Charge-Based Capacitive Self-Sensing With Continuous State Observation for Resonant Electrostatic MEMS Mirrors

Research output: Contribution to journalResearch articleContributedpeer-review


  • Richard Schroedter - , Vienna University of Technology (Author)
  • Han Woong Yoo - , Vienna University of Technology (Author)
  • David Brunner - , Vienna University of Technology (Author)
  • Georg Schitter - , Vienna University of Technology (Author)


This contribution presents charge-based capacitive self-sensing with a continuous full state observer for a parametrically driven resonant electrostatic 1D MEMS mirror considering precise and seamless estimation. Based on current integrators, series capacitances or a capacitance network the direct charge self-sensing principles are investigated and compared considering leakage currents, precision and a minimum implementation effort. In comparison to the other charge sensing methods, the proposed methods directly measure the charge changes while the drive voltage is switched on. Since resonant MEMS mirrors are driven by a rectangular signal, the direct self-sensing implies a lack of data when the drive voltage is switched off. A nonlinear observer is also proposed to estimate the full mirror state continuously based on an identified MEMS mirror model. The capacitive charge self-sensing methods achieve overall a high sensing precision of less than 0.14 % RMSE and the observer estimation error of the full state is below 1 % peak-to-peak error regardless of the availability of the charge self-sensing measurements, demonstrates accurate continuous full state estimation. [2021-0130]


Original languageEnglish
Pages (from-to)897-906
Number of pages10
Journal Journal of microelectromechanical systems : JMEMS
Issue number6
Publication statusPublished - Dec 2021
Externally publishedYes

External IDs

Scopus 85120822105
ORCID /0000-0003-3259-4571/work/142249644



  • Capacitance, Sensors, Mirrors, Micromechanical devices, Voltage measurement, Observers, Electrostatics, Charge-based capacitive self-sensing, resonant MEMS mirror, electrostatic comb drive, switched current integrator, capacitance network, nonlinear switched input Luenberger observer