Fard M A, Ishihara T, Inooka H
Graduate School of Information Sciences, Tohoku University, Aobayama 01, 980-8579 Sendai Miyagi, Aoba-ku, Japan.
Biol Cybern. 2004 Jun;90(6):418-26. doi: 10.1007/s00422-004-0489-z. Epub 2004 Jul 29.
A method is proposed for identifying the head-neck complex (HNC) in the seated human body when it is exposed to the trunk horizontal (fore-and-aft) vibration. It is assumed that the HNC only has the anteroposterior (flexion/extension) motion in the sagittal plane. An electrohydraulic vibrator is used as a source of vibration. To generate the trunk horizontal vibration, the trunk of the seated subject is fixed to the seatback. The subjects are exposed to the random vibration at a magnitude of 1.60 ms(-2) rms (root-mean-square) for 50 s. The coherence and frequency response function are then obtained in the frequency range 0.5-3 Hz. The results show that the HNC behavior is quasilinear with a resonance frequency between 1 and 1.4 Hz. Accordingly, a two-dimensional single-inverted pendulum is considered as a model for the HNC. The frequency domain identification method is then used to estimate the unknown parameters, including the HNC viscoelastic and inertia parameters. The model is examined in a time domain using the random vibration. Good agreement is obtained between experimental and simulation results, indicating the reliability of the proposed method.
提出了一种用于识别坐姿人体在受到躯干水平（前后）振动时头颈部复合体（HNC）的方法。假设HNC仅在矢状面内具有前后（屈伸）运动。使用电动液压振动器作为振动源。为了产生躯干水平振动，将坐姿受试者的躯干固定在座椅靠背上。受试者在1.60 ms(-2)均方根（rms）的随机振动下暴露50秒。然后在0.5 - 3 Hz的频率范围内获得相干性和频率响应函数。结果表明，HNC行为为准线性，共振频率在1至1.4 Hz之间。因此，将二维单倒立摆视为HNC的模型。然后使用频域识别方法估计未知参数，包括HNC的粘弹性和惯性参数。使用随机振动在时域中对模型进行检验。实验结果与模拟结果取得了良好的一致性，表明了所提方法的可靠性。
