Resonant Loop Design and Performance Test for a Torsional MEMS Accelerometer with Differential Pickoff

  • Sung, Sang-Kyung (Department of Aerospace Information system Engineering, Konkuk University) ;
  • Hyun, Chul (School of Electrical Engineering and Computer Science, Seoul National University) ;
  • Lee, Jang-Gyu (School of Electrical Engineering and Computer Science, Seoul National University)
  • 발행 : 2007.02.28

초록

This paper presents an INS(Inertial Navigation System) grade, surface micro-machined differential resonant accelerometer(DRXL) manufactured by an epitaxially grown thick poly silicon process. The proposed DRXL system generates a differential digital output upon an applied acceleration, in which frequency transition is measured due to gap dependent electrical stiffness change. To facilitate the resonance dynamics of the electromechanical system, the micromachined DRXL device is packaged by using the wafer level vacuum sealing process. To test the DRXL performance, a nonlinear self-oscillation loop is designed based on the extended describing function technique. The oscillation loop is implemented using discrete electronic elements including precision charge amplifier and hard feedback nonlinearity. The performance test of the DRXL system shows that the sensitivity of the accelerometer is 24 Hz/g and its long term bias stability is about 2 mg($1{\sigma}$) with dynamic range of ${\sigma}70g$.

키워드

참고문헌

  1. B. L. Lee, C. H. Oh, Y. S. Oh, and K. Chun, 'A novel resonant accelerometer; Variable electrostatic stiffness type,' Proc. of International Conference on Solid State Sensors and Actuators, Sendai, pp. 1546-1549, 1999
  2. L. Lee, C. H. Oh, S. Lee, Y. S. Oh, and K. Chun, 'A vacuum packaged differential resonant accelerometer using gap sensitive electrostatic stiffness changing effect,' Proc. of the 13th International Conference on MEMS, Miyazaci, pp. 352-357, January 2000
  3. S. Sung, J. G. Lee, T. Kang, and J. W. Song, 'Design and analysis of nonlinear feedback loop for a resonant accelerometer,' Proc. of European Control Conference, Porto, pp. 1906-1911, September 2001
  4. B. L. Norling, 'Superflex: A synergitic combination of vibrating beam and quartz flexure accelerometer,' Journal of the Institute of Navigation, vol. 34, no. 4, pp. 337-353, 1988
  5. D. W. Burns, R. D. Horning, W. R. Herb, J. D. Zook, and H. Guckel, 'Resonant microbeam accelerometer,' Proc. of International Conference on Solid-State Sensors and Actuators (Transducers `95), pp. 659-662, 1995
  6. T. A. Rossig, R. T. Howe, A. P. Pisano, and J. H. Smith, 'Surface-micro-machined resonant accelerometer,' Proc. of International Conference on Solid State Sensors and Actuators (Transducers '97), pp. 869-862, 1997
  7. M. A. Meldrum, 'Application of vibration beam technology to digital acceleration measurement,' Sensor and Actuators, vol. A21-A23, pp. 377-380, 1990
  8. T. V. Roszhart, H. Jerman, J. Drake, and C. de Cotiis, 'An inertial-grade, micromachined vibrating beam accelerometer,' Proc. of the 8th International Conference on Solid-State Transducers and Actuators (Transducers `95), pp. 659-662, 1995
  9. Y. Omura, Y. Nonomura, and O. Tabata, 'New resonant accelerometer based on rigidity change,' Proc. of International Conference on Solid State Sensors and Actuators (Transducers'97), pp. 855-858, 1997
  10. G. S. Krenz and R. K. Miller, 'Qualitative analysis of oscillation in nonlinear control systems: A describing function approach,' IEEE Trans. on Circuits and Systems, vol. 33, no. 5, pp. 562-566, May 1986 https://doi.org/10.1109/TCS.1986.1085943
  11. S. Sung, A Feedback Loop Design for MEMS Resonant Accerlerometer Using a Describing Function Technique, Ph.D. Thesis, Seoul National University, February 2003
  12. J. E. Slotine and W. Li, Applied Nonlinear Control, Prentice-Hall Inc., Englewood Cliffs, New Jersey, 1991