Capacitive Charge-based Self-Sensing for Resonant Electrostatic MEMS mirrors

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • 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)

Abstract

This paper proposes capacitive charge-based self-sensing by integration of the comb drive intrinsic displacement current for resonant electrostatic MEMS mirrors in order to solve the problem of robust feedback for laser scanning in mobile light detection and ranging (Lidar) application. A two-channel switched current integrator circuit is implemented to determine the deflection angle and to distinguish the rotation direction from the asymmetric comb drive charge. Parameters of the MEMS mirror are calibrated with the deflection angle by an optical PSD setup. The resonant electrostatic MEMS mirror is parametrically driven by a square wave high voltage signal, which means, that the charge measurement is only available during the time with non-zero drive signal. From the partly available charge measurements, a nonlinear observer is developed to estimate the mirror state at all time for a potential feedback control. The feasibility for online position estimation is proven by simulation using experimental charge and deflection angle measurements resulting in less than 2 % error at full amplitude operation. Finally, the performance of the proposed method is discussed for realization of active MEMS mirror feedback control, overcoming imprecise motions due to structural nonlinearities as well as external disturbances like vibration and climate variation. Copyright (C) 2020 The Authors.

Details

Original languageEnglish
Pages (from-to)8553-8558
Number of pages6
Journal IFAC-PapersOnLine
Volume53
Issue number2
Publication statusPublished - 2020
Peer-reviewedYes
Externally publishedYes

Conference

Title21st World Congress of the International Federation of Automatic Control
SubtitleAutomatic Control – Meeting Societal Challenges
Abbreviated titleIFAC 2020
Conference number21
Duration12 - 17 July 2020
Locationonline
CityBerlin
CountryGermany

External IDs

Scopus 85101544562
ORCID /0000-0003-3259-4571/work/142249647

Keywords

Sustainable Development Goals

Keywords

  • Resonant MEMS mirror, electrostatic comb drive, capacitive charge sensing, nonlinear observer with switched input