TEmPuRA

TEmPuRA: Theory for Electrostriction of PolymeRic ActuatorAxes: Materials & Structure Design, Simulation & ModelingLeaders: Ai SUZUKI (NICHe, TU) & Jean-Yves CAVAILLÉ (ELyTMaX, UL, TU, CNRS)Participants: Nozomu HATAKEYAMA, Ryuji MIURA, Akihira MIYAMOTO(NICHe, TU), Hiroshi YABU (AIMR, TU), Tetsuya UCHIMOTO (IFS, TU), Gael SEBALD, Gildas DIGUET (ELyTMaX), Florent DALMAS (MATEIS, INSA), Jean-Marc CHENAL, Renaud RINALDI (MATEIS, INSA), Jean-Fabien CAPSAL (LGEF, INSA)Conversion of energy is a hot topic in robotics and microfluidics especially in term of electromechanical coupling for actuators and energy harvesting (which includes sensors, useable for non-destructive techniques). Best results are obtained with heterogeneous polymers. Because of the lack of theoretical guideline, they result from a systemic screening, which is time consuming.Up to now, this project analyzed the contribution of dipolar forces created by the electric field variations. More recently, we accounted for the role of conductivity, as the slow mechanical response suggested that diffusion processes should be involved within the physical mechanisms of electrostriction. In addition to these 2 effects (dielectric and conductivity), the space charges should be also taken into account. The project aims at providing a complete model accounting for the electrical properties and the elastic modulus heterogeneities inside the materials. This needs a strong theoretical approach and simulations by molecular dynamics (thanks to the NICHe team) and by Finite Element calculations to reckon the electrical permittivities, conduction and stiffness of each phase. For a given internal architecture, we should predict the electromechanical coupling. Corresponding architectured materials will be fabricated to test the parameters effect.