. The fuzzy adaptive theory is used to adjust the parameters of the ADRC, the control algorithm has the ability to control stiffness and position of the soft arm. In this paper, FADRC was further verified through comparative experiments on the soft arm. This paper reinforces the hypothesis that FADRC control, as an algorithm, indeed possesses good robustness and adaptive abilities.

    Research areas

  • FADRC, PAM, Soft robot, stiffness modeling, variable stiffness

Download statistics

No data available



  • Full-text PDF (accepted author manuscript)

    Rights statement: This is the accepted author manuscript (AAM). The final published version (version of record) is available online via Taylor & Francis at . Please refer to any applicable terms of use of the publisher.

    Accepted author manuscript, 1 MB, PDF document

    Licence: Other


View research connections

Related faculties, schools or groups