Publisher : The Korean Society for Aeronautical & Space Sciences
DOI : 10.5139/IJASS.2014.15.3.293
Title & Authors
Study on Vertical Dynamics Compensation for Wobbling Effect Mitigation of Electrostatically Levitated Gyroscope Lee, Jongmin; Song, Hyungmin; Sung, Sangkyung; Kim, Chang Joo; Lee, Sangwoo;
We present a study of vertical dynamics control of an electrostatically levitated gyro-accelerometer considering the wobbling effect and propose a tilt stabilization method with newly introduced control electrodes. Typically, a rotor in a vacuum rotates at high velocity, which may create a drift rate and lead to displacement instability due to the tilt angle of the rotor. To analyze this, first we set up a vertical dynamic equation and determined simulation results regarding displacement control. After deriving an equation for drift dynamics, we analyzed the drift rate of the rotor and the wobbling effect for displacement control quantitatively. Then, we designed new sub-electrodes for moment control that will decrease the drift amplitude of wobbling dynamics. Finally, a simulation study demonstrated that the vertical displacement control with the wobbling compensation electrodes mitigated the rotor`s drift rate, showing the effectiveness of the newly proposed control electrodes.
Q. J. Xiao, W. Y. Chen, G. Ma, F. Cui, S. Y. Li, and W. P. Zhang, "Simulation of Levitation Control for a Micromachined Electrostatically Levitated Gyroscope," IEEE-NEMS 2009, January 2009, pp. 160-163.
L. Yan-zhu, and X. Yun, "Drift Motion of Free-Rotor Gyroscope with Radial Mass-Unbalance," Applied Mathematics and Mechanics, vol. 25, July 2004, pp. 786-791.
R. Houlihan, and M. Kraft, "Modelling of an accelerometer based on a levitated proof mass," Journal of Micromechanics and Microengineering, vol. 12, May 2002, pp. 1-8.
F. Han, Q. Wu, and R. Zhang, "Modeling and Analysis of a Micromotor with an Electrostatically Levitated Rotor," Chinese Journal of Mechanical Engineering, vol. 22, No. 1, February 2009.
T. Murakoshi, Y. Endo, K. Fukatsu, S. Nakamura, and M. Esashi, "Electrostatically Levitated Ring-Shaped Rotational-Gyro/Accelerometer," Japanese Journal of Applied Physics, vol. 42, April 2003, pp. 2468-2472.
B. Damrongsak, M. Kraft, S. Rajgopal, and M. Mehregany, "Design and fabrication of a micromachined electrostatically suspended gyroscope," Proceddings of the Institution of Mechanical Engineers Part C-Journal of Mechanical Engineering Science, vol. 222, June 2007, pp. 53-63.
M. V. Gindila, and M. Kraft, "Electronic interface design for an electrically floating micro-disc," Journal of Micromechanics and Microengineering, vol. 13, June 2003, pp. 11-16.
F. L. WALKER, "An Automatic Gyro Mass-Unbalance Measuring Technique," IEEE Transactions on Military Electronics, vol. 7, Jan 1963, pp. 36-40.
B. Damrongsak, "Development of a Micromachined Electrostatically Suspended Gyroscope", Doctoral Thesis, School of Electronics and Computer Science, University of Southampton, Apr 2009.