Transmission of Sinusoidally Changing Vertical Specific Force to the Heads of Seated Men Measured in a Flight Simulator

摘要

Modulus and phase lag of the transmission of vertical specific force between a flight simulator moving base and the heads of 10 male seated subjects were measured over a frequency range of 0.1 to 9 Hz. Subjects were seated unrestrained in a normal relaxed position in a pilot seat with or without seat cushions. Although there is scatter among subjects, prominent peaks at around 1.5, 6, and 10 Hz are found for the case without seat cushions. The presence of seat cushions tends to cause a single larger peak in the modulus at around 4 to 5 Hz, and a larger phase lag at higher frequencies. A modulus close to unity and no phase lag are found both with and without seat cushions at frequencies below 1 Hz. It is difficult to read cockpit instruments in the frequency range 4 to 8 Hz.