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A Switching Notch Filter for Reducing the Torque Ripple Caused by a Harmonic Drive in a Joint Torque Sensor

하모닉 드라이브의 토크리플 감소를 위한 조인트 토크센서용 스위칭 노치필터

  • 김준홍 (고려대학교 기계공학부) ;
  • 김영렬 (고려대학교 기계공학부) ;
  • 송재복 (고려대학교 기계공학부)
  • Received : 2010.08.10
  • Accepted : 2011.04.26
  • Published : 2011.07.01

Abstract

Harmonic drives have been widely used in combination with joint torque sensors in order to facilitate accurate manipulator control. A harmonic drive causes a torque ripple because of its structural characteristics, and this torque ripple tends to deteriorate the performance of a controller or observer that uses torque sensors. This paper proposes a switching notch filter for reducing the torque ripple caused by a harmonic drive in a joint torque sensor; the functioning of this filter is based on the relationship between the frequency components of the torque ripple and the rotational velocity of the harmonic drive. The proposed switching notch filter is advantageous in that it requires less computational load and does not necessitate additional circuits or structures. Various experiments demonstrate that the proposed filter has good filtering performance, fast response, and good switching stability.

Keywords

Torque Ripple;Joint Torque Sensor;Switching Notch Filter;Harmonic Drive

References

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