Self-sensing control of resonant MEMS scanner by comb-drive current feedback


          

刊名:Mechatronics: The Science of Intelligent Machines
作者:Brunner, David(TU Wien, Automat & Control Inst ACIN, Gusshausstr 27-29, A-1040 Vienna, Austria)
Albert, Stephan(Infineon Technol AG, Neubiberg, Germany)
Hennecke, Marcus(Infineon Technol Austria AG, Graz, Austria)
Darrer, Franz(Infineon Technol Austria AG, Graz, Austria)
Schitter, Georg(TU Wien, Automat & Control Inst ACIN, Gusshausstr 27-29, A-1040 Vienna, Austria)
刊号:736C0117
ISSN:0957-4158
出版年:2021
年卷期:2021, vol.78
总页数:8
分类号:TN0
关键词:Micro-electro-mechanical system (MEMS)Nonlinear systemsPhase locked loop (PLL)Precision controlResonant scanning mirrorSelf-sensing
参考中译:
语种:eng
文摘:This paper proposes a novel self-sensing control concept for resonant MEMS mirrors solely based on the comb-drive current generated by the mirror movement and simple circuitry. Phase errors are immediately compensated by asynchronous switching of the driving voltage using the precise zero crossing detection by the steep current gradient. The mirror amplitude is detected based on the time difference between a comparator threshold crossing of the current signal and the zero crossing of the mirror, while it is controlled by the duty cycle of the driving voltage signal. The proper threshold setting is analyzed regarding the obtained sensitivity and uncertainty of the amplitude detection and is verified by measurements. It is found that even for symmetric out-of-plane comb-drives the scanning direction can be determined utilizing the mode coupling phenomenon of a lightweight MEMS mirror design with reinforcement structure. Experiments show that the proposed control concept results in a low optical pointing uncertainty of 0.52 mdeg, which allows 10 000 pixels with a precision of 10 sigma at a scanning frequency of 2kHz. Thus a lightweight and simple design of a high performance MEMS mirror is precisely controlled in its oscillation without any additional sensors or complex circuitry.