The Journal of the Acoustical Society of Korea

The Acoustical Society of Korea (한국음향학회)
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Effects of Angular Velocity Components on Head Vibration Measurements

각속도 성분들이 머리진동 측정치에 미치는 영향

  • Park Yong Hwa (Acoustics and Vibration Group Korea Research Institute of Standards and Science (KRISS)) ;
  • Cheung Wan Sup (Acoustics and Vibration Group Korea Research Institute of Standards and Science (KRISS))
  • Published : 2005.03.01
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Abstract

This paper addresses issues encountered in measuring the general, 6-degree-of-freedom motion of a human head, A complete mathematical description for measuring the head motion using the six-accelerometer configured bite-bar is suggested, The description shows that the six-axis vibration cannot be completely obtained without the roll, pitch and yaw angular velocity components, A new method of estimating the three orthogonal (roll, pitch and yaw) angular velocities from the six acceleration measurements is introduced. The estimated angular velocities are shown to enable further quantitative error analysis in measuring the translational and angular accelerations at the head. To make this point clear, experimental results are also illustrated in this paper. They show that when the effects of angular velocities are neglected in the head vibration measurement the maximum percentage errors were observed to be more than $3 \%$ for the angular acceleration of the head and to be close to $5 \%$ for its translational acceleration, respectively. It means that the inclusion of all the angular velocity dependent acceleration components gives more accurate measurement of the head vibration.

Keywords

References

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