A novel variable stiffness mechanism capable of an infinite stiffness range and unlimited decoupled output motion

Stefan Groothuis (Corresponding Author), Raffaella Carloni, Stefano Stramigioli

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    33 Citations (Scopus)
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    In this paper, a novel variable stiffness mechanism is presented, which is capable of achieving an output stiffness with infinite range and an unlimited output motion, i.e., the mechanism output is completely decoupled from the rotor motion, in the zero stiffness configuration. The mechanism makes use of leaf springs, which are engaged at different positions by means of two movable supports, to realize the variable output stiffness. The Euler–Bernoulli leaf spring model is derived and validated through experimental data. By shaping the leaf springs, it is shown that the stiffness characteristic of the mechanism can be changed to fulfill different application requirements. Alternative designs can achieve the same behavior with only one leaf spring and one movable support pin.
    Original languageEnglish
    Pages (from-to)107-123
    Number of pages17
    Issue number2
    Publication statusPublished - 3 Jun 2014


    • variable stiffness mechanism
    • unlimited motion
    • Leaf spring
    • EWI-24821
    • IR-91363
    • hypocycloid gearing
    • infinite stiffness range
    • METIS-304121

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