COMPDYN 2015 5 th ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering M. Papadrakakis, V. Papadopoulos, V. Plevris (eds.) Crete Island, Greece, 25–27 May 2015 PRESTRESS TUNING OF THE NONLINEAR DYNAMICS OF TENSEGRITY METAMATERIALS F. Fraternali 1 , A. Amendola 1 , E. Hern´ andez-Nava 2 , R. Goodall 2 , R.E. Skelton 3 and V.F. Nesterenko 3 1 Department of Civil Engineering, University of Salerno, 84084, Fisciano (SA), Italy e-mail: {f.fraternali, adaamendola1}@unisa.it (A. Amendola, F. Fraternali) 2 Department of Materials Science and Engineering, University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK e-mail: {mtq10eh, r.goodall}@sheffield.ac.uk (E. Hern´ andez-Nava, R. Goodall) 3 University of California San Diego, MAE/Aero, 9500 Gilman Dr., La Jolla, CA 92093, USA e-mail: {bobskelton, vnesterenko}@ucsd.edu (R.E. Skelton, V.F. Nesterenko) Keywords: Tensegrity Prisms, Additive Manufacturing, Electron Beam Melting, Nonlinear Response, Mechanical metamaterials. Abstract. We investigate the experimental response of additively manufactured tensegrity prisms under compression loading and different states of internal prestress. Physical models of tensegrity prisms are additively manufactured through an electron beam melting facility. Spectra strings are applied to the 3D printed models through a post-tensioning approach, which endows the structure with the desired prestress. Experimental tests highlight that the examined structures exhibit strongly nonlinear mechanical response under compression, which appears to be useful for the construction of a new class of nonlinear mechanical metamaterials featuring solitary wave dynamics to be controlled by internal and external prestress. 1960