This paper presents results of a preliminary study of feasibility for the application of electroactive polymer (EAP) based actuators to a robotic locomotion system, intended by the European Space Agency (ESA) to operate on the surface of Mars. The system is conceived as an elastic spherical rover, exploiting wind propulsion for surface motion, while adopting an active mechanism for vertical jumping over obstacles. The use of polymeric electromechanical devices is envisaged in order to provide actuation to such a jumping mechanism. Among the available EAP technologies, new contractile linear actuators based on dielectric elastomers are proposed in this study as suitable devices and two potential solutions concerning their use are designed, modeled, and evaluated via numerical simulations. The best solution reveals interesting simulated performances, enabling jumping of obstacle heights corresponding to more than 7% of the diameter of the rover. © 2007 IEEE

In order to estimate the impact on energy production and environment of tidal turbines placed in or near hydraulic structures like discharge sluices or storm surge barriers, a Computational Fluid Dynamics (CFD) study has been carried out on the relation between (head) loss induced by the turbines and their gross power production. CFD computations have been performed for Tocardo T2 turbines, using STAR-CCM+. Simulations of a single turbine in free flow conditions compare favorably with results of Blade Element Momentum (BEM) computations, in terms of torque and thrust. This BEM method model had been previously validated against both CFD data and field measurements. Then, a series of tests has been performed in a “virtual tow tank”, including the effect of the free surface and the blockage by side and bottom walls. These computations provide a base for a first estimate of the effect of turbines on the discharge capacity of a generic structure. This is considered to be the first step in a more general approach in which ultimately the effect of tidal turbines in the Eastern Scheldt Storm Surge Barrier will be assessed.

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