Coulomb-actuated microbeams revisited: experimental and numerical modal decomposition of the saddle-node bifurcation  

作　　者：Anton Melnikov Hermann A.G.Schenk Jorge M.Monsalve Franziska Wall Michael Stolz Andreas Mrosk Sergiu Langa Bert Kaiser 

机构地区：[1]Fraunhofer Institute for Photonic Microsystems IPMS,Dresden 01109,Germany [2]Arioso Systems GmbH,Dresden 01109,Germany [3]Brandenburg University of Technology Cottbus-Senftenberg,Cottbus 03046,Germany

出　　处：《Microsystems & Nanoengineering》2021年第3期111-123,共13页微系统与纳米工程（英文）

摘　　要：Electrostatic micromechanical actuators have numerous applicati ons in scie nee and technology.In many applications,they are operated in a narrow frequency range close to resonanee and at a drive voltage of low variation.Recently,new applications,such as microelectromechanical systems(MEMS)microspeakers(μSpeakers),have emerged that require operation over a wide frequency and dynamic range.Simulating the dynamic performance under such circumstances is still highly cumbersome.State-of-the-art finite element analysis struggles with pull-in instability and does not deliver the necessary in formation about un stable equilibrium states accordingly.Convincing lumped-parameter models amenable to direct physical interpretation are missing.This inhibits the in dispensable in-depth analysis of the dynamic stability of such systems.In this paper,we take a major step towards mending the situation.By combining the finite element method(FEM)with an arc-length solver,we obtain the full bifurcation diagram for electrostatic actuators based on prismatic Euler-Bernoulli beams.A subsequent modal analysis then shows that within very narrow error margins,it is exclusively the lowest Euler-Bernoulli eigenmode that dominates the beam physics over the entire relevant drive voltage range.An experiment directly recording the deflection profile of a MEMS microbeam is performed and confirms the numerical findings with astonishing precision.This enables modeling the system using a single spatial degree of freedom.

关 键 词：BIFURCATION MODAL NARROW 

分 类 号：O17[理学—数学]