Journal of Sensor Science and Technology (센서학회지)

The Korean Sensors Society (한국센서학회)
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Micro-Machined Capacitive Linear Encoder with a Mechanical Guide

마이크로 머시닝으로 제작한 기계적 가이드를 갖는 정전용량 선형 인코더

  • 강대실 (포항공과대학 기계공학과) ;
  • 문원규 (포항공과대학 기계공학과)
  • Received : 2012.09.21
  • Accepted : 2012.11.19
  • Published : 2012.11.30
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Abstract

Contact-type Linear Encoder-like Capacitive Displacement Sensor (CLECDiS) is a novel displacement sensor which has wide measurable range with high resolution. The sensor, however, is very sensitive to relative rotational alignment between stator and mover of the sensor as well as its displacement. In addition to, there can be some disturbances in the relative rotational alignment, so some noises occur in the sensor's output signal by the disturbances. This negative effect of the high sensitivity may become larger as increasing sensitivity. Therefore, this negative effect of the high sensitivity has to be compensated and reduced to achieve nanometer resolution of the sensor. In this study, a new type capacitive linear encoder with a mechanical guide is presented to reduce the relative rotational alignment problem. The presented method is not only to reduce the alignment problem, but also to assemble the sensor to the stage conveniently. The method is based on a new type CLECDiS that has mechanical guide autonomously. In the presented sensor, when the device is fabricated by micro-machining, the guide-rail is also fabricated on the surface of the sensor. By the direct fabrication of the guide-rail with high precision micro-machining, errors of the guide-rail can be reduced significantly. In addition, a manual yaw alignment is not required to obtain large magnitude of the output signal after the assembly of the sensor and the stage. The sensor movement is going to follow the guide-rail automatically. The prototype sensor was fabricated using the presented method, and we verify the feasibility experimentally.

Keywords

Acknowledgement

Supported by : 한국연구재단, 국방과학연구소

References

  1. A. A. Kuijpers, G. J. M. Krijnen, R. J. Wiegerink, T. S. J. Lammerink, and M. Elwenspoek, "A micromachined capacitive incremental position sensor : part 2. Experimental assessment", Journal of Micromechanics and Microengineering, Vol. 16, pp. pp. S125-S134, 2006. https://doi.org/10.1088/0960-1317/16/6/S19
  2. A. A. Arkadan, S. Subramaniam, Sivanesan, O. Douedari. "Design optimization of a capacitive transducer for displacement measurement", IEEE Transactions on Magnetics, Vol. 35, pp. 1869-1872, 1999. https://doi.org/10.1109/20.767398
  3. F. Zhu, and J. W. Spronck, "A capacitive tactile sensor for shear and normal force measurements", Sens. Actuators A, Vol. 31, pp. 115-120, 1992. https://doi.org/10.1016/0924-4247(92)80089-L
  4. F. Zhu, and J. W. Spronck. "A simple capacitive displacement sensor", Sens. Actuators A, Vol. 25-27, pp. 265-269, 1991.
  5. W. C. Heerens, "Application of capacitance techniques in sensor design", Journal of Physics E: Scientific Instruments, Vol. 19, pp. 897-906, 1986. https://doi.org/10.1088/0022-3735/19/11/002
  6. M. Hirasawa, M. Nakamura, and M. Kanno, "Optimum from of capacitive transducer for displacement measurement", IEEE Transactions on Instrumentation and Measurement, Vol. IM-33, pp. 276-280, 1984.
  7. A. A. Kuijpers, "Micromachined capacitive longrange displacement sensor for nano positioning of microactuator systems". Ph.D. Enshede: University of Twente. p. 208, 2004.
  8. D. S. Kang, M. J. Kim, and W. K. Moon. "Optimization of a capacitive sensor for high dynamic range", J. Sensor Sci. & Tech., Vol. 19, No. 2, pp. 92-98, 2010. https://doi.org/10.5369/JSST.2010.19.2.092
  9. M. J. Kim and W. K. Moon "A new capacitive displacement sensor for high accuracy and long range", J. Sensor Sci. & Tech., Vol. 14, No. 4, pp. 219-224, 2005. https://doi.org/10.5369/JSST.2005.14.4.219
  10. M. Kim, W. Moon, E. Yoon, and K-R Lee, "A new capacitive displacement sensor with high accuracy and long-range", Sens. Actuators A, Vol. 130-131, pp. 135-141, 2006. https://doi.org/10.1016/j.sna.2005.12.012
  11. M. Kim, W. Moon, W. Chung. "Capacitive motor sensor". US. p. 13, 2006.
  12. M. Kim and W. Moon "A new linear encoder-like capacitive displacement sensor", Measurement, Vol. 39, pp. 481-489, 2006. https://doi.org/10.1016/j.measurement.2005.12.012
  13. S. Kim, W-G Lee, and W-K Moon, "Developing an instrument ensuring reliable contact conditions for contact-type area-varying capacitive displacement sensors", Transactions of the Korean Society of Mechanical Engineers B, Vol. 35, pp. 1147-1156, 2011. https://doi.org/10.3795/KSME-B.2011.35.11.1147
  14. D. Kang, "Improvement of high dynamic range capacitive displacement sensor by a globalm planarization", Journal of Sensor Technology, Vol. 1, pp. 99-107, 2011. https://doi.org/10.4236/jst.2011.14014
  15. L. M. Sanchez-Brea and T. Morlanes, "Metrological errors in optical encoders", Measurement Science and Technology, Vol. 19, p. 115104, 2008. https://doi.org/10.1088/0957-0233/19/11/115104

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