Enhanced broadband generator of dual buckled beams with simultaneous translational and torsional coupling

Highlights: • Translational and torsional coupling mechanisms are integrated in a single generator. • A synchronized mechanism of dynamics between multiple degrees of freedom is realized. • Power and bandwidth are boosted to 500% and 150% of the non-coupling case. • The working time of the sensor node gets longer by 40% around with coupling effects. -- Abstract: Introducing coupling effects to the nonlinear generator with multiple degrees of freedom is possible to further improve its bandwidth and power to some extent. However, due to the lack of synchronization mechanism, the dynamics of multiple degrees of freedom are inclined to interfere with each other. It hinders the desired high-energy motions and the performance is thus limited. In order to address this issue, a novel translationally and torsionally coupled generator of two degrees of freedom is proposed by putting two buckled beams on common elastic supports. In contrast with the magnetically-coupled approach in convention, a synchronization mechanism has been elaborated between the two buckled beams corresponding to two degrees of freedom with the help of both translational and torsional coupling. Stable high-energy motions can be obtained without interference over a wide frequency range and the two beams reach a stable synchronized status. Investigations show that the bandwidths of the two buckled beam are increased by 20% and 50% separately. Moreover, the total power performance is enhanced to 500% in comparison with the original case of no coupling. Conducted application evaluations imply that the translational and torsional coupling effects improve the power level, which can afford a higher load situation of the temperature and humidity sensor with 40% longer working time for monitoring environment of metro system.