Study On The Psychological Characteristics Of Drivers And Vehicle State Based On The Highway Linear

Nowadays,the scale of the road traffic network in China is enlarged quickly,especially for mountainous expressways,but its accident rate increases substantially as wel.The bad roadway geometrical design is one of the contributing factors on the safety performance of mountainous expressways,which presents as steep grade,small curvature radius and signific a nt variations on the two aspects.Moreover,the countermeasures to avoid traffic crashes are rare.To improve the safety performance at the slope-curve sections on mountainous expressways,this thesis aims to learn the law of speed variation and the characteristics of drivers' physiolo gy and psychology.Based on the extant literature on physiology,psychology,ergonomics and transportatio n engineering and the assumption that road users,vehicles and roadways interact mutually,the thesis analyzes drivers' mental load and the stability of vehicle traveling under different roadway geometrical conditions,by using the indices on heart rate,speed,acceleration,etc.,which are able to reflect the characterstics of driver behavior and driving performance.Specifically,first,using the driver characteristic data collected by questionnaire,we mainly analyze drivers' subjective feeling and driving modes while driving on mountainous expressways,and their acceptance on the safety protection measures.The survey results show that,more than 83 % drivers think that long and steer slops and sharp turns are the most dangerous sections on mountainous expressways,probably resulting in emotional tension,thereby leading to wrong driving manoeuvre or misjudgement on the forward roadway situatio n.Over a half drivers prefer to drive on gentle and long slops,or reverse slope combinations.Most drivers believe that setting warning or information signs and strengthening traffic safety education would improve the safety performance significantly.Second,we select several typical slope-curve sections on mountainous expressways as the real vehicle experiment fields.The grade,length and curvature radius of these sites are measured.In the experiments,we record the speed and acceleration indices on vehicle control and the heart rate increase rate on drivers' physiological states.Then,we analyze the law of speed variation and the characteristics of drivers' physiology and psychology under different roadway geometrical conditions.Finally,we deeply analyze the indices,including LF/HF,mean heart rate,the standard deviation of speed,the mean and standard deviation of absolute acceleration,using the principa l component analysis method.To learn the relationship between the heart rate increase rate and drivers' mental load,we develop the model for heart rate increase rate under the multi regression framework.According to the results of the questionnaire survey and real vehicle experiments,we propose a number of suggestions on the traffic safety management of slope-curve sections on mountainous expressways,from the perspective of drivers' safety and comfort.