ねじり振動を受ける立位状態の人体の応答

抄録

Dynamic response of standing human body excited torsionally is investigated. A human body standing on a twisting floor is excited torsionally with frequency 0 ～ 4 Hz. The angular displacements of chest and waist of the human body are measured by optical position sensors. It is found from measured results that standing body of human has two resonance points near about 1 Hz and 2 Hz. Standing human body is modelized as a two degree-of-freedom torsional vibratory system, and system parameters are identified by using measured data. In the identification, mass moment of inertia is estimated from mass distribution of human body, and it is assumed that the response of human body has a dead time component. Stiffness and damping coefficients are identified by least-square method. Another experiment in which additional mass is attached to chest and waist is conducted, and influence of change the mass moment of inertia is investigated. It is found from the another experiment that the stiffness of upper and lower parts of human body are changed as the change the mass moment of inertia, and the resonance frequencies are kept almost constant. Damping property of human body has similar tendency to the stiffness.