The Variable Stiffness Actuator vsaUT-II: Mechanical Design, Modeling, and Identification

Stefan Groothuis, Giacomo Rusticelli, Andrea Zucchelli, Stefano Stramigioli, Raffaella Carloni

    Research output: Contribution to journalArticleAcademicpeer-review

    77 Citations (Scopus)

    Abstract

    In this paper, the rotational variable stiffness actuator vsaUT-II is presented. This actuation system is characterized by the property that the apparent stiffness at the actuator output can be varied independently from its position. This behavior is realized by implementing a variable transmission ratio between the internal elastic elements and the actuator output, i.e., a lever arm with variable pivot point position. The pivot point is moved by a planetary gears mechanism, which acquires a straight motion from only rotations, thereby providing a low-friction transmission. The working principle details of the vsaUT-II are elaborated and the design is presented. The actuator dynamics are described by means of a lumped parameter model. The relevant parameters of the actuator are estimated and identified in the physical setup and measurements are used to validate both the design and the derived model.
    Original languageUndefined
    Pages (from-to)589-597
    Number of pages9
    JournalIEEE/ASME transactions on mechatronics
    Volume19
    Issue number2
    DOIs
    Publication statusPublished - Apr 2014

    Keywords

    • EWI-23359
    • IR-86213
    • METIS-297645
    • CE-Advanced Robotics

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