This work proposes a self-sensing method for a synchronous electrostatic film motor. The method utilizes the relation between the driving voltages and currents of the motor. Through several signal conversions on the measured motor currents, the system distills the information of the slider position to realize displacement sensing. The resulting system can track the slider position both for synchronous and non-synchronous operations. The system assumes stepwise motions of the slider and fully exploits the characteristic current features of the motions. Two different signal conversion methods have been tested using numerically simulated motor currents and real motor currents. The two methods differ in terms of accuracy and noise immunity. Considering that the currents of the electrostatic motor are relatively small, the method with high noise immunity and relatively low accuracy was found useful for practical applications. The position resolution achieved by the method was in the order of the electrode pitch, which is 200 μm in the prototype motor used in this work.
TrimmerW. and GabrielK., Design considerations for a practical electrostatic micro-motor, Sensors and Actuators11(2) (1987), 189–206.
2.
FanL.-S.TaiY.-C. and MullerR. S., Ic-processed electrostatic micro-motor, in: IEDM. Tech. Dig., IEEE, 1988, pp. 666–669.
3.
TaiY.-C.FanL.-S. and MullerR. S., Ic-processed micro-motors: Design, technology, and testing, in: Proc. IEEE MEMS, 1989, pp. 1–6.
4.
YamashitaN.ZhangZ. G.YamamotoA.GondoM. and HiguchiT., Voltage-induction type electrostatic film motor driven by two-to four-phase ac voltage and electrostatic induction, Sensors and Actuators A: Physical140(2) (2007), 239–250, doi:10.1016/j.sna.2007.07.007.
5.
HosobataT.YamamotoA. and HiguchiT., An electrostatic induction motor utilizing electrical resonance for torque enhancement, Sensors and Actuators A: Physical173(1) (2012), 180–189, doi:10.1016/j.sna.2011.10.014.
6.
YamashitaN.YamamotoA. and HiguchiT., Pulse voltage operation of two-to-four-phase voltage-induction-type electrostatic motor, International Journal of Applied Electromagnetics and Mechanics42(3) (2013), 391–408, doi:10.3233/JAE-131672.
7.
HosobataT.YamamotoA. and HiguchiT., Transparent synchronous electrostatic actuator for long-stroke planar motion, IEEE/ASME Transactions on Mechatronics20(4) (2015), 1765–1776, doi:10.1109/TMECH.2014.2353815.
8.
NiinoT.EgawaS. and HiguchiT., High-power and high-efficiency electrostatic actuator, in: Proc. IEEE MEMS, 1993, pp. 236–241.
9.
NiinoT.HiguchiT. and EgawaS., Dual excitation multiphase electrostatic drive, in: Proc. IEEE IAS'95, Vol. 2, 1995, pp. 1318–1325.
10.
NishijimaT.YamamotoA.HiguchiT. and InabaA., Fabrication of robot arm using electrostatic film actuator, in: Proceedings of SICE SI2002, Vol. 1, 2002, pp. 45–46. (in Japanese).
11.
HosobataT. and YamamotoA., Mixed reality system on flat panel display with real object driven by synchronous transparent electrostatic actuator, in: Proc. Int. Conf. Multimedia Human Comput. Interaction, 2013, p. 127–1.
12.
WangH.YamamotoA. and HiguchiT., Electrostatic-motor-driven electroadhesive robot, in: IEEE/RSJ IROS, 2012, pp. 914–919.
13.
NiinoT.EgawaS.NishiguchiN. and HiguchiT., Development of an electrostatic actuator exceeding 10 n propulsive force, in: Proc. IEEE MEMS'92, 1992, pp. 122–127.
14.
YamamotoA.NiinoT. and HiguchiT., A high-power electrostatic linear servo motor, Proc. Linear Drives for Industry Applications98 (1998), 212–215.
15.
NishijimaT.YamamotoA.YasuiH. and HiguchiT., A built-in displacement sensor for an electrostatic film motor, Measurement Science and Technology17(10) (2006), 2676, doi:10.1088/0957-0233/17/10/020.
16.
KulkarniA. B. and EhsaniM., A novel position sensor elimination technique for the interior permanent-magnet synchronous motor drive, IEEE Transactions on Industry Applications28(1) (1992), 144–150.
17.
SungJ. W.LeeC. W.KimG.-S.LipoT.WonC.-Y. and ChoiS., Sensorless control for linear compressors, International Journal of Applied Electromagnetics and Mechanics24(3–4) (2006), 273–286.
18.
QiaoZ.ShiT.WangY.YanY.XiaC. and HeX., New sliding-mode observer for position sensorless control of permanent-magnet synchronous motor, IEEE Transactions on Industrial Electronics60(2) (2013), 710–719, doi:10.1109/TIE.2012.2206359.
19.
BuW.HuangY.LiZ.ShiH. and ShiJ., Diaplacement sensorless control strategy of bearingless induction motor, International Journal of Applied Electromagnetics and Mechanics54(4) (2017), 597–610, doi:10.3233/JAE-160146.
20.
UzelD.PeroutkaZ.ŠmídlV.KošanT. and ZemanK., Self-sensing control of wound rotor synchronous motor drive for mine hoist, IEEE Transactions on Industrial Electronics65(3) (2018), 2009–2017, doi:10.1109/TIE.2017.2740818.
21.
ZhangG. and YamamotoA., Toward self-sensing of an electrostatic film motor using driving currents, in: IEEE ICIT, 2018, pp. 551–556.
22.
YamamotoA.NiinoT. and HiguchiT., Modeling and identification of an electrostatic motor, Precision Engineering30(1) (2006), 104–113, doi:10.1016/j.precisioneng.2005.06.004.
23.
AkinB. and BhardwajM., Sensored field oriented control of 3-phase induction motors, in: Texas Instrument Guide, 2013.
24.
ItohK., Analysis of the phase unwrapping algorithm, Applied Optics21(14) (1982), 2470–2470.
25.
GdeisatM. and LilleyF., One-dimensional phase unwrapping problem, Signal4 (2016), 6.
