Mode interaction induced response flattening in two mechanically coupled micro-resonators

Mode interaction in M/NEMS arouses many interests in enhancing functionality in recent years. In this paper, the dynamics of two mechanically coupled micro-resonators with frequency ratio approximately 1:3 for tuning driving strength is investigated experimentally and analytically. Mode interaction induced three stages of response, i.e., typical Duffing response, large half-flattened response and narrow full-flattened response, of the coupled resonators as driving strength increasing are observed. The amplitude relationship of two resonators for each stage is also obtained. The theoretical study based on the mathematical model successfully explains the previous observations. Almost 1-order enhancement of the amplitude stability in the response flattening range is observed finally, which makes the mechanical coupled micro-resonators brilliant candidate as an amplitude-sensing sensor.