Vibration annoyance due to turbulences in an airplane : subjective and physiological assessments

Turbulence phenomena in an aircraft create important vibrations, at frequencies of between 0.5 and 10 Hz. An experimental design was used to assess the influence of different signal parameters (frequency band, vertical and lateral vibration levels), and the task the participant in which the participant was involved (resting, watching a movie on a tablet computer, working by typing and using the trackpad of a computer). Thirty-three participants were subjected to around twenty signals, each lasting 45 s, using a multi-directional excitation device available in Airbus facilities. Physiological parameters (electrodermal activity, heart rate) were measured continuously. After each signal, the participant was asked to assess the discomfort of the situation. The results showed the influence of different signal characteristics or task assigned to the participant. As a general rule, subjective assessments correspond to physiological measurements. The experiment revealed the influences of the signals physical factors and the task performed by the participant. Finally, the ISO2631 standard seems to provide a good representation of the subjective evaluation of discomfort in the different configurations presented.