, Volume 50, Issue 11, pp 2797–2813 | Cite as

Model-based design and optimization of a dielectric elastomer power take-off for oscillating wave surge energy converters

  • Giacomo Moretti
  • Marco Fontana
  • Rocco Vertechy
Soft Mechatronics


This paper investigates a new kind of device for producing electricity from the mechanical energy carried by ocean waves. The proposed machine, named poly-surge, is based on an existing sea-bottom hinged surging-flap concept that is equipped with a new power take-off (PTO) system based on a novel soft dielectric elastomer (DE) transducer. DEs are highly deformable polymeric materials that can be used to conceive electrostatic generators relying on capacitance variation. This kind of generators shows a number of features that well match the requirements of a wave energy converter since they are light-weight, low-cost, tolerant to salty/aggressive marine environment, noise-free during operation, and easy to manufacture and install. The considered poly-surge converter employs a parallelogram-shaped DE generator (PS-DEG) arranged in a dual agonist–antagonist configuration, which makes it possible to provide the flap with controllable bidirectional torques. In this paper, first a complete wave-to-wire multiphysics model of the overall system is described that assumes a simplified hydrodynamic response for the hinged-flap and an electro-hyperelastic behaviour of the PS-DEG. Second, a procedure is presented for the dimensioning and optimization of the PS-DEG for given sets of poly-surge flap dimensions, wave-climate information and constraints on both design and operational variables. Finally, simulation results are provided to demonstrate that the poly-surge can achieve quasi-optimal power production with a properly designed agonist–antagonist DEG PTO system.


Wave energy WEC Oscillating wave surge converter Dielectric elastomer Parallelogram-shaped dielectric elastomer generator Smart materials DEG Poly-surge Polymeric PTO 



The work presented in this paper is developed in the context of the project PolyWEC (, a FP7FET-Energy project. The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under Grant Agreement No. 309139. The authors sincerely thank Dr. David Forehand (Edinburgh University) for providing the hydrodynamic outputs from WAMIT, and Eng. Antonello Cherubini (Scuola Sant’Anna, Pisa) for patiently reviewing the manuscript.


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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • Giacomo Moretti
    • 1
  • Marco Fontana
    • 1
  • Rocco Vertechy
    • 2
  1. 1.PERCRO-SEES, TeCIP InstituteScuola Superiore di Studi Universitari e di Perfezionamento Sant’AnnaPisaItaly
  2. 2.Department of Industrial EngineeringUniversity of BolognaBolognaItaly

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