Experimental Evidence of Mechanical Frequency Comb in a Quad-Mass Mems Structure

Challenging applications and the increasing request of higher performances of MEMS devices are focusing the attention of the MEMS community on the understanding and modelling of complex dynamic phenomena. In this work, we experimentally detect a mechanical frequency comb arising in a quad-mass MEMS structure electrostatically actuated through comb fingers electrodes and we propose a simplified model able to predict such nonlinear dynamic behaviour. In particular, we hypothesize a 1:3 internal resonance between two in-plane modes of the structure and exhibit the presence of a Neimark-Sacker bifurcation responsible of frequency comb phenomena.