Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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A New Error Compensation Method in Linear Encoder Using a Phase-Modulated Grating

위상 변환 격자를 이용한 선형 엔코더의 오차 보상법

  • Song, Ju-Ho ;
  • Kim, Gyeong-Chan (Dept. of Mechanical Engineering, Korea Advanced Institute of Science and Technology) ;
  • Kim, Su-Hyeon (Dept. of Mechanical Engineering, Korea Advanced Institute of Science and Technology) ;
  • Gwak, Yun-Geun (Dept. of Mechanical Engineering, Korea Advanced Institute of Science and Technology)
  • Published : 2000.10.01
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Abstract

A new hardware compensation method reducing displacement measurement errors, caused by tilt of index scale in moire linear encoders, has been developed. In conventional moire linear encoders, the detectors are aligned perpendicular to the line of moire fringes this structure is very sensitive to an unwanted tilt of the gratings. In this paper, a newly designed grating, called a phase-modulated grating, is developed to compensate for non-orthogonal errors. By using the phase-modulated grating instead of a conventional index, it is possible to reduce non-orthogonal errors of moire linear encoders.

Keywords

References

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