Integral indicator of the assessment of the functional state of the “fatigue” of the aircraft pilot

The necessity of timely diagnostics and forecasting of the fl ight crew performance level under the infl uence of a complex of unfavorable factors that reduce the effi ciency of professional activity and disrupt the functional state of pilots is considered. It is shown that the most frequent functional state of “fatigue” occurs in pilots during aircraft control. A method for assessing the functional state of civil aviation pilots has been developed, which is based on determining the value of the integral indicator with subsequent classifi cation of a specifi c stage of the functional state: no fatigue, compensated, acute, chronic, overfatigue. A set of physiological indicators has been determined – heart rate, respiratory rate, fractional blood saturation level and the value of the standard deviation of the duration of cardiointervals – for which a functional dependence for calculating the integral indicator of the functional state has been obtained using the multiple linear regression method. taking into account. It has been shown that preliminary normalization of the values of physiological indicators is carried out using the Harrington membership function. The proposed integral indicator varies within 0–100 %. The reliability of the proposed regression model is statistically substantiated: all regression coeffi cients were confi rmed using the Student's t-test at a signifi cance level of 0.01, and the determination coeffi cient of 0.934 was calculated, confi rming the high level of compliance of the obtained functional dependence with the original data. The proposed integral indicator of the functional state was verifi ed for two control groups of pilots. The calculated pair correlation coeffi cients were 0.842 for the fi rst group and 0.798 for the second group, indicating a strong positive correlation according to Pearson and, consequently, the consistency of the calculated values of the integral indicator of the functional state with expert assessments. The obtained results can be used in the design and development of devices for non-invasive diagnostics of the functional state, as well as in the fi eld of clinical medicine for assessing the values of physiological indicators.

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