Numerical modeling of a MEMS actuator considering several magnetic force calculation methods
Creators: name: Preisner, Thomas
name: Bolzmacher, Christian
name: Gerber, Andreas
name: Bauer, Karin
name: Quandt, Eckhard
name: Mathis, Wolfgang
Publisher: name: Bingley : Emerald Group Publishing Ltd.
Year: 2011
Subjects: subject: Actuators
subject: Force measurement
subject: Mems
subject: Acting force
subject: Design/methodology/approach
subject: Element method
subject: Force calculation
subject: Hybrid approach
subject: Laboratory measurements
subject: Magnetic field evaluations
subject: Magnetic force
subject: Magnetic sources
subject: Magnetomechanical couplings
subject: Maxwell stress tensors
subject: Measurement data
subject: Mechanical behavior
subject: Mechanical deformation
subject: MEMS actuators
subject: Normal forces
subject: Numerical approaches
subject: Numerical modeling
subject: Research limitations
subject: Tangential force
subject: Virtual works
subject: Deformation
subject: Finite element method
subject: Magnetic fields
subject: Measurements
subject: MEMS
subject: Micrometers
subject: Stresses
subject: Numerical methods
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau
subject: Dewey Decimal Classification::500 | Naturwissenschaften::510 | Mathematik

description: Purpose: The purpose of this paper is to investigate the accuracy of different force calculation methods and their impact on mechanical deformations. For this purpose, a micrometer scaled actuator is considered, which consists of a micro-coil and of a permanent magnet (PM) embedded in a deformable elastomeric layer. Design/methodology/approach: For the magnetic field evaluation a hybrid numerical approach (finite element method/boundary element method (FEM/BEM) coupling and a FEM/BEM/Biot-Savart approach) is used, whereas FEM is implemented for the mechanical deformation analysis. Furthermore, for the magneto-mechanical coupling several force calculation methods, namely the Maxwell stress tensor, the virtual work approach and the equivalent magnetic sources methods, are considered and compared to each other and to laboratory measurements. Findings: The numerically evaluated magnetic forces and the measured ones are in good accordance with each other with respect to the normal force acting on the PM. Nevertheless, depending on the used method the tangential force components differ from each other, which leads to slightly different mechanical deformations. Research limitations/implications: Since the force calculations are compared to measurement data, it is possible to give a suggestion about their applicability. The mechanical behavior of the actuator due to the acting forces is solely calculated and therefore only an assumption concerning the deformation can be given. Originality/value: A new kind of micrometer scaled actuator is numerically investigated by using two different hybrid approaches for the magnetic field evaluation. Based on those, the results of several force calculation methods are compared to measurement data. Furthermore, a subsequent structural analysis is performed, which shows slightly different mechanical deformations depending on the used force calculation method. © Emerald Group Publishing Limited.