Analysis of Critical Hazardous State of Vehicle Braking Under Sand Accumulation Situation

Existing research on road safety mainly focuses on normal driving conditions, and seldom considers the impact of poor environment on driving safety. This study focuses on the braking safety of vehicles under sandy road conditions, combines the theories of traffic engineering and cardiophysiology, Through the real vehicle test, the cardiophysiological data of drivers braking under different conditions (including different road alignment, different braking speeds, and different road sand thicknesses) are collected, and the average of the heart rate growth rate and EEG data are analyzed in the process of braking, so as to determine the critical hazardous state of the braking under the condition of sandy roads. The results of the study show that: under different road linear conditions, braking in the combined section of curved slopes is the most dangerous, and the average value of heart rate growth rate of the driver is 26.3%, and the average value of PSD integral value of EEG
$\alpha /\beta $
is 0.68, which is in the state of nervousness; under the conditions of different braking speeds, the heart rate growth rate of the driver is more than 27% of the nervousness threshold, and the ratio value of EEG
$\alpha /\beta $
wave is less than 1, which is the same as that of EEG
$\alpha /\beta $
wave. The ratio of EEG
$\alpha $
-wave to
$\beta $
-wave is lower than 1, and the degree of alertness is higher; under the condition of different road surface sand thickness, when the thickness of road surface sand is 0-2mm, the average value of the driver’s heart rate growth rate is the maximum of 26.2%, the braking distance is increased obviously, and the
$\alpha /\beta $
is reduced significantly, and the driver has a potential safety problem. The results of the study are of great significance to improve the safety of driving on desert highways and reduce the risk of accidents.